Amphineurus can be diagnosed by the following combination of characters: gonocoxite bifid; wing with R₂₊₃₊₄ aligned with R₂₊₃. When there is an element R₄₊₅ (and therefore, no R₂₊₃), members of the genus are distinguished from other Chioneinae by the closed discal cell.

There is great diversity in the male terminalia of Amphineurus (Figs 1, 2). There are many variations from the simplified pattern of A. (A.) patya Theischinger (Fig. 1A) to the asymmetric disposition of A. (Nesormosia) (Fig. 2D). Therefore, defining a broad diagnosis for Amphineurus is not so easy. Skuse (1890) defined Amphineurus as a subgenus of Rhypholophus. Skuse’s definition fits better to the current subgenus A. (Amphineurus) but does not portray the reality of other species of Amphineurus. His diagnosis included the absence of the discal cell, the radial sector with four branches, “second longitudinal vein angulated”, and hind femora one third longer than the intermediate pair. These features are non-exclusive or variable in the genus.

Alexander (1920) allocated Amphineurus as a subgenus of Ormosia after highlighting the abundant and conspicuous wing macrotrichia (Fig. 5B). Edwards (1923) redefined the genus to support two New Zealand species. Edwards’ diagnosis includes the short mid-leg, short and hairy wing, and radius four-branched. Nevertheless, these features occur in other Chioneinae. Edwards (1923) also referred to the fact that the medial vein forks in M₃₊₄ and M₁₊₂ and that the anal vein is sinuous. These features are plastic in the genus. Alexander (1929a) used the definition of Edwards (1923) and emphasized the characteristic “abundant trichiation” of the genus. However, in the same article, Alexander (1929a) described the genus Maietta, which has more wing vestiture than Amphineurus. Some species of the Neotropical subgenus A. (Rhamphoneurus) have less macrotrichia than other subgenera. No more inclusive diagnosis was proposed and recent revisions (e.g., Theischinger 1994, 1996) redefined only the diagnosis of the subgenus A. (Amphineurus).

Amphineurus has an 180º rotation of male terminalia (in the words of Edwards: “undergone permanent torsion”). Edwards (1923) also shows that Amphineurus has a long, finger-like gonocoxite process (Fig. 1A). This is evidence of the bifid gonocoxite, a condition present (Fig. 29G) in some Chioneinae with inverted male terminalia. This gonocoxal process forms a protective hood (Kramer 2020) for the appendices of the inverted terminalia.

The Chioneinae genera with inverted terminalia bear great diversity and frequently they have hairy wings similar to Amphineurus. The great amount of wing vestiture resembles Maietta Alexander. The wings of some A. (Amphineurus) (Fig. 32: Node 18) have a distinctive radial sector such as seen in Molophilus Curtis. Some A. (Amphineurus) (Fig. 32: Node 23) resembles Hoplolabis (Parilisia Savchenko). The trifid claspers of A. (Rhamphoneurus) are observed in genera such as Hoplolabis Osten Sacken and Cheilotrichia Rossi. Despite that, in the group of genera with a bifid gonocoxite and inverted terminalia, vein R₂₊₃ is normally aligned with R₂₊₃₊₄. The exception is a clade of A. (Amphineurus) (Fig. 32: Node 18) that shows resemblances in the radial sector with Molophilus (where R₂₊₃₊₄ is lacking), but the former has a closed discal cell among other wing features which places it within Amphineurus.

This subgenus is distinguished by the rostrum at least as long as the remainder of the head. Cell M₂ open.

Habitus of representative species of the subgenus A. (Rhamphoneurus) is shown in Fig. 3. Head as long as wide in lateral view (Fig. 4A). Two ventral cervical sclerites of same proportions, longer than wide, while sclerite in middle of neck nearly horizontal; sclerite near head more vertically orientated (Fig. 4A). Neck approximately 2.5× shorter than head. Rostrum as long as remainder of head. In some specimens, dorsal concentration of setae at end of rostrum. End of rostrum with sclerotized bifurcated tips (Fig. 4B) of variable sizes and shapes. Antenna 16-segmented, ca. twice length of head. Scape cylindrical, 2× longer than wide. Pedicel rounded, as long as wide. Pedicel approximately as long as scape. First flagellomere ca. 1.2× longer than pedicel. Pedicel ca. 1.5× wider than first flagellomere. Flagellomeres ca. 2× longer than wide. Flagellomeres vary in pilosity. Terminal flagellomere may be expanded. Palpus with 4 segments and large auxiliary segment at base (Fig. 4A). Palpus ca. 1.4× longer than rostrum. Length of palpal segments variable, but all cylindrical and similar in width. Wings 3–3.5× longer than wide, bearing typical distinctive hairs. Wing veins run mostly in parallel (Fig. 5), especially in radial sector. Vein Sc complete. Crossvein sc-r near origin of Rs. R₂ complete or faded. Tip of R₁ complete or faded. Insertion of m-cu variable: proximal to fork of bM, in fork of bM, or M₃₊₄. Discal cell open. Wing markings in shades of brown important taxonomically. Thorax ca. 1.5× longer than wide in lateral view. Tibial spurs absent. Empodium pulviliform. Two tarsal claws present. Abdomen ca. 2× longer than thorax, 3× longer than head. Male terminalia inverted. Male terminalia with posterior margin of tergite IX usually with median notch (Fig. 23G); posterior margin may bear medial sclerotized projection (Fig. 28G); darkened in most species (Fig. 20F). Gonocoxite bifid (Fig. 6) with long ventral branch and short dorsal branch; additional branch of gonocoxite (= mesal lobe) present in majority of species (Fig. 6), very variable, including asymmetry. If asymmetrical, right and left mesal lobes drawn in corresponding position on plates. Gonostylus bifid (Fig. 6) with medial and lateral branches. Clasper of gonostylus very variable. Lobe of gonostylus ca. as long as clasper. Lobe of gonostylus bifid, smaller pigmented branch termed lobule (Fig. 6). Sheath of aedeagus variable, as in other Chioneinae, projecting ventrally to aedeagus and almost detached form aedeagus. Female terminalia with curved cercus. Hypogynial valve blade-shaped, variable in length. Genital fork (Fig. 7B) without membranous area, posterior region concave similar to other Chioneinae such as Erioptera Meigen. Two oval-shaped spermathecae present, longer than wide (Fig. 7A).

Holotype: ♂, Chile, Llanquihue, Carelmapu [41°44′S 73°40′W], Coast of Canal de Chacao, 18-III-1957, Peña (USNM)*. Paratypes: 1 ♂, Chile, Chiloé Is., Dalcahue [42°22′S 73°39′W], 10/12-II-1954, Peña (USNM)*; 1 ♂, Chile, Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, Peña (USNM)*.

The species is named after C.P. Alexander, the remarkable Tipulomorpha expert who described all the species of this subgenus, among many others.

This species is distinguished by a curved R₂₊₃, large markings only near R₂, r-m longer than basal deflection of R₅, and R₂₊₃₊₄ longer than R₂₊₃. Furthermore, the species has characteristic male terminalia with a trapezoidal-shaped spur and symmetrical tip of left mesal lobe.

Wing length 5.68 mm, width 1.61 mm. — Coloration: General coloration dark brown. Rostrum and palpus dark brown. First segment of antenna yellowish-brown, remaining segments dark brown. Head dark brown. Abdomen brown. — Head (dorsal view Fig. 8B, ventral view Fig. 8A): terminal segments of antenna missing, as indicated by asterisks on Fig. 8B. Rostrum bifurcated with short appendices; first palpal segment shorter than terminal segment; scape shorter and thinner than pedicel. Thorax: Wing (Fig. 8C) almost clear of markings, except strong marking covering R₂; veins near fork of bM (Fig. 8D) faded; r-m similar in length to basal deflection of R₅; M₁₊₂ shorter than basal deflection of M₁; R₂₊₃₊₄ longer than R₂₊₃, more than twice length of R₅. — Male terminalia (Fig. 8E): Male tergite IX slightly darkened at posterior margin, with wide V-shaped median notch; posterolateral lobes triangular. Ventral branch of gonocoxite with one side with a few long setae, while other side with many short setae. Dorsal branch of gonocoxite half-length of ventral branch. Lobe of gonostylus with rounded lobule; lobule longer than wide, longer than half length of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch wide club-shaped. Mesal lobes of gonocoxite asymmetrical; left mesal lobe with flat posterior margin; right mesal lobe elongated and curved. Sheath of aedeagus straight, darkened halfway of length; apex extended into narrowed tip and additional nearly rectangular preapical spur.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) insanus Alexander. This species resembles A. (R.) insanus but differs mainly in the attachment of m-cu, length of r-m, shape of thorax, mesal lobe and sheath of aedeagus.

Holotype: ♂, Chile, Chiloé Is., Dalcahue [42°22′S 73°39′W], 10/12-II-1954, Peña (USNM)*. Paratypes: 2 ♂, Chile, Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM)*; 1 ♂, Chile, Caramavida [37°40′S 73°20′W], 1000–1300 m, 1-I-1954, Peña (USNM)*. — Additional material: CHILE. 3 [sex unknown], Chiloé Is., Dalcahue [42°22′S 73°39′W], 10/12-II-1954, Peña (USNM); 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM).

The species is named after Dalton de Souza Amorim, a remarkable Brazilian Diptera expert.

This species is distinguished by only a marking near R₂ and R₂₊₃₊₄ as long as R₂₊₃. Furthermore, the species has characteristic male terminalia with a triangular spur and an atrophied tip of the left mesal lobe.

Wing length 5.60 mm, width 1.68 mm. — Coloration: General coloration dark brown. Thorax dark brown, pleura brown. Scutum without stripes. Halter dark brown with knob pale. Coxae light brown and legs brown. — Head (dorsal view Fig. 9B, ventral view Fig. 9A): Rostrum bifurcated with long appendices; first palpal segment shorter than terminal segment; scape thinner than pedicel, terminal flagellomere longer than penultimate. — Thorax (lateral view Fig. 9E, dorsal view Fig. 9F): Thorax with long setae, notably on coxae. Anatergite taller than katatergite. Halter with dilated knob. Wing (Fig. 9D) almost clear of markings, except for strong marking covering R₂; veins near fork of bM (Fig. 9C) faded; M₁₊₂ shorter than basal deflection of M₁, R₂₊₃₊₄ similar in length to R₂₊₃. — Male terminalia (Fig. 9G): Male tergite IX slightly darkened at posterior margin, with wide V-shaped median notch; posterolateral lobes nearly triangular. Ventral branch of gonocoxite slender. Dorsal branch of gonocoxite shorter than half length of ventral branch, setose on distal tip. Lobe of gonostylus with rounded lobule; lobule longer than wide, longer than half-length of lobe of gonostlyus, about as wide as stem. Clasper of gonostylus with differently shaped branches: lateral branch long and straight; medial branch curved, club-shaped. Mesal lobes of gonocoxite asymmetrical; left mesal lobe straight and narrow, with small bend at distal section; right mesal lobe curved, elongated. Sheath of aedeagus straight; apical half darkened, with short, curved triangular projection.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) insanus Alexander. This species resembles A. (R.) morphyi sp. nov. but differs mainly in the chaetotaxy of the thorax and gonocoxite, length of R₂₊₃₊₄ and shape of the mesal lobe.

