The specimens (Notorhinus floresi sp. nov. and Notorhinus sp. (MNHNC 8390)) can be placed in the family Siphonorhinidae based on the following characters: Head pyriform, not extended into beak (rostrum) (Figs 3A, 8A); antennae elbowed; antennomere 2 longer than wide (Figs 3B, 8C); gnathochilarium consisting of separate plates (Figs 3G, 8B); anterior margin of collum straight (compare Enghoff et al. 2015; Marek et al. 2016). According to a key provided by Shelley (1996: 23) members of the family Siphonorhinidae lack sensory pits on antennomeres 5 and 6 (see also Marek et al. 2012), as is the case in the specimens studied here (Figs 3E, 8C). However, lack of these sensory pits seems to apply only to the North American genus Illacme (Marek et al. 2012, 2016), the Malagasy genus Madagascarhinus (Wesener 2023) and the South African genus Nematozonium (Shelley and Hoffman 2004), as these sensory pits have been reported for Siphonorhinus (Attems 1930, 1938) and Kleruchus (Attems, 1938).

Notorhinus floresi sp. nov.

Pale, thin and elongated Siphonorhinidae with pyriform heads. In Notorhinus gen. nov. (Figs 2, 7) two backwards projecting spines are situated behind the elevated ozopores (Figs 4E, 8G), and the posterior margin of the metazonite (limbus) carries sculptures in shape of a fluke (tail-fin) (Figs 4D, 8H). Notorhinus gen. nov. differs from all other Siphonorhinidae genera by the absence of sensilla basiconica on antennomere 5 and the arrangement of numerous sensilla basiconica on antennomere 6 in a field not sunken into a sensory pit (Figs 3E, 8C). In Siphonorhinus and Kleruchus (see Attems 1930 for S. pellita; Attems 1938 for Teratognathus (syn. of Siphonorhinus) and Kleruchus) numerous sensilla basiconica are located in sensory pits (Sinnesgruben sensu Attems 1930) on antennomeres 5 and 6. In Illacme few sensilla basiconica are arranged in rows along the apical margin of antennomeres 5 and 6 (Marek et al. 2012, 2016) and in Madagascarhinus sensilla basiconica are arranged in 2 – 3 rows on antennomeres 5 and 6 (Wesener 2023). In Nematozonium no sensory structures are evident on the antennae according to Shelley and Hoffman (2004). Notorhinus gen. nov. differs from Illacme by the fusion of the first legs’ coxae to the sternite (Fig. 3G), forming a coxosternite (see Marek et al. 2012, 2016 for Illacme), as is the case in Siphonorhinus (see Enghoff et al. 2015). Furthermore, the specimens differ from Kleruchus by the presence of an anal scale/hypoproct (Figs 4F, 8I) (Analschuppe sensu Attems 1938).

Several characters are shared with the genus Illacme Cook and Loomis, 1928 (see Marek et al. 2012, 2016 for detailed documentation): antennomeres 5 and 6 longer and wider; antennae elbowed between antennomeres 3 and 4 (Fig. 3B); presence of cluster of spiniform sensilla basiconica (spiniform basiconic sensilla sensu Marek et al. 2016) next to apical sensory cones (Fig. 3F); labrum with incision, lined by teeths; pores of salivary glands arranged in a single circular field above the labrum (Fig. 3C); gonopods with 7 podomeres (Fig. 5E); posterior gonopods apical podomere with three branches: two apically laminate/flattened branches and a single posterior spine-like branch (Fig. 5F). However, some of these characters are not well studied in the remaining genera of the Siphonorhinidae.

Noto is derived from the ancient greek νότος (nótos) meaning south and refers to the distribution of the genus in South America and the fact that it is the most southern record of the family Siphonorhinidae. Rhinus is derived from the ancient Greek ῥῑ́ς (rhī́s; genitive: ῥῑνός (rhīnós)), meaning nose, and refers to the acuminate head shape. Rhinus is often part of taxonomic names in the group (e.g. Siphonorhinidae Cook, 1895, Siphonorhinus Pocock, 1894, Madagascarhinus Wese­ner, 2023).