Holotype: ♂, Chile, Arauco, Nahuelbuta, Contulmo, Palo Botado [37°39′S 72°54′W], 12-II-1952, Peña (USNM)*. Paratypes: 1 ♂ and 1 [sex unknown], Chile, Arauco, Nahuelbuta [37°46′S 72°59′W], 2-II-1953, Peña (USNM); 1 [sex unknown], Chile, Chiloé Is., Rio Coluco [42°6′S 73°55′W], 30-I-1952, Peña (USNM).

The word anchoralis is Latin for “of the anchor”. The term refers to the shape of the projection of the male 9th tergite, which resembles an anchor.

The species is distinguished by the absence of markings near R₁, and R₂₊₃ shorter than R₂. Furthermore, this species has a long vertical spur on the sheath of aedeagus, male tergite IX has a distinctive ridge projection, mesal lobes absent and the posterior margin of the male tergite IX is mostly unpigmented.

Wing length 6.15 mm, width 1.86 mm. — Coloration: General coloration yellowish brown. Rostrum and palpus dark brown. First segments of antenna pale, remaining segments dark yellow. Head brownish-black. Eyes black. Thorax yellowish-brown, pleura pale. Scutum without stripes. Halter pale with knobs light orange. Coxae and legs brownish. — Head (dorsal view Fig. 10B, ventral view Fig. 10A): Rostrum bifurcated with short appendices; first palpal segment as long as terminal segment, second palpal segment dilated; scape thinner than pedicel, terminal flagellomere dilated, antenna with several long setae. — Thorax (lateral view Fig. 10E, dorsal view Fig. 10F): a few setae on prescutum. Division line of laterotergite almost vertical; anatergite as tall as katatergite. Halter with dilated knob. Wing (Fig. 10D) almost clear of markings, except marking covering R₂; veins near fork of bM (Fig. 10C) faded; M₁₊₂ longer than basal deflection of M₁; R₂₊₃₊₄ at least twice as long as R₂₊₃. — Male terminalia (Fig. 10G): Male tergite IX with posterior margin with irregular ridges; median U-shaped notch with straight projection in middle; tip of projection also ridge shaped; projection and surrounding area darkened. Ventral branch of gonocoxite inclined laterally. Dorsal branch of gonocoxite half-length of ventral branch, atrophied and pointed medially; both branches setose. Lobe of gonostylus with pointed lobule, shaped similar to folded leaf. Clasper of gonostylus with differently shaped branches: lateral branch long, bent near middle; medial branch curved into stub. Mesal lobes absent. Sheath of aedeagus darkened on apical half, angulated, with long pointed projection perpendicular to remainder of sheath.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) sanus Alexander and A. (R.) insanus Alexander. This species resembles A. (R.) sanus but differs mainly in M₁₊₂, shape of projection in male tergite IX, ventral branch of gonocoxite and spur of sheath of aedeagus.

Holotype: ♂, Chile, Arauco, Nahuelbuta, Butamalal [37°49′S 73°14′W], 1100–1400 m, 23/31-I-1954, Peña (USNM)*. Paratypes: 1 [sex unknown], Chile, Arauco, Nahuelbuta [37°46′S 72°59′W], 5/10-II-1953, Peña (USNM); 1 ♂, Chile, Arauco, Nahuelbuta, Butamalal [37°49′S 73°14′W], 1100–1400 m, 23/31-I-1954, Peña (USNM)*.

The word anfractus in Latin is for “winding”. The term refers to the winding or sinuous aspect of the anal vein and crossvein m-cu.

This species is distinguished by sinuose crossvein m-cu and anal vein. Furthermore, this species is characterized by the male terminalia with a folded medial branch of the clasper of gonostylus and a cylindrical left mesal lobe.

Wing length 7.84 mm, width 2.48 mm. — Coloration: General coloration dark brown. Thorax dark brown, pleura brown. Scutum with one black stripe. Halter pale with knobs ochreous. Coxae brownish yellow and legs dark brown. — Head (dorsal view Fig. 11B, ventral view Fig. 11A): Rostrum bifurcated with long appendices; first palpal segment shorter than terminal segment; scape as thick as pedicel, pedicel constricted at base; terminal flagellomere shorter than penultimate, antenna with long setae. — Thorax (lateral view Fig. 11E, dorsal view Fig. 11F). Division line of laterotergite very sinuous; anatergite shorter than katatergite. Halter with dilated knob. Wing (Fig. 11D) with several marks, including faint markings on A₁ and near tip of R₃, marking highlighting m-cu, markings on Rs, R₂₊₃₊₄ and R₂₊₃, small, strong marking at tip of R₁ and large, strong marking covering R₂; veins near fork of bM (Fig. 11C) faded; A₁ sinuose; M₁₊₂ longer than basal deflection of M₁; R₂₊₃₊₄ longer than R₂₊₃. — Male terminalia (Fig. 11G): Male tergite IX darkened along posterior margin; posterior margin flat, with short median U-shaped notch; posterolateral lobes nearly rectangular with slightly visible shallow emarginations. Ventral branch of gonocoxite wide. Dorsal branch of gonocoxite long, almost as long as ventral branch, with long setae on distal tip. Lobe of gonostylus with rounded lobule; lobule wider than long, shorter than half-length of lobe of gonostylus, twice as wide as stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch curved, club-shaped. Mesal lobes of gonocoxite asymmetrical, both similarly shaped with flat posterior margins; left mesal lobe narrower. Sheath of aedeagus slightly curved on distal half, with tip narrowed, darkened almost along entire length.

Some specimens of this new species were previously identified by C.P. Alexander as A. (R.) glabristylatus Alexander and some as A. (R.) nothofagetorum Alexander. This species resembles A. (R.) chiloeanus but differs mainly in the form of the anal vein, shape of male tergite IX, sheath of aedeagus and mesal lobe.

Holotype: ♂, Chile, Chaihuin [39°56′S 73°34′W], 810 m, 20-III-1955, Peña, Holotype 12206 (USNM) [part of specimen pinned and part on slide prepared by C.P. Alexander].

This species is distinguished by having vein bM forking into M₂₊₃₊₄ and M₁, absence of markings on R₂ and insertion of r-m desclerotized. Furthermore, the species has distinctive male terminalia with a curved sheath of aedeagus and both mesal lobes similar in length with vertically directed tiny tips.

Wing length 6.26 mm, width 1.82 mm. — Coloration: General coloration yellowish brown. Rostrum and palpus brown. First segment of antenna yellow, remainder segments brown. Head brownish gray. Eyes black. Thorax yellowish-brown, pleura brown. Scutum without stripes. Halter yellow. Coxae light yellow and legs dark yellow. Abdomen yellowish-brown. — Head (Fig. 12A): Rostrum bifurcated with short appendices; first palpal segment shorter than terminal segment; scape as thick as pedicel; terminal flagellomere longer than penultimate. — Thorax (lateral view Fig. 12D, dorsal view Fig. 12E): Thorax with several long setae. Anatergite shorter than katatergite. Halter with very dilated knob. Wing (Fig. 12C) without distinct markings; veins near fork of bM (Fig. 12B); R₂ partially faded; bM forking into M₁ and M₂₊₃₊₄; R₂₊₃ longer than R₂₊₃₊₄. — Male terminalia (Fig. 12F): Male tergite IX darkened on posterior margin, with wide V-shaped median notch; posterolateral lobes obtuse. Ventral branch of gonocoxite wide. Dorsal branch of gonocoxite half-length of ventral branch. Lobe of gonostylus with rounded lobule; lobule longer than wide, longer than half length of lobe of gonostylus, wider than stem. Clasper of gonostylus with similarly shaped branches: lateral branch rounded; medial branch curved. Mesal lobes of gonocoxite asymmetrical both similarly shaped, with pointed tip; right mesal lobe longer and narrower. Sheath of aedeagus elongated, curved, darkened only at tip.

This species resembles A. (R.) nonnullus Alexander but differs mainly in the fork of bM, shape of male tergite IX, clasper of gonostylus and mesal lobe.

Holotype: ♂, Chile, Osorno, Pucotrihue [40°32′S 73°42′W], 10/12-IV-1968, Peña (USNM)*. Paratype: 1 [sex unknown], Chile, Chiloé Is., Chepu [42°2′S 74°1′W], 14-II-1952, Peña (USNM).

The species is named after Zacariah D. Billingham, a great expert of Australian craneflies.

This species is characterized by crossvein m-cu uniformly inserted at the fork of bM. Furthermore, this species is characteristized by the male terminalia with a curved sheath of aedeagus, a small right mesal lobe and the most setose ventral branch of gonocoxite. The thorax is also distinguishable by a narrow knob of the halter and katepisternum longer than the meron.

Wing length 6.45 mm, width 1.66 mm. — Coloration: General coloration dark brown. Rostrum and palpus dark brown. First segments of the antenna yellow, remainder dark yellow. Head dark brown. Eyes blackish gray. Thorax dark brown, pleura pale. Scutum without stripes. Halter pale with knob dark yellow. Coxae brownish yellow and legs yellowish-brown. — Head (dorsal view Fig. 13B, ventral view Fig. 13A): Rostrum bifurcated with short appendices; first palpal segment as long as terminal segment; scape thicker than pedicel, terminal flagellomere as long as penultimate. — Thorax (lateral view Fig. 13E, dorsal view Fig. 13F): Thorax with long setae, particularly on scutum. Anatergite as tall as katatergite. Halter with narrow knob. Wing (Fig. 13D) without clear markings; veins near fork of bM (Fig. 13C) visible; m-cu inserted at fork of bM; M₁₊₂ longer than basal deflection of M₁; R₂ faded; R₂₊₃₊₄ shorter than R₂₊₃. — Male terminalia (Fig. 13G): Male tergite IX with small V-shaped median notch; posterolateral lobes rounded. Ventral branch of gonocoxite expanded on distal tip. Dorsal branch of gonocoxite nearly half-length of ventral branch; both branches extremely setose. Lobe of gonostylus rounded, longer than wide; longer than half-length of lobe of gonostylus; lobule wider than stem. Clasper of gonostylus with similarly shaped branches; lateral branch rounded; medial branch oblong. Mesal lobes of gonocoxite asymmetrical, both pointed, with several setae on posterior margin; right mesal lobe shorter. Sheath of aedeagus claw-shaped, curved halfway, darkened only on tip.

Remarks. Specimens of this new species were previously identified by C.P. Alexander as A. (R.) nullus Alexander. This species resembles A. (R.) theischingeri sp. nov. but differs mainly in attachment of m-cu, setae concentration in gonocoxite, shape of male tergite IX, and mesal lobe.

Holotype: ♂, Chile, Chiloé Is. Ancud [41°52′S 73°48′W], 23-I-1932, Peña (USNM)*. Paratypes: 1 ♀, Chile, Chiloé Is., Aucar [42°9′S 73°30′W], 6/15-I-1952, Peña (USNM); 2 ♂, Chile, Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM)*. Additional material: CHILE. 1 [sex unknown], Chiloé Is., Aucar [42°9′S 73°30′W], 6/15-I-1952, Peña (USNM); 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5-II-1954, Peña (USNM); 1 ♂, Chiloé Is. Ancud [41°52′S 73°48′W], 18/19-XII-1926, F. & M. Edwards (USNM)*; 1 ♂, Chiloé Is., Aucar [42°9′S 73°30′W], 6/15-I-1952, Peña (USNM)*; 1 ♂, Arauco, Nahuelbuta [37°46′S 72°59′W], 5/10-II-1953, Peña (USNM) [slide mounted specimen prepared by the authors].

The word caleuchus refers to the Chilean myth of Caleuche, a sentient ghost ship of the Chiloé islands (Febles 2009). The species is named after this myth due to holotype and the majority of specimens being from the Chiloé islands.

The species is distinguished by a darkened distal quarter of the wing, R₂₊₃₊₄ similar to R₂₊₃, and M₁₊₂ shorter than the basal deflection of M₁. Furthermore, the species is characterized by the distinctive clasper of gonostylus with setae on medial branch, curved lateral branch and male tergite IX with a very shallow notch.

Wing length 6.50 mm, width 2.05 mm. — Coloration: General coloration dark brown. Rostrum and palpus dark brown. First segments of antenna yellow, remainding segments brownish-yellow. Head brown. Eyes black. Thorax yellowish-brown, pleura yellowish brown. Scutum with three dark brown stripes. Halter pale with knob ochreous. Coxae yellow and legs brown. Abdomen dark brown. — Head (dorsal view Fig. 14B, ventral view Fig. 14A): Rostrum bifurcated with short appendices; first palpal segment shorter than terminal segment; scape as thick as pedicel; terminal flagellomere as long as penultimate; antenna with long setae. — Thorax (lateral view Fig. 14E, dorsal view Fig. 14F): Thorax with short setae, some organized in rows on prescutum. Division line of laterotergite almost vertical; anatergite shorter than katatergite. Halter with dilated knob. Wing (Fig. 14D) almost clear of markings, except for faint markings on R₂ and tip of R₁; distal quarter of wing darkened; veins near fork of bM (Fig. 14C) faded; M₁₊₂ shorter than basal deflection of M₁; R₂₊₃₊₄ as long as R₂₊₃. — Female terminalia (Fig. 14H): Female tergite IX longer and narrower than tergite X; cercus thin and bent at right angle. — Male terminalia (Fig. 14G): Male tergite IX with sinuose posterior margin. Ventral branch of gonocoxite slightly inclined laterally, with long setae on lateral margin. Dorsal branch of gonocoxite reduced. Lobe of gonostylus with rounded lobule; lobule longer than wide, shorter than half-length of lobe of gonostylus, and narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch straightened, slightly bent towards tip; medial branch curved, club-shaped with concentration of setae. Mesal lobes symmetrical, rounded at posterior margin with bump on side. Sheath of aedeagus angulated with two bends; darkened almost along entire length.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) nothofagetorum Alexander. This species resembles A. (R.) stigmaticus sp. nov. but differs mainly in markings on the sheath of aedeagus, length of R₂₊₃₊₄, and shape of lobe of gonostylus, cercus and mediotergite.

Holotype: ♂, Chile, Chiloé Is., Dalcahue [42°22′S 73°39′W], 1/4-IV-1954, Peña, Holotype 12553 (USNM) [part of specimen pinned and part in slide prepared by C.P. Alexander]. Paratype: 1 ♂, Chile, Chiloé Is., Dalcahue [42°22′S 73°39′W], 1/4-IV-1954, Peña (USNM). Additional material: CHILE. 1 [sex unknown], Chile, Chiloé Is. Ancud [41°52′S 73°48′W], 23-1-1952, L. Guzman (USNM); 1 ♂, Chiloé Is., Dalcahue [42°22′S 73°39′W], 1/4-IV-1954, Peña (USNM)*.

The species is distinguished by having m-cu strongly sinuous, straight anal vein and beginning of M₁₊₂ retains sclerotized section. Furthermore, this species has a characteristic sheath of aedeagus with a long basal spur, mesal lobe is very reduced and male tergite IX is remarkable by its rounded posterolateral lobes.

Wing length 7.37 mm, width 2.14 mm. — Coloration: General coloration light brown. Rostrum and palpus dark brown. First segment of antenna light yellow, remaining segments dark yellow. Head dark brown. Eyes black. Thorax light brown, pleura dark yellow. Scutum with three brown stripes. Halter brownish yellow with knob ochreous. Coxae brownish yellow and legs yellowish-brown. — Head (dorsal view Fig. 15B, ventral view 15A): terminal segments of antennae missing, as indicated by asterisks. Rostrum bifurcated with short appendices; first palpal segment longer than terminal segment; scape as thick as pedicel, pedicel constricted at base. — Thorax (lateral view Fig. 15E, dorsal view Fig. 15F): Division line of laterotergite very sinuous; Anatergite shorter than katatergite. Halter with dilated knob. Wing (Fig. 15D) with some markings, including faint markings on A₁ and Rs; markings highlighting m-cu, r-m, fork of Rs and R₂₊₃₊₄; distal quarter of wing slightly darkened, with large, strong marking covering R₂ and last segment of R₁; veins near fork of bM (Fig. 15C) faded; R₂₊₃₊₄ longer than R₂₊₃. — Male terminalia (Fig. 15G): Male tergite IX faintly darkened at posterior margin, with wide, shallow U-shaped median notch; posterolateral lobes rounded. Dorsal branch of gonocoxite poorly developed, shorter than half-length of ventral branch. Lobe of gonostylus with elongate lobule, longer than wide, longer than half-length of lobe of gonostylus, but narrower than stem. Clasper with differently shaped branches: lateral branch straight and long; medial branch curved, wide club-shaped. Mesal lobes atrophied, similar in shape to dorsal branch of gonocoxite. Sheath of aedeagus long and sinuose, darkened almost entire length, with pointed perpendicular spur projecting at end of straight section.

Some specimens of this species were misidentified by C.P. Alexander as A. (R.) nothofagetorum Alexander. This species resembles A. (R.) glabristylatus Alexander but differs mainly in attachment of m-cu, length of cercus, shape of male tergite IX, sheath of aedeagus and mesal lobe.

The species Amphineurus extraordinarius was originally included in the subgenus Amphineurus. In all the phylogenetic analysis we performed (see below in this paper), this species is the sister-group of the other species of Rhamphoneurus, and we think it should be transferred to this subgenus. This new subgenus placement is therefore based on the phylogenetic analysis, but specimens of A. extraordinarius were not available when the analysis was finalized. Consequently, a redescription of the species is not possible at this time.

Holotype: ♂, Chile, Chiloé Is. Ancud [41°52′S 73°48′W], 23-I-1952, Peña (USNM)*. Paratypes: 1 ♂, Chile, Arauco, Nahuelbuta, Butamalal [37°49′S 73°14′W], 1100–1400 m, 23/31-I-1954, Peña (USNM); 1 ♀, Chile, Chiloé Is., Castro [42°28′S 73°46′W], 20/22-XII-1926, R.C. Shannon (USNM); 1 ♂, Chile, Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM)*. — Additional material: CHILE. 1 [sex unknown], Chiloé Is. Ancud [41°52′S 73°48′W], 23-I-1952, L.P. Guzman (USNM); 1 [sex unknown], Llanquihue, Hornohuinca [41°25′S 72°37′W], XII-1968, Peña (USNM); 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM); 1 [sex unknown], Chiloé Is., Aulen [42°2′S 74°1′W], 4-II-1952, Peña (USNM)*;

The word deceptus is Latin for “deceived”. The term refers to the fact that specimens of this new species were misidentified by Alexander as two different species.

This species is distinguished by the darkened distal quarter of the wing, and bM is uniform. Furthermore, the species is characterized by the distinctive male terminalia with clasper of gonostylus with setae on medial branch and straightened base of sheath of aedeagus.

Wing length 6.50 mm, width 2.06 mm. — Coloration: General coloration dark brown. Rostrum and palpus brownish-black. First segments of the antenna yellow, remainding segments dark yellow. Head dark brown. Eyes gray. Thorax dark brown, pleura yellowish brown. Scutum with three dark brown stripes. Halter brownish-yellow. Coxae brownish yellow and legs yellowish-brown. Abdomen dark brown. — Head (dorsal view Fig. 16B, ventral view Fig. 16A): Rostrum bifurcated with long appendices; first palpal segment shorter than terminal segment; scape as thick as pedicel; terminal flagellomere as long as penultimate; antenna with long setae. — Thorax (lateral view Fig. 16E, dorsal view Fig. 16F): Prescutum with short setae. Division line of laterotergite almost vertical; anatergite as tall as katatergite. Halter with dilated knob. Wing (Fig. 16D) with several markings, including faint markings on A₁ and Rs, marking at tip of R₁, markings highlighting m-cu, R₂₊₃₊₄ and R₂₊₃, and strong marking covering R₂; distal quarter of wing darkened, veins near fork of bM (Fig. 16C) faded; M₁₊₂ shorter than basal deflection of M₁; R₂₊₃₊₄ shorter than half-length of R₂₊₃. — Female terminalia (Fig. 16H): Female tergite IX longer and as wide as tergite X; cercus slightly curved dorsad. — Male terminalia (Fig. 16G): Male tergite IX with V-shaped median notch. Ventral branch of gonocoxite with long setae on lateral margin. Dorsal branch of gonocoxite half-length of ventral branch. Lobe of gonostylus with rounded lobule; lobule longer than wide, shorter than half-length of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch long and straight, bent near tip; medial branch curved, club-shaped. Mesal lobes of gonocoxite asymmetrical; left mesal lobe with more rectangular posterior projection; right mesal lobe rounded with bump on side. Sheath of aedeagus straightened, bent towards tip, darkened almost along entire length.