Small (< 13 mm) elongated Siphonorhinidae with arched metazonites. Body pale, covered by setae, creating a velvety appearance (Fig. 2A). Anterior and posterior gonopods with 7 podomeres (Fig. 5E). Posterior gonopod apically with 3 branches, 2 laminate and 1 spinous (Fig. 5F). Pseudopenis prominent, cone-shaped (Fig. 5B). Posterior margin of metazonite (limbus) with small fluke-shaped sculpture (Fig. 4D). Antennomere 7 with spiniform sensilla basiconica in 2 rows (Fig. 3F) (1 row in Notorhinus sp.). Metazonite posterior margin straight (Fig. 4A) (sinuate in Notorhinus sp.). Differs from Notorhinus sp. (MNHNC 8390) in coloration, number of body-rings and its length relative to the number of body-rings (Fig. 2A): Notorhinus sp. has 80 body-rings but is only 11.5 mm long, while Notorhinus floresi sp. nov. has up to 54 body-rings, but a length of up to 13.8 mm.

Figure 2. 

Notorhinus floresi sp. nov., photographs. A, B Living specimen in its natural habitat. Photographs by Edgardo Flores. C Male paratype (ZFMK-MYR 12267), habitus, lateral view. D Female paratype (ZFMK-MYR 12269), head, lateral view.

Figure 3. 

Notorhinus floresi sp. nov., male holotype (MNHNC 8387), head, SEM. A Head, frontal view. B Head, lateral view. C Labrum, frontal view. D Labrum and gnathochilarium, ventral view. E Apical antennomeres, lateral view. F Apical antennomere, apical view. G Gnathochilarium and leg-pair 1, ventral view. Abbreviations: I–VII = antennomeres, ac = apical cones, cl = claw, co = collum, cx = coxa, ep = epicranium, fe = femur, fh = forehead, ge = genae, in = inscision of the labrum, la = labrum, LL = lamella lingualis, lp = spinous protuberences of labrum, lt = teeth lining labral incision, me = mentum, pa = palp-like structure, po = pores of the salivary glands, pof = postfemur, prf = prefemur, sb = sensilla basiconica, ssb = spiniform sensilla basiconica, sti = gnathochilarial stipes, ta = tarsus, ti = tibia.

Figure 4. 

Notorhinus floresi sp. nov., male holotype (MNHNC 8387), body-rings and legs, SEM. A Mid-body-rings, dorsal view. B Mid-body-rings, lateral view. C Mid-body-rings, ventral view, legs removed. D Metazonite posterior margin (limbus), arrow indicates fluke-shaped sculpture. E Ozopore, lateral view, arrows indicate spines behind ozopore. F Telson, posterior view. G Mid-body leg, anterior view. H Leg 2, tarsal claw, arrow indicates division of tarsal claw. Abbreviations: cl = claw, cs = coxal sac, cx = coxa, fe = femur, hp = hypoproct (subanal scale), mz = metazonite, oz = ozopore, pl = pleurite, pof = postfemur, pp = paraproct (anal valve), pr = preanal ring, prf = prefemur, pz = prozonite, sp = spiracle, st = sternite, ta = tarsus, ti = tibia, tr = trochanter.

Figure 5. 

Notorhinus floresi sp. nov., male holotype (MNHNC 8387), sexual characters, SEM. A Leg 2, ventral view. B Male pseudopenis bearing the gonopore, ventral view. C Male pseudopenis bearing the gonopore, posterior view. D Anterior and posterior gonopods, ventral view. E Anterior and posterior gonopods, ventro-lateral view. F Right anterior and posterior gonopod, detail of the apical podomeres. Abbreviations: a1–a7 = podomeres of the anterior gonopod, cx = coxa, f1 = pointed/spinous branch of the posterior gonopod’s apical podomere, f2 and f3 = laminate branches of the posterior gonopod’s apical podomere, go = pseudopenis carrying the gonopore, p1–p7 = podomeres of the posterior gonopod, st = sternite associated with anterior gonopods.

The species epithet floresi refers to Edgardo Flores, who collected the examined specimens, and honors his continuous engagement in nature conservation and his persistence on the protection of Nahuelbuta National Park and adjacent areas. Noun in genitive.

Holotype: ♂ (MNHNC 8387); CHILE: Biobío, near Caramavida; 37.72698°S 73.19339°W; 21.iix.2019; Edgardo Flores leg. (e23); hand collected under a decaying piece of wood, in a relictual forest surrounded by eucalypt plantations (Fig. 1C, D). — Paratypes: 2 ♂ (ZFMK-MYR 12267, ZFMK-MYR 12268); 3 ♀ (MNHNC 8388, MNHNC 8389, ZFMK-MYR 12269); same data as holotype.