Some specimens of this new species were previously identified by C.P. Alexander as A. (R.) glabristylatus Alexander and some as A. (R.) nothofagetorum Alexander. This species resembles A. (R.) nothofagetorum but differs mainly in the shape of the branches of the clasper, male tergite IX, mesal lobes and sheath of aedeagus.

Holotype: ♂, Chile, Osorno, Bahia Mansa [40°35′S 73°44′W], South of Pucotrihue, 12-IV-1968, Peña (USNM)*. Paratypes: 1 [sex unkown]: Chile, Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, L.P. Guzman (USNM); 1 ♂, Chile, Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, Peña (USNM)*; 1 [sex unkown]: Chile, Chiloé Is., Aulen, Duhatao [41°58′S 74°02′W], 6/8-II-1952, Peña (USNM)*.

The word falcatus is Latin for “armed with scythes”. This name is in reference to the sheath of aedeagus, which resembles a scythe.

This species is distinguished by absence of markings near R₂ and R₂₊₃₊₄ longer than R₂₊₃. Furthermore, this species has distinctive male terminalia with a curved sheath of aedeagus, only the right mesal lobe folded, and the longest lobule of the subgenus, as long as the remainder of the lobe of gonostylus.

Wing length 6.08 mm, width 1.86 mm. — Coloration: General coloration blackish brown. Thorax blackish brown, pleura gray. Scutum without stripes. Halter ochreous. Coxae brownish yellow and legs dark brown. — Head (dorsal view Fig. 17B, ventral view Fig. 17A): Rostrum bifurcated with short appendices; first palpal segment as long as terminal segment; scape as thick as pedicel; last flagellomere as long as penultimate. — Thorax (lateral view Fig. 17E, dorsal view Fig. 17F): Division line of laterotergite sinuous and almost vertical; anatergite as tall as katatergite. Halter with long dilated knob; length of knob half-length of stem of halter. Wing (Fig. 17D) without distinctive markings; veins near fork of bM (Fig. 17C) visible; R₂ faded; r-m shorter than M₁₊₂ and basal deflection of M₁; M₁₊₂ shorter than basal deflection of M₁; R₂₊₃ at least 2.5× longer than basal deflection of R₅; R₂₊₃₊₄ longer than R₂₊₃. — Male terminalia (Fig. 17G): Male tergite IX darkened along posterior margin, with wide V-shaped median notch; posterolateral lobes nearly triangular, obtuse at apex. Ventral branch of gonocoxite expanded on distal tip. Dorsal branch of gonocoxite shorter than half-length of ventral branch. Lobe of gonostylus with rounded lobule; lobule longer than wide, longer than half-length of lobe of gonostylus and wider than stem. Clasper of gonostylus with similarly shaped branches: lateral branch rounded; medial branch oblong. Mesal lobes of gonocoxite asymmetrical; left mesal lobe straightened and pointed; right mesal lobe bent at right angle. Sheath of aedeagus curved, darkened for most of length.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) nullus Alexander. This species resembles A. (R.) nullus but differs mainly in the attachment of m-cu, shape of male tergite IX, prescutum and left mesal lobe.

Amphineurus (R.) fuscifusus Alexander is the only species of the genus in which the male is unknown. Additionally, the only identified specimen is the female holotype, currently housed in the Natural History Museum (BMNH). The absence of an associated male specimen and its terminalia is problematic because this is an important source of characters and taxonomic data. Lacking a well-defined diagnosis in the description, the erection of the new species was proposed mostly due to subtle differences in coloration. The only considerable difference in coloration in A. (R.) fuscifusus is the pale halter, which is unlike the yellowish brown halter of A. (R.) nothofagetorum Alexander.

Some morphological data described by Alexander (1929a) suggest this specimen shares similar features with clade 33 (Fig. 32). The presence of long setae on the antenna, “weak branches” in medial veins, three stripes on the scutum, and a marking near the fork of Rs are features shared between the holotype and this group. The holotype was collected in the same location as the holotype of A. (R.) nothofagetorum Alexander. However, the absence of males added to the fact that there is only a single known specimen makes the synonymization or identity confirmation of the species problematic. For these reasons, we define Amphineurus (Rhamphoneurus) fuscifusus Alexander as nomen dubium.

Paratypes: 1 ♂, Chile, Chiloé Is., Mechuque Is. [42°18′S 73°16′W], 23-XII-1926, F. & M. Edwards (USNM). 1 ♂, Chile, Peulla [41°5′S 72°1′W], 12/13-XII-1926, F. & M. Edwards (USNM); 1 ♂, Chile, Chiloé Is., Mechuque Is. [42°18′S 73°16′W], 23/26-XII-1926, F. & M. Edwards (USNM)*. — Additional material: ARGENTINA. 1 ♀, Bariloche, Rio Negro [41°7′S 71°24′W], XI-1926, R. & E. Shannon (USNM). CHILE. 1 ♂, 1 ♀ and 4 [sex unknown], Arauco, Nahuelbuta, Butamalal [37°49′S 73°14′W], 1100–1400 m, 23/31-I-1954, Peña (USNM); 2 ♀ and 1 ♂, Arauco, Nahuelbuta [37°46′S 72°59′W], 2-II-1953, Peña (USNM); 1 ♀ and 1 [sex unknown], Arauco, Nahuelbuta [37°46′S 72°59′W], 12/20-II-1958, Peña (USNM); 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 4/6-IV-1968, Peña (USNM); 1 [sex unknown], Arauco, Nahuelbuta, Butamalal [37°49′S 73°14′W], 1400 m, 23/31-I-1954, Peña (USNM); 1 ♀ and 1 [sex unknown], Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, L.P. Guzman (USNM); 1 [sex unknown], Arauco, Nahuelbuta [37°46′S 72°59′W], 21/25-II-1958, Peña (USNM); 1 [sex unknown], Malleco, Rio Blanco [38°23′S 71°48′W], 27-II-1951, Peña (USNM); 1 [sex unknown], Arauco, Nahuelbuta [37°46′S 72°59′W], 120-1100m., 9-I-1954, Peña (USNM); 1 ♀, Chiloé Is., Aucar [42°9′S 73°30′W], 15-I-1952, L. P. Guzman (USNM); 1 [sex unknown], Osorno, Pucotrihue [40°32′S 73°42′W], 10/12-IV-1948, Peña (USNM); 2 ♂ and 1 [sex unknown], Arauco, Nahuelbuta, Pichinahuel [37°48′S 73°02′W], 1400–1600 m, 21/25-II-1953, Peña (USNM)*; 2 ♂, Arauco, Nahuelbuta, Butamalal [37°49′S 73°14′W], 1100–1400 m, 23/31-I-1954, Peña (USNM)*; 1 ♂, Nahuelbuta, Caramavida [37°40′S 73°20′W], 120–1100 m, 9-I-1954, Peña (USNM) (det. as A. (R.) nothofagetorum by Alexander)*; 1 ♂, Arauco, Nahuelbuta, Butamalal [37°49′S 73°14′W], 1400 m, 23/31-I-1954, Peña (USNM)*; 1 ♂, Arauco, Nahuelbuta, Pichinahuel [37°48′S 73°02′W], 14–1600 m, 12/20-II-1953, Peña (USNM)*; 1 ♂, Chiloé Is., Aulen [42°2′S 74°1′W], 4-II-1952, Peña (USNM)*; 1 ♂, Osorno, Pucotrihue [40°32′S 73°42′W], 10/12-IV-1968, Peña (USNM)*; 1 ♂, Malleco, Rio Blanco [38°23′S 71°48′W], 1050 m, 27-III-1951, Peña (USNM)*.

This species is distinguished by the sinuous anal vein and straight m-cu. Furthermore, this species has characteristic male terminalia with a folded medial branch of the clasper of gonostylus without setae, an unpigmented male tergite IX, sinuous sheath of aedeagus, and the right mesal lobe is longer than the left mesal lobe, with a cylindrical apical tip.

Wing length 7.07 mm, width 2.22 mm. — Coloration: General coloration brown. Rostrum and palpus dark brown. First segments of antenna light yellow, remainding segments dark yellow. Head dark brown. Eyes gray. Thorax brown, pleura yellowish brown. Three reddish-brown stripes on scutum. Halter dark yellow with knob ochreous. Coxae yellowish-brown and legs brown. Abdomen brown. — Head (ventral view Fig. 18A, dorsal view Fig. 18B): Rostrum bifurcated with long appendices; first palpal segment shorter than terminal segment; scape as broad as pedicel, terminal flagellomere as long as penultimate; antenna with several long setae. — Thorax (lateral view Fig. 18E, dorsal view Fig. 18F). Anatergite taller than katatergite; prescutum with long setae (Fig. 29B); mediotergite with notch on posterior margin (Fig. 18F). Halter with dilated knob. Wing (Fig. 18D) with several markings, including subtle marking on A₁; slightly darkened areas along medial veins; markings on Rs, R₂₊₃₊₄ and m-cu; strong markings on R₂ and near end of R₁; veins near fork of bM (Fig. 18C) faded; M₁₊₂ longer than basal deflection of M₁, R₂₊₃ longer than R₂₊₃₊₄. — Female terminalia (Fig. 18H): Female tergite IX shorter, narrower than tergite X. Hypogynial valves slender, longer than cercus. Cercus strongly curved dorsad. — Male terminalia (Fig. 18G): Male tergite IX unpigmented, with shallow median U-shaped notch, with additional shallow sublateral notch on either side creating sinuous appearance. Ventral branch of gonocoxite wide. Dorsal branch of gonocoxite long, almost as long as ventral branch. Lobe of gonostylus with rounded lobule; lobule as long as wide, shorter than half-length of lobe of gonostylus, wider than stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch curved, club-shaped. Mesal lobes of gonocoxite asymmetrical, both elongated and slightly rounded at posterior margin; left mesal lobe wider than right. Sheath of aedeagus straight, dark almost entire length.

We could not examine the holotype, but the paratypes were examined. This species resembles A. (R.) chiloeanus Alexander but differs mainly in the attachment of m-cu, length of female cercus, shape of male tergite IX, sheath of aedeagus and mesal lobe.

Holotype: ♂, Chile, Osorno, Pucotrihue [40°32′S 73°42 W], 10/12-IV-1968, Peña (USNM)*. Paratypes: 1 ♂, Chile, Osorno, Bahia Mansa [40°35′S 73°44′W], South of Pucotrihue, 12-IV-1968, Peña (USNM); 2 ♂, Chile, Chaihuin [39°56′S 73°34′W], 810 m, 20-III-1955, Peña (USNM). — Additional material: CHILE. 2 ♀ and 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 1/3-II-1952, Peña (USNM); 2 [sex unknown], Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, L.P. Guzman (USNM); 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM); 1 [sex unknown], Chiloé Is., Aucar [42°9′S 73°30′W], 15-I-1952, L.P. Guzman (USNM).

The word immaculatus is Latin for “unstained”. The term refers to the fact that the wing has no pterostigma or markings.

This species is characterized by having sinuous cross-vein m-cu and no markings near R₂. Furthermore, the species is characterized by male terminalia with a curved sheath of aedeagus and right mesal lobe similar in shape, but longer than left one, and scutellum rounded in lateral view.

Wing length 6.22 mm, width 1.74 mm. — Coloration: General coloration brownish-yellow. Rostrum and palpus dark brown. First segments of antenna yellow, remainding segments dark yellow. Head dark brown. Eye black. Thorax brownish yellow, pleura pale. Scutum without stripes. Halter brownish-yellow. Coxae brownish yellow and legs brown. Abdomen blackish brown. — Head (dorsal view Fig. 19B, ventral view Fig. 19A): Rostrum bifurcated with short appendices; first palpal segment as long as terminal segment; scape as thick as pedicel; terminal flagellomere as long as penultimate. — Thorax (lateral view Fig. 19E, dorsal view Fig. 19F): Short setae on prescutum. Division line of laterotergite almost vertical; anatergite taller than katatergite. Halter with dilated knob. Wing (Fig. 19D) without markings; veins near fork of bM (Fig. 19C) visible; M₁₊₂ as long as M₁; R₂₊₃₊₄ longer than R₂₊₃; wing very light on pigmentation, almost translucent. — Female terminalia (Fig. 19H): Female tergite IX shorter and as wide as tergite X; cercus slightly curved dorsad. — Male terminalia (Fig. 19G): Male tergite IX slightly darkened along posterior margin, with deep V-shaped median notch; posterolateral lobes of triangular shape with rounded tips. Ventral branch of gonocoxite expanded in distal tip. Dorsal branch of gonocoxite half-length of ventral branch, curved ventrally. Lobe of gonostylus with rounded lobule; lobule longer than wide, longer than half-length of lobe of gonostylus, wider than stem. Clasper of gonostylus with similarly shaped branches: lateral branch rounded, narrow; medial branch wider, oblong. Mesal lobes of gonocoxite symmetrical; both straight with slightly bent pointed tip. Sheath of aedeagus curved halfway and darkened only near tip.

Some specimens of this new species were previously identified by C.P. Alexander as A. (R.) sanus Alexander, some as A. (R.) nullus Alexander and some as A. (R.) nonnullus Alexander. This species resembles A. (R.) billighami sp. nov. but differs mainly in attachment of m-cu, setae concentration in gonocoxite, shape of male tergite IX and right mesal lobe.

Holotype: ♂, Chile, Malleco, Rio Blanco [38°23′S 71°48′W], 5/27-III-1951, Peña, Holotype 9362 (USNM) [part of specimen pinned and part on slide prepared by C.P. Alexander]. — Additional material: CHILE. 3 [sex unknown], Llanquihue, Carelmapu [41°44′S 73°40′W], Coast North of Canal de Chacao, 18-III-1957, Peña (USNM); 2 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM); 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 10/14-II-1952, Peña (USNM); 1 ♂, Llanquihue, Carelmapu [41°44′S 73°40′W], Coast North of Canal de Chacao, 18-III-1957, Peña (USNM)*; 1 ♂, Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, Peña (USNM)*.

This species is distinguished by only a dark spot near R₂ and a curved m-cu. Furthermore, this species has a remarkable thorax which is as long as tall and characteristic male terminalia with the sheath of aedeagus with a rectangular spur and the tip of left mesal lobe curved.

Wing length 6.75 mm, width 2.04 mm. — Coloration: General coloration brown. Rostrum and palpus brown. First segment of antenna yellow, remaining segments dark yellow. Head brown. Eyes black. Thorax brown, pleura yellowish brown. Scutum with one black stripe. Halter pale with knob ochreous. Coxae and legs yellowish-brown. — Head (dorsal view Fig. 20A): Rostrum bifurcated with short appendices; first palpal segment slightly shorter than terminal segment; scape thinner than pedicel, terminal flagellomere longer than penultimate. Thorax (lateral view Fig. 20D, dorsal view Fig. 20E): Thorax wider than long, with compressed aspect, with larger membranous area. Anepisternum and anepimerum short; prothorax wide. Anatergite as tall as katatergite. Halter with dilated knob. Wing (Fig. 20C) almost clear of markings, except for strong marking covering R₂; veins near bM fork faded (Fig. 20D); M₁₊₂ shorter than basal deflection of M₁; r-m at least 1.25× longer than combined length of M₁₊₂ and basal deflection of M₁; R₂₊₃ longer than R₂₊₃₊₄. — Male terminalia (Fig. 20F): Male tergite IX faintly darkened on posterior margin, with wide V-shaped median notch; posterolateral lobes nearly triangular. Dorsal branch of gonocoxite poorly developed. Lobe of gonostylus with round-shaped lobule, longer than wide; lobule longer than half-length of lobe of gonostylus, as wide as stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch ovoid. Mesal lobes of gonocoxite asymmetrical; left mesal lobe elongated, curved; right mesal lobe with sharp turn. Sheath of aedeagus straight, darkened on distal portion, narrowed at tip with preapical, nearly rectangular extension.

This species resembles A. (R.) alexanderi sp. nov. but differs mainly in attachment of m-cu, length of r-m, shape of thorax, mesal lobe and sheath of aedeagus.

Holotype: ♂, Chile, Chiloé Is., Dalcahue [42°22′S 73°39′W], 1/4-IV-1968, Peña (USNM)*. Paratypes: 1 ♂, Chile, Osorno, Pucotrihue [40°32′S 73°42′W], 60 m, 10-III-1958, Peña (USNM)*; 1 ♂, Chile, Chiloé Is., Dalcahue [42°22′S 73°39′W], 10/12-II-1954, Peña (USNM)*; 1 ♂, Chile, Arauco, Nahuelbuta, Butamalal [37°49′S 73°14′W], 1100–1400 m, 23/31-I-1954, Peña (USNM)*. — Additional material: CHILE. 1 ♀ and 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM); 1 [sex unknown], Chiloé Is., Dalcahue [42°22′S 73°39′W], 1/4-IV-1968, Peña (USNM).

The species is named after Charles Morphy D. dos Santos, a Brazilian entomologist who studied the taxonomy and biogeography of South American Diptera.

This species is distinguished by only a marking near R₂, and basal deflection of R₅ shorter than half-length of R₂₊₃₊₄. Furthermore, the species is characterized by male terminalia with a triangular spur, tip of left mesal lobe bent, tip of right mesal lobe slightly curved and cercus thin and abruptly curved.

Wing length 5.63 mm, width 1.74 mm. — Coloration: General coloration yellowish brown. Rostrum and palpus dark brown. First segments of antenna yellow, remainding segments dark yellow. Head blackish brown. Eyes black. Thorax yellowish-brown, pleura yellow. Scutum with one reddish-brown stripe. Halter dark yellow with knob pale. Coxae and legs brownish yellow. Abdomen dark brown. — Head (dorsal view Fig. 21B, ventral view Fig. 21A): Rostrum bifurcated with long appendices; first palpal segment shorter than terminal segment; scape thinner than pedicel; terminal flagellomere as long as penultimate. — Thorax (lateral view Fig. 21E, dorsal view Fig. 21F): Anatergite shorter than katatergite. Halter with dilated knob. Wing (Fig. 21D) almost clear of markings, except for marking highlighting R₂; veins near fork of bM (Fig. 21C) visible; basal deflection of R₅ as long as r-m; M₁₊₂ half-length of basal deflection of M₁; R₂₊₃₊₄ shorter than R₂₊₃. — Female terminalia (Fig. 21H): Female tergite IX wider and as long as tergite X; cercus curved and abruptly dorsad. — Male terminalia (Fig. 21G): Male tergite IX slightly darkened along dorsal margin, with wide V-shaped median notch. Ventral branch of gonocoxite long. Lobe of gonostylus with rounded lobule; lobule longer than wide, longer than half-length of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch curved. Mesal lobes of gonocoxite asymmetrical; left mesal lobe with posterior projection anvil-shaped; right mesal lobe curved. Sheath of aedeagus straightened with conical projection, darkened only at tip.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) insanus Alexander. This species resembles A. (R.) amorimi sp. nov. but differs mainly in chaetotaxy of the thorax and gonocoxite, length of R₂₊₃₊₄ and shape of mesal lobe.

Holotype: ♂, Chile, Chiloé Is., Aucar [42°9′S 73°30′W], 6/15-I-1952, Peña, Holotype 9619 (USNM) [part of specimen pinned and part in slide prepared by C.P. Alexander]. — Additional material: CHILE. 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM)*; 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 1/3-II-1952, Peña (USNM)*.

This species is distinguished by R₂ without a dark spot and the beginning of M₁ desclerotized. Furthermore, the species has a distinctive male terminalia with a curved sheath of aedeagus with the branches of the clasper of different sizes.