Measurements : Male holotype (MNHNC 8387): br47+T, 12 mm long; male paratype (ZFMK-MYR 12267): br37+T, 8.9 mm; male paratype (ZFMK-MYR 12268): br54+T, 13.8 mm; female paratype (MNHNC 8389: br42+T, 10.7 mm; female paratype (MNHNC 8388): br49+T, 12.8 mm; female paratype (ZFMK-MYR 12269): br47+T, 10.9 mm. Body thread-like, elongate thin, pale white (Fig. 2A–C), in ethanol head lighter in coloration than body (Fig. 2C, D). — Head: Head pyriform, anteriorly tapering, widest behind antennae, covered by long setae (Fig. 3A), posterior and lateral of antennae covered by scale-like sculpture (Fig. 3B). Labrum incised, two lateral spinous protuberances on each side of incision, incision lined by. by up to 5 teeth on each side. Salivary glands opening via > 50 small pores, arranged in a circular field above labrum (Fig. 3C, D). Lateral margin (genae) and anterior margin (labrum) of head capsule straight, tightly appressed to gnathochilarium (Fig. 3B). Antennae inserting laterally in posterior half of head capsule (Fig. 3A), with 7 antennomeres + apical disc, elbowed between antennomeres 3 and 4. Antennomere 6 longest (6 > 2 > 5 > 1 = 3 = 4 > 7), 2 and 6 longer than wide, 1, 3–5 and 7 wider than long, 5 and 6 widest. Each antennomere with several rows of setae (Fig. 3B). Antennomere 5 without sensilla basiconica. Antennomere 6 with ca. 25 sensilla basiconica arranged in a circular field (not sunken into a sensory pit) located laterally in some distance from antennomere’s apical margin (Fig. 3E). Antennomere 7 on apical margin with a lateral group of 8 spiniform sensilla basiconica arranged in two rows, and a single spiniform sensilla basiconica each at anterior and posterior margin, projecting above apical disc between apical cones. Apical disc sunken into antennomere 7 with 4 apical sensory cones, base of apical cones elevated (Fig. 3F). Gnathochilarium triangular, tightly appressed to head capsule consisting of stipites, mentum and lamellae linguales (proximal part not visible). Stipites each with 5 marginal setae, apically with palp-like extension, each with 5 sensilla (Fig. 3D). Mentum with 6 (3+3) setae arranged in 2 longitudinal rows. Lamellae linguales each with 2 short setae, mesal margins apically with hair-like structures (Fig. 3D, G). Mandibles internalized, not visible externally (Fig. 3A, B). — Body-rings: Collum longer than following tergite, covering posterior part of head, anterior margin almost straight. Collum covered by long setae and laterally with scale-like sculpturing (Fig. 3A, B). Each body-ring consisting of free tergite (1), pleurites (2) and sternites (2) (Fig. 4A–C). Body-rings 2–4 shorter than following body-rings. Tergites clearly divided into prozonite and metazonite (Fig. 4A, B). Prozonite narrower than metazonite, covered by circular cylinder/pillar-shaped sculpturing, lateral sculpturing becoming more acuminate, anterior margin with scale-like sculpturing, with few setae along anterior and posterior margin (Fig. 4A, B). Metazonite arched, circular/cylindrical sculpture restricted to anterior and lateral areas, resulting in a crown-shaped smooth dorsal area. Metazonite covered by setae (Fig. 4A, B). Posterior margin of metazonite (limbus) with 2 irregular rows of fluke-shaped sculptures (Fig. 4D). Ozopores from body-ring 5 onwards, positioned laterally in posterior half of metazonite, slightly elevated, surrounded by a ring of setae, with 2 posterior spines and 3 setae between spines (Fig. 4E). Pleurites almost rectangular, anteriorly and posteriorly rounded, laterally slightly curved towards legs. Pleurites anteriorly covered by setae and circular/cylindrical sculptures, posterior lateral sculpturing acuminate, anterior part of pleurite covered by flat scale-like sculptures (Fig. 4C). Sternites rectangular with a transverse elevation projecting between the legs’ coxae. Margins of this elevation with scale-like sculpturing, spiracles located laterally of legs (Fig. 4C). — Telson: Preanal ring ca. as long as preceding body-ring, posteriorly rounded in dorsal view, covered by setae. Cylindrical sculpture restricted to lateral and ventral part and the anterior margin, dorsal surface without sculpture (Fig. 4F). Anal valves (paraprocts) covered by setae, proximally with scale-like sculpturing. Subanal scale (hypoproct) present, with few setae and flat scale-like sculpture (Fig. 4F). — Legs: Leg pairs 1 and 2 with 6 podomeres: coxa, prefemur, femur, postfemur, tibia and tarsus. Coxae of leg-pair 1 fused to sternite (coxosternite) (Fig. 3G). From leg-pair 3 onwards with coxal sacs and short additional podomere (trochanter) between coxa and prefemur: Prefemur = tarsus > femur = coxa > postfemur = tibia > trochanter (Fig. 4G). Coxae almost touching mesally. Podomeres with few long setae (Fig. 4G). Tarsal claw bifurcated, ventral branch ca. 2/3 of length of dorsal branch on anterior legs (Fig. 4H), ventral branch decreasing in size on posterior legs. Last body-ring anterior of telson apodous. — Male sexual characters: Male gonopores on pseudopenes situated posteriorly on coxae of leg-pair 2 (Fig. 5A), pseudopenis knob-like/cone-shaped in ventral view (Fig. 5B), latero-posterior surface excavated with membranous surfaces (Fig. 5C). Leg-pair 9 and 10 modified to leg-like gonopods (Fig. 5D). Anterior gonopods with 7 podomeres, tapering distally. Each podomere with few setae arranged in a row. Podomere 1 with 2 anterior setae, podomere 2 with 1 anterior seta, podomere 3 with 3 anterior setae, podomere 4 with 1 anterior and 1 posterior setae, podomere 5 with 1 lateral and 4 posterior setae, podomere 6 with 2 lateral and 3 posterior setae, podomere 7 with 4 posterior setae (Fig. 5D, E). Apical podomere (7) flap-like, forming a sheath engulfing the tip of the posterior gonopod (Fig. 5F). Posterior gonopod with 7 podomeres, tapering distally. Podomeres 1–4 without setae, podomere 5 with 1 lateral seta, podomere 6 with 2 lateral setae, podomere 7 proximally with 1 posterior seta (Fig. 5D, E). Apical podomere (7) elongated, forming 3 branches, 1 short and pointed (spinous) posterior branch, and 2 long anterior branches, both proximally thin cylindrical, distally flattened (laminate) and paddle-shaped, almost triangular with sinuate margin. The 2 long branches rest in the sheath formed by anterior gonopod (Fig. 5F). — Female sexual characters: Female gonopores inconspicuous, behind 2^nd coxa.