Wing length 5.58 mm, width 1.71 mm. — Coloration: General coloration brownish-yellow. Rostrum and palpus dark brown. First segment of antenna yellow, remaining segments brownish-yellow. Head brown. Eyes grayish black. Thorax brownish yellow, pleura grayish-yellow. Scutum with one brownish-black stripe. Halter light yellow. Coxae light yellow; legs yellowish-brown. Abdomen yellowish brown. — Head (dorsal view Fig. 22B, ventral view Fig. 22A): Rostrum bifurcated with short appendices; first palpal segment shorter than terminal segment; scape thinner than pedicel, terminal flagellomere as long as penultimate. — Thorax (lateral view Fig. 22E, dorsal view Fig. 22F). Laterotergite almost triangular, anatergite taller than katatergite. Halter with dilated knob. Wing (Fig. 22D) without distinctive markings; veins near fork of bM (Fig. 22C) faded; m-cu inserted distal to fork of bM; M₁₊₂ shorter than basal deflection of M₁; R₂₊₃ longer than R₂₊₃₊₄. — Male terminalia (Fig. 22G): Male tergite IX slightly darkened on distal margin, with wide median U-shaped notch; posterolateral lobes rounded. Dorsal branch of gonocoxite half-length of ventral branch; both branches setose. Lobe of gonostylus with rounded lobule; lobule about as long as half-length of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch curved, club-shaped. Mesal lobes of gonocoxite asymmetrical; both mesal lobes with sharp, 90° turn on posterior end; right mesal lobe significantly longer than left. Sheath of aedeagus curved, darkened only at distal portion.

This species resembles A. (R.) apiculatus Alexander but differs mainly in the fork of bM, shape of male tergite IX, clasper of gonostylus and mesal lobe.

Paratypes: 1 ♂, Argentina, Nahuel Huapi, Lago Correntoso [40°42′S 71°39′W], 2-XI-1926, R.C. Shannon (USNM)*; 1 ♂, Chile, Puerto Varas [41°19′S 72°59′W], 16-XII-1926, F. & M. Edwards (USNM)*. — Additional material: CHILE. 1 ♂, 1 ♀ and 2 [sex unknown], Arauco, Nahuelbuta [37°46′S 72°59′W], 5/10-II-1953, Peña (USNM)*; 2 [sex unknown], Cautin, Villarica [39°27′S 71°54′W], 30 Km. NE, 1/30-I-1965, Peña (USNM)*; 2 ♂ and 1 [sex unknown], Chiloé Is. Ancud [41°52′S 73°48′W], 23-I-1952, L.P. Guzman (USNM)*; 1 ♀ and 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM)*; 1 [sex unknown], Arauco, Nahuelbuta, Butamalal [37°49′S 73°14′W], 1100–1400 m, 23/31-I-1954, Peña (USNM)*; 1 [sex unknown], Cordillera las Raices [38°31′S 71°28′W], West of Lonquimay, 1500 m, 28-XII-1967, Peña (USNM)*; 2 ♂, Chiloé Is. Ancud [41°52′S 73°48′W], 23-I-1952, Peña (USNM); 2 ♂, Casa Pangue [41°03′S 71°51′W], 6/10-XII-1926, F. & M. Edwards (USNM); 2 ♂, Cautin, Villarica [39°27′S 71°54′W], 30 Km. NE, 1/30-I-1965, Peña (USNM); 1 ♂, Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM); 1 ♂, Llanquihue, Hornohuinca [41°25′S 72°37′W], South of Volcan Calbuco, III-1968, Peña (USNM); 1 ♂, Chiloé Is., Chepu [42°2′S 74°1′W], 4/6-IV-1968, Peña (USNM); 1 ♂, Osorno, Pucotrihue [40°32′S 73°42′W], 60 m, 1/13-III-1955, Peña (USNM); 1 ♂, Caramavida [37°40′S 73°20′W], 1000 m, 5/10-II-1953, Peña (USNM); 1 ♂, Cordillera las Raices [38°31′S 71°28′W], West of Lonquimay, 1500 m, 28-XII-1967, Peña (USNM).

The species is distinguished by the darkened distal quarter of the wings and M₁₊₂ longer than half the length of the basal deflection of M₁. Furthermore, the species has a distinctive clasper of gonostylus with setae on medial branch and straightened lateral branch.

Wing length 6.10 mm, width 1.92 mm. — Coloration: General coloration brown. Rostrum and palpus dark brown. First segments of antenna brownish yellow, remaining segments brown. Head dark brown. Eyes black. Thorax reddish-brown, pleura brown. Three brown stripes on scutum. Halter yellowish brown. Coxae and legs brownish yellow. Abdomen brown. — Head (ventral view Fig. 23A, dorsal view Fig. 23B): Rostrum bifurcated with short appendices; first palpal segment shorter than terminal segment; scape narrower than pedicel, terminal flagellomere as long as penultimate; antenna with several long setae. — Thorax (lateral view Fig. 23E, dorsal view Fig. 23F): Anatergite as tall as katatergite. Halter with dilated knob. Wing (Fig. 23D) with several markings, including faint markings on A₁ and beginning of Rs; markings highlighting m-cu and R₂₊₃₊₄; stronger markings on R₂ and near tip of R₁; distal quarter of wing darkened; veins near fork of bM (Fig. 23C) faded; M₁₊₂ longer in length than half-length of basal deflection of M₁; R₂₊₃₊₄ about same length as R₂₊₃. — Female terminalia (Fig. 23H): Female tergite IX longer and wider than tergite X. Hypogynial valve slender, longer than cercus. Cercus strongly curved dorsad. — Male terminalia (Fig. 23G): Male tergite IX unpigmented, with shallow curved median U-shaped notch. Dorsal branch of gonocoxite long, ca. 0.75 times length of ventral branch. Lobe of gonostylus with rounded lobule, lobule as long as wide, shorter than half-length of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches; lateral branch straight, medial branch curved, club-shaped, with concentration of setae. Mesal lobes of gonocoxite asymmetrical, both with posterior margin rounded with bump on side; right mesal lobe wider. Sheath of aedeagus angulated, darkened through half its length.

We could not observe the holotype, but the paratypes were examined. This species resembles A. (R.) deceptus sp. nov. but differs mainly in shape of branches of the clasper, male tergite IX, mesal lobes and the sheath of the aedeagus.

Holotype: ♂, Chile, Chiloé Is., Aulen, Duhatao [41°58′S 74°02′W], 6/8-II-1952, Peña, Holotype 9620 (USNM) [part of specimen pinned and part in slide prepared by C.P. Alexander]. Allotype: 1 ♀, Chile, Chiloé Is., Aulen, Duhatao [41°58′S 74°02′W], 6/8-II-1952, Peña (USNM). — Additional material: CHILE. 1 ♂ and 2 [sex unknown], Osorno, Bahia Mansa [40°35′S 73°44′W], South of Pucotrihue, 12-IV-1968, Peña (USNM); 1 ♂, Pucotrihue [40°32′S 73°42′W], 10–60 m, 12-III-1955, Peña (USNM); 1 [sex unknown], Osorno, Pucotrihue [40°32′S 73°42′W], 10/12-IV-1968, Peña (USNM); 1 ♂, Chiloé Is., Aucar [42°9′S 73°30′W], 15-I-1952, Peña (USNM)*; 1 ♂, Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, L.P. Guzman (USNM)*; 1 ♂, Pucotrihue [40°35′S 73°44′W], 10-60 m, 12-III-1955, Peña (USNM)*; 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 14-II-1952, Peña (USNM)*; 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 4/6-IV-1952, Peña (USNM)*; 1 ♂, Osorno, Bahia Mansa [40°35′S 73°44′W], South of Pucotrihue, 12-IV-1968, Peña (USNM)*.

The species is distinguished by absence of markings near R₂, cross-vein m-cu attached to M₃₊₄ and length of r-m twice length of basal deflection of R₅. Furthermore, the species has distinctive male terminalia with a curved sheath of aedeagus, both mesal lobes with folded tips and branches of clasper of gonostylus of similar sizes. The species further distinguished also by the combination of sheath of aedeagus with small markings and male tergite IX pigmented. Furthermore, females of this species have the thickest cercus of the subgenus.

Wing length 6.32 mm, width 1.76 mm. — Coloration: General coloration brownish-yellow. Rostrum and palpus dark brown. First segment of antenna yellow, remainding segments dark yellow. Head grayish brown. Eyes black. Thorax brownish yellow, pleura brownish-yellow. Scutum without stripes. Halter yellow. Coxae and legs yellow. Abdomen brown. — Head (dorsal view Fig. 24B, ventral view Fig. 24A): Head wide, rostrum bifurcated with long appendices, first palpal segment longer than dilated terminal segment; scape as thick as pedicel, terminal flagellomere longer than penultimate. — Thorax (lateral view Fig. 24E, dorsal view Fig. 24F): Anatergite shorter than katatergite. Halter with dilated knob. Wing (Fig. 24D) clear, without distinct markings; veins near fork of bM (Fig. 24C) visible; R₂ partially faded; crossvein r-m longer than basal deflection of R₅; M₁₊₂ about same length of M₁₊₂; R₂₊₃₊₄ longer than R₂₊₃. — Female terminalia (Fig. 24H): Female tergite X longer than tergite IX, tergite IX wider. Cercus thick, longer than hypoginial valves, slightly curved dorsad. — Male terminalia (Fig. 24G): Male tergite IX darkened on posterior margin, with V-shaped median notch. Ventral branch of gonocoxite expanded in distal section. Dorsal branch of gonocoxite half-length of ventral branch. Lobe of gonostylus with round lobule; lobule longer than wide, longer than half length of lobe of gonostylus, wider than stem. Clasper of gonostylus with similarly shaped branches: lateral branch nearly oval: medial branch distally flattened, narrowed at margin. Mesal lobes of gonocoxite asymmetrical, both hook-shaped; left mesal lobe narrower. Sheath of aedeagus angulated, darkened only at tip.

This species resembles A. (R.) falcatus sp. nov. but differs mainly in the attachment of m-cu, shape of male tergite IX, prescutum and left mesal lobe.

Holotype: ♂, Chile, Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM)*. Paratypes: 1 ♂, Chile, Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM)*; 1 ♂, Chile, Llanquihue, Carelmapu [41°44′S 73°40′W], Coast of Canal de Chacao, 18-III-1957, Peña (USNM)*; 1 ♂, Chile, Osorno, Bahia Mansa [40°35′S 73°44′W], South of Pucotrihue, 12-IV-1968, Peña (USNM)*.

The species is named after Pjotr Oosterbroek, an important Tipulomorpha expert.

This species is distinguished by only a dark spot on R₂, basal deflection of R₅ as long as r-m, and M₁₊₂ longer than basal deflection of M₁. Furthermore, this species is characterized by male terminalia with sheath of aedeagus with a triangular spur and the tip of sheath inclined.