A fungus in amphoromorph state was located on the 4^th antennomere (left) of the male holotype (Fig. 6).

Figure 6. 

Fungus in amphoromorph stage on antennomere 4 of the male holotype (MNHNC 8387) of Notorhinus floresi sp. nov.

1♀ (MNHNC 8390); CHILE: Biobío, El Natri, Lanalhue, Contulmo; 37.9°S 73.27°W; 23.iv.2020; Edgardo Flores leg. (e27).

Body elongate and thread-like, pale white (Fig. 7), 11.5 mm long, 0.37 mm wide, br80+T. Head pyriform (Fig. 8A) with incised labrum (Fig. 8B) and antennae elbowed between antennomere 4 and 5 (Fig. 8C). Sensilla basiconica on antennomere 5 absent, sensilla basiconica on antennomere 6 arranged in oval field (Fig. 8C), 6 spiniform sensilla basiconica on antennomere 7 arranged in single row (Fig. 8D) (2 rows in N. floresi sp. nov.). Lateral metazonal sculpturing present (Fig. 8F). Two backwards projecting spines behind the ozopores and 3 setae between spines (Fig. 8G) as present in N. floresi sp. nov. Fluke-shaped projections on the posterior margin of metazonites (limbus) (Fig. 8H) as in N. floresi sp. nov. Because only a single female specimen of Notorhinus sp. (MNHNC 8390) is known, we refrain from describing it as a new species until male specimens are available.

Figure 7. 

Notorhinus sp., female (MNHNC 8390). A Habitus, lateral view. B Head and anterior body, lateral view.

Figure 8. 

Notorhinus sp., female (MNHNC 8390), SEM. A Head and anterior body-rings, frontal view. B Apical parts of gnathochilarium and labrum, ventral view. C Left antenna, lateral view. D Antennomere 7 with apical sensory structures. E Tarsal claw of mid-body leg. F Mid-body tergite, dorsal view. G Ozopore, lateral view, arrows indicate spines behind ozopore. H Posterior tergal margin (limbus), dorsal view, arrow indicates fluke-shaped sculpture. I Posterior body-rings and telson, ventral view. Abbreviations: I–VII = antennomeres, ac = apical cone, cl = tarsal claw, co = collum, ep = epicranium, fh = forehead, gn = gnathochilarium, hp = hypoproct, L1 = leg-pair 1, L2 = leg-pair 2, la = labrum, LL = lamella lingualis, md = mandible gnathal lobe, me = mentum, mz = metazonite, oz = ozopore, pp = paraproct, pr = preanal ring, pz = prozonite, sb = sensilla basiconica, ssb = spiniform sensilla basiconica, sti = gnathochilarial stipes, ta = tarsus.