Wing length 5.47 mm, width 1.68 mm. — Coloration: General coloration brown. Rostrum and palpus brown. First segments of antenna yellow, remainding segments yellowish brown. Head brown. Abdomen yellowish brown. — Head (dorsal view Fig. 25B, ventral view Fig. 25A): Rostrum bifurcated with long appendices; first palpal segment shorter than terminal segment; scape narrower than pedicel; terminal flagellomere dilated. — Thorax: Wing (Fig. 25D) almost clear of markings, except for marking on R₂; veins near fork of bM (Fig. 25C) faded; M₁₊₂ 2.5× longer than basal deflection of M₁; R₂₊₃₊₄ longer than R₂₊₃. — Male terminalia (Fig. 25E): Male tergite IX slightly darkened along posterior margin, with deep median U-shaped notch. Ventral branch of gonocoxite slender, very long, setose on distal tip. Lobe of gonostylus with rounded lobule; lobule longer than wide, shorter than half of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch curved. Mesal lobes of gonocoxite asymmetrical; left mesal lobe curved; right mesal lobe short with sharp turn. Sheath of aedeagus straightened, with wide rectangular projection; darkened only near tip.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) insanus Alexander. This species resembles A. (R.) podenasi sp. nov. but differs mainly in the length of r-m, concentration of setae on gonocoxite, shape of male tergite IX and right mesal lobe.

Holotype. ♂, Chile, Arauco, Nahuelbuta, Pichinahuel [37°48′S 73°02′W], 1400–1600 m, 12/20-II-1953, Peña (USNM)*. Paratypes: 1 ♂, Chile, Chiloé Is., Rio Coluco [42°6′S 73°55′W], 30-I-1952, Peña (USNM)*; 1 ♂, Chile, Llanquihue, Carelmapu [41°44′S 73°40′W], Coast North of Canal de Chacao, 18-III-1957, Peña (USNM)*. — Additional material: CHILE. 1 ♀ and 1 [sex unknown], Chiloé Is., Dalcahue [42°22′S 73°39′W], II-1954, Peña (USNM); 1 [sex unknown], Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, L.P. Guzman (USNM); 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM).

The species is named after Sigitas Podenas, a skilled Tipulomorpha expert.

This species is distinguished by only a dark spot on R₂ and basal deflection of R₅ longer than r-m. Furthermore, this species is characterized by male terminalia with sheath of aedeagus with a spur, tip of right mesal lobe curved downwards and sheath of aedeagus with rounded spur.

Wing length 5.73 mm, width 1.83 mm. — Coloration: General coloration brownish-yellow. Rostrum and palpus brown. First segment of antenna yellow, remainding segmens dark yellow. Head dark brown. Eyes black. Thorax brownish yellow, pleura pale. Contrasting golden setae on prescutum. Scutum without stripes. Halter brownish-yellow. Coxae and legs brownish yellow. Abdomen dark brown. — Head (dorsal view Fig. 26B, ventral view Fig. 26A): Rostrum bifurcated with long appendices; first palpal segment shorter than terminal segment; scape thinner than pedicel; flagellomeres gradually reducing in length, resulting in shorter terminal flagellomeres. — Thorax (lateral view Fig. 26E, dorsal view Fig. 26F): Thorax with several setae, including long setae on prescutum. Anatergite shorter than katatergite. Halter with dilated knob. Wing (Fig. 26D) almost clear of markings, except for strong marking covering R₂; veins near fork of bM (Fig. 26C) faded; M₁₊₂ longer than basal deflection of M₁; R₂₊₃₊₄ shorter than both R₂₊₃ and basal deflection of R₅. — Female terminalia (Fig. 26H): Female tergite IX longer and wider than tergite X; cercus shorter than hypoginial valves, curved dorsad. Both cercus and hypogynial valve very slender. — Male terminalia (Fig. 26G): Male tergite IX slightly darkened along posterior margin, with wide V-shaped median notch. Ventral branch of gonocoxite inclined medially in distal tip. Dorsal branch of gonocoxite nearly half-length of ventral branch. Lobe of gonostylus with rounded lobule; lobule longer than wide, longer than half-length of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch curved, club shaped. Mesal lobes of gonocoxite asymmetrical; left mesal lobe short with sideways projection; right mesal lobe curved. Sheath of aedeagus straightened, with rounded projection; darkened only on tip.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) insanus Alexander. This species resembles A. (R.) oosterbroeki sp. nov. but differs mainly in the length of r-m, concentration of setae on the gonocoxite, shape of male tergite IX and right mesal lobe.

Holotype: ♂, Chile, Valdivia, Enco [39°53′S 72°8′W], 1400–1600 m, 6-III-1955, Peña, Holotype 12226 (USNM) [part of specimen pinned and part in slide prepared by C.P. Alexander]. — Additional material: CHILE. 1 ♂ and 1 [sex unknown], Arauco, Nahuelbuta [37°46′S 72°59′W], 13/20-II-1958, Peña (USNM); 1 [sex unknown], Caramavida [37°40′S 73°20′W], 1000–1300 m, 1/6-I-1954, Peña (USNM); 1 [sex unknown], Lonquimay West, Cordillera las Raices [38°31′S 71°28′W], 1500 m, 25-XII-1968, Peña (USNM); 1 ♂, Lonquimay West, Cordillera las Raices [38°31′S 71°28′W], 1500 m, 25-XII-1968, Peña (USNM)*.

This species is distinguished by a dark spot near R₂ and m-cu inserted at fork of bM. Furthermore this species is distinguished by the male terminalia with the lobule with two rounded margins forming heart shape, sheath of aedeagus is straight but without spurs and the mesal lobes are symmetrical, with slender, bare and slightly curved tips.

Wing length 6.87 mm, width 2.00 mm. — Coloration: General coloration dark brown. Rostrum and palpus dark brown. First segment of antenna light yellow, remainding segments dark yellow. Head brown. Eyes black. Thorax yellowish-brown, pleura light brown. Scutum without stripes. Halter brownish-yellow. Coxae brownish yellow and legs dark brown. Abdomen dark brown. — Head (Fig. 27A): Rostrum bifurcated with long appendices; first palpal segment slightly shorter than terminal segment; scape thicker than pedicel, terminal flagellomere as long as penultimate, antenna with numerous setae. — Thorax (lateral view Fig. 27D, dorsal view Fig. 27E): Thorax with several long setae. Anatergite taller than katatergite. Halter with dilated knob. Wing (Fig. 27C) almost clear of markings, except for marking covering R₂; veins near bM (Fig. 27B) faded; m-cu inserted at fork of bM; M₁₊₂ shorter than basal deflection of M₁; R₂₊₃₊₄ longer than R₂₊₃. — Male terminalia (Fig. 27F): Male tergite IX faintly darkened at posterior margin, with wide V-shaped median notch; posterolateral lobes nearly triangular; ventral branch slender, with concentration of setae on distal tip. Dorsal branch of gonocoxite shorter than half length of ventral branch. Lobe of gonostylus with heart-shaped lobule, more than twice as wide as lobe of gonostylus. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch curved, oblong-shaped. Mesal lobes of gonocoxite symmetrical, both with narrow, elongate, straight extremity. Sheath of aedeagus straight, slightly bent near tip, darkened at distal one-third.

Some specimens of this species were misidentified by C.P. Alexander as A. (R.) insanus Alexander. This species resembles A. (R.) glabristylatus Alexander but differs mainly in the attachment of m-cu, wing markings, shape of male tergite IX and mesal lobe.

Holotype: 1 ♂, Chile, Chiloé Is., Ancud [41°52′S 73°48′W], 1927, F. & M. Edwards (BMNH). — Additional material: CHILE. 2 [sex unknown], Osorno, Pucotrihue [40°32′S 73°42′W], 10/12-IV-1968, Peña (USNM); 1 [sex unknown], Chiloé Is., Dalcahue [42°22′S 73°39′W], II-1954, Peña (USNM); 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 4/6-IV-1968, Peña (USNM); 1 [sex unknown], Osorno, Bahia Mansa [40°35′S 73°44′W], South of Pucotrihue, 12-IV-1968, Peña (USNM); 1 ♂, Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, Peña (USNM)*.

This species is distinguished by a subtle spot on R₂. Furthermore, this species has a remarkable sheath of aedeagus with a long horizontal spur, male tergite IX with a distinctive rectangular projection, mesal lobes absent and posterior margin of male tergite IX pigmented.

Wing length 5.86 mm, width 1.90 mm. — Coloration: General coloration dark brown. Rostrum and palpus dark brown. Antenna yellow, with apical segments slightly darker. Head brown. Eyes black. Thorax dark brown, pleura brown. Scutum without stripes. Halter brownish-yellow. Coxae brownish yellow and legs dark brown. Abdomen dark brown. — Head (dorsal view Fig. 28B, ventral view Fig. 28A): Rostrum bifurcated with short appendices; first palpal segment shorter than terminal segment, terminal palpal segment dilated; scape narrower than pedicel; terminal flagellomere shorter and thicker than penultimate; antenna with several long setae. — Thorax (lateral view Fig. 28E, dorsal view Fig. 28F): Anatergite taller than katatergite. Prothorax wide, prescutum with a few short setae. Halter with dilated knob. Wing (Fig. 28D) almost clear of markings, except subtle marking on R₂; veins around fork of bM (Fig. 28C) faded; M₁₊₂ longer than basal deflection of M₁; R₂₊₃₊₄ longer than R₂₊₃. — Male terminalia (Fig. 28G): Male tergite IX darkened on posterior margin, with wide median U-shaped notch; rectangular projection in two points on either side of extension; posterior margin with projection flat. Dorsal branch of gonocoxite very reduced. Lobe of gonostylus with pointed lobule shaped similar to folded leaf. Clasper of gonostylus with differently shaped branches: lateral branch long, bent around middle; medial branch curved into short stub. Mesal lobes absent. Sheath of aedeagus dark along almost entire length, angulated with smooth curvature, with setae on distal portion of lateral margin, as well as large distal horizontal lateral projection.

Some specimens were misidentified by C.P. Alexander as A. (R.) nullus Alexander. The rostrum of the holotype is longer than in the other species of this subgenus. This species resembles A. (R.) anchoralis sp. nov. but differs mainly in M₁₊₂, shape of projection on male tergite IX, ventral branch of gonocoxite and spur of sheath of aedeagus.

Holotype: ♂, Chile, Llanquihue, Hornohuinca [41°25′S 72°37′W], XII-1968, Peña (USNM)*. Paratypes: 1 ♀ and 1 [sex unknown], Chile, Arauco, Nahuelbuta [37°46′S 72°59′W], 5/10-II-1953, Peña (USNM); 1 ♂, Chile, Chiloé Is., Chepu [42°2′S 74°1′W], 4/6-IV-1968, Peña (USNM)*. — Additional material: CHILE. 2 ♂, Pucotrihue [40°32′S 73°42′W], 60 m, 10-III-1955, Peña (USNM); 1 male and 1 ♀, Chiloé Is. Ancud [41°52′S 73°48′W], 17-XII-1926, Peña (USNM); 1 ♂, Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, L.P. Guzman (USNM); 1 ♂ and 1 [sex unknown], Pucotrihue [40°32′S 73°42′W], 60 m, 1/13-III-1955, Peña (USNM); 1 [sex unknown], Llanquihue, Hornohuinca [41°25′S 72°37′W], South of Volcan Calbuco, 30/31-III-1968, Peña (USNM); 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 1/3-II-1952, Peña (USNM); 1 male and 1 [sex unknown], Arauco, Nahuelbuta [37°46′S 72°59′W], 5/10-II-1953, Peña (USNM); 1 ♀, Casa Pangue [41°03′S 71°51′W], 4-XII-1926, R. C. Shannon (USNM); 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM); 1 [sex unknown], Chiloé Is., Aulen [42°2′S 74°1′W], 4-II-1952, Peña (USNM); 1 ♀ and 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 4/6-IV-1968, Peña (USNM); 1 ♂, Arauco, Nahuelbuta, Caramavida [37°40′S 73°20′W], 1000 m, 5/10-II-1953, Peña (USNM)*; 1 ♂, Chiloé Is., Chaiten [42°58′S 72°32′W], 5/8-II-1954, Peña (USNM)*; 1 ♂, Chiloé Is., Chepu [42°2′S 74°1′W], 1/3-II-1951, Peña (USNM)*.

The word stigmaticus is Latin for “marked”. The term refers to the darkened mark near the tip of the wing of this new species.

This species is distinguished by the darkened distal quarter of the wings and basal deflection of M₁ shorter than M₁₊₂. Furthermore, the species is characterized by the male terminalia with setae on the medial branch of clasper of gonostylus and small marking on sheath of aedeagus.

Wing length 7.48 mm, width 2.57 mm. — Coloration: General coloration dark brown. Rostrum and palpus dark brown. First segment of the antenna yellow, remainding segments dark yellow. Head dark brown. Eye gray. Thorax dark brown, pleura brown. Scutum with three brownish black stripes. Halter pale. Coxae and legs brownish yellow. Abdomen dark brown. — Head (dorsal view Fig. 29B, ventral view Fig. 29A): Rostrum bifurcated with short appendices; first palpal segment shorter than terminal segment; palpus with several setae; scape thicker than pedicel; terminal flagellomere as long as penultimate. — Thorax (lateral view Fig. 29E, dorsal view Fig. 29F): Scutum with two rows of short setae; anatergite shorter than katatergite. Halter with dilated knob. Wing (Fig. 29D) with several markings including faint marking on A₁; markings highlighting m-cu, r-m, part of R₅, and R₂₊₃; marking on Rs, darkened distal quarter of wing and strong markings on R₂ and at tip of R₁; veins near fork of bM (Fig. 29C) faded; M₁₊₂ longer than basal deflection of M₁; R₂₊₃₊₄ shorter than half-length of R₂₊₃. — Female terminalia (Fig. 29H): Female tergite IX as wide and longer than tergite X; hypogynial valve slender; cercus bent at right angle, expanded in base; cercus shorter than hypogynial valve. — Male terminalia (Fig. 29G): Male tergite IX with shallow median U-shaped notch. Dorsal branch of gonocoxite longer than half-length of ventral branch, well separated from ventral branch. Lobe of the gonostylus rounded; lobule longer than wide, shorter than half-length of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch straightened; medial branch curved, round club shaped, with concentration of setae. Mesal lobes of gonocoxite symmetrical; both rounded with bump on side. Sheath of aedeagus angulated, darkened only near tip.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) nothofagetorum Alexander. This species resembles A. (R.) caleuchus sp. nov. but differs mainly in marking in the sheath of aedeagus, length of R₂₊₃₊₄, shape of lobe of gonostylus, cercus and mediotergite.

Holotype: ♂, Chile, Osorno, Pucotrihue [40°32′S 73°42′W], 10/12-IV-1968, Peña (USNM)*. Paratypes: 2 ♂ and 1 ♀, Chile, Osorno, Bahia Mansa [40°35′S 73°44′W], South of Pucotrihue, 12-IV-1968, Peña (USNM).

The species is named after Gunther Theischinger, an expert on Tipulomorpha who revised the Australian Amphineurus.

This species is distinguished by an absence of markings near R₂, r-m as long as basal deflection of R₅, and cross-vein m-cu straight and inserted at bM. Furthermore, this species is characterized by male terminalia with curved sheath of aedeagus, straight medial branch of clasper of gonostylus and mesal lobes with slender, vertical tips. The thorax is also distinguishable by narrow knob of halter and katepisternum as long as meron.

Wing length 6.30 mm, width 1.77 mm. — Coloration: General coloration dark brown. Rostrum and palpus brownish black. First segment of antenna yellow, remainding segments dark yellow. Head brownish gray. Eye black. Thorax dark-brown, pleura light brown. Scutum without stripes. Halter brownish-yellow. Coxae brownish-yellow, legs dark brown. Abdomen brownish black. — Head (dorsal view Fig. 30B, ventral view Fig. 30A): Rostrum bifurcated with short appendices; first palpal segment shorter than terminal segment; scape thinner than pedicel; terminal flagellomere longer than penultimate. — Thorax (lateral view Fig. 30E, dorsal view Fig. 30F): Anatergite shorter than katatergite. Halter with narrow knob. Wing (Fig. 30D) clear of distinctive markings; veins near fork of bM (Fig. 30C) visible; M₁₊₂ longer than basal deflection of M₁; R₂ faded; R₂₊₃₊₄ longer than R₂₊₃. — Female terminalia (Fig. 30H): Female tergite IX shorter and wider than tergite X; hypogynial valve very slender; cercus longer than hypogynial valve, thick, and slightly curved dorsad. — Male terminalia (Fig. 30G): Male tergite IX with V-shaped median notch. Distal tip of ventral branch of gonocoxite expanded, setose, with slight curve ventrally. Dorsal branch of gonocoxite shorter than half-length of ventral branch. Lobe of gonostylus with rounded lobule; lobule longer than wide, more than half as long as lobe of gonostylus, wider than stem. Clasper of gonostylus with similarly shaped branches: lateral branch rounded; medial branch conical. Mesal lobes of gonocoxite asymmetrical; both with long, narrow, straight distal projection; right mesal lobe wider. Sheath of the aedeagus curved halfway along length, darkened only on tip.

Specimens of this new species were previously identified by C.P. Alexander as A. (R.) nullus Alexander. This species resembles A. (R.) billighami sp. nov. but differs mainly in the attachment of m-cu, setae concentration in gonocoxite, shape of male tergite IX and mesal lobe.

Holotype: ♂, Chile, Chiloé Is., Chepu [42°2′S 74°1′W], 8-II-1952, Peña (USNM)*. Paratypes: 1 ♀, Chile, Chiloé Is., Dalcahue [42°22′S 73°39′W], 1/4-IV-1968, Peña (USNM); 1 ♂, Chile, Chiloé Is., Chepu [42°2′S 74°1′W], 10/14-II-1952, Peña (USNM)*. — Additional material: CHILE. 2 ♂ and 1 [sex unknown], Pucotrihue [40°32′S 73°42′W], 60 m, 10-III-1955, Peña (USNM); 1 ♂, 1 ♀ and 1 [sex unknown], Llanquihue, Carelmapu [41°44′S 73°40′W], Canal Chacao, 18-III-1957, Peña (USNM); 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 8-II-1952, Peña (USNM).

The word triangularis is Latin for “triangular”. This name references the triangular shape of the spur of sheath of aedeagus.

This species is distinguished by only a dark spot near R₂ and M₁₊₂ as long as the basal deflection of M₁. Furthermore, this species is characterized by male terminalia with sheath of aedeagus with a triangular spur, tip of both mesal lobes bent horizontally, straightened lateral branch of clasper of gonostylus and cercus uniformly wide and abruptly angled dorsad.

Wing length 5.76 mm, width 1.74 mm. — Coloration: General coloration brownish yellow. Rostrum and palpus dark brown. First segment of antenna yellowish brown, remainding segments brown. Head brown. Eye black. Thorax brownish yellow, pleura pale. Scutum with one black stripe. Halter dark yellow with knob yellowish brown. Coxae yellow and legs brown. Abdomen yellowish brown. — Head (dorsal view Fig. 31B, ventral view Fig. 31A): Rostrum bifurcated with long appendices; first palpal segment shorter than terminal segment; scape thinner than pedicel; terminal flagellomere longer than penultimate. — Thorax (lateral view Fig. 31E, dorsal view Fig. 31F): Division line of laterotergite almost vertical, anatergite as tall as katatergite. Halter with dilated knob. Wing (Fig. 31D) almost clear of markings, except marking on R₂; veins near fork of bM (Fig. 31C) faded; M₁₊₂ as long as basal deflection of M₁; R₂₊₃₊₄ longer than R₂₊₃; basal deflection of R₅ shorter than R₂₊₃. — Female terminalia (Fig. 31H): Female tergite IX shorter, wider than tergite X; cercus bent at right angle. Hypogynial valve slender and longer than cercus. — Male terminalia (Fig. 31G): Male tergite IX slightly darkened along posterior margin, with wide V-shaped median notch. Ventral branch of gonocoxite slightly sinuous, with concentration of setae on distal tip. Dorsal branch of gonocoxite shorter than half-length of ventral branch, slightly inclined medially. Lobe of gonostylus with rounded lobule; lobule longer than wide, longer than half-length of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch curved. Mesal lobes of gonocoxite asymmetrical; left mesal lobe curved; right mesal lobe short with sideways projection. Sheath of aedeagus straight with triangular projection, darkened near tip.

Some specimens of this new species were previously identified by C.P. Alexander as A. (R.) insanus Alexander and some as A. (R.) glabristylatus Alexander. This species resembles A. (R.) podenasi sp. nov. but differs mainly in the length of M₁₊₂ and R₂₊₃₊₄, shape of cercus and ventral branch of gonocoxite.