Abstract

Lamprosomatinae comprises ~250 species in 14 genera and four tribes, yet several Neotropical lineages remain poorly defined due to the absence of comprehensive morphological and molecular assessments. This study provides an integrative taxonomic reassessment of the closely related genera Dorisina, Lamprosoma, and Lychnophaes, including the description of two new species from Brazil. External and internal morphological characters of both sexes are documented with light and scanning electron microscopy, and updated biological information is presented, including host plant records, a newly documented parasitoid association, and distributional data. We also include observations on immatures and natural history traits. The first molecular dataset focused on Neotropical Lamprosomatinae is incorporated to evaluate generic limits and test the monophyly of the focal taxa. Our analyses reveal new insights into tribal-level relationships within Cryptocephalinae, supporting Fulcidacini + Pachybrachini and Clytrini + Cryptocephalini, while Mylassini forms a polytomy with the remaining groups. The monophyly of Lychnophaes could not be confirmed, as it is represented only by Lychnophaes imbirucu sp. nov. Conversely, Lamprosoma is recovered as monophyletic, with Lamprosoma cambuci sp. nov. clustering with two additional unidentified congeners. These results corroborate the relationships proposed by Chamorro and Konstantinov based on morphological data and reinforce the synapomorphies established for the tribe.

Chrysomeloidea, Camptosomata, Lamprosomatini, Neotropical Region, Brazil, Phylogenetic insights

The Lamprosomatinae comprise approximately 250 species across 14 genera and four tribes: Cachiporrini Chamorro & Konstantinov, 2011, Lamprosomatini Lacordaire, 1848, Neochlamysini Monrós, 1958, and Sphaerocharini Clavareau, 1913 (Chamorro 2014). Cachiporrini and Sphaerocharini each include only one genus from Brazil, while Neochlamysini contains two genera from the Afrotropical region.

Lamprosomatini is the most diverse tribe, with ten genera: Oomorphoides Monrós, 1956, distributed in the Indomalayan and Australasian regions; Lamprosoma Kirby 1818, Dorisina Monrós, 1956, Lamprosomatoides Monrós, 1958, Lychnophaes Lacordaire, 1848, and Oyarzuna Bechyné, 1950, endemic to the Neotropical region; Asisia Bezděk, Löbl & Konstantinov, 2010, and Scrophoomorphus Medvedev, 1968, endemic to the Indomalayan region; Xenoomorphus Monrós, 1956, restricted to the Afrotropical region; and Oomorphus Curtis, 1831, the only genus distributed across all biogeographical regions (Chamorro 2014; Chamorro and Konstantinov 2011; Monrós 1956, 1958, 1959, 1960; Seeno and Wilcox 1982).

According to Monrós (1956), among the Neotropical genera, three are relatively closely related: Dorisina, Lamprosoma, and Lychnophaes. The first was created for Monrós in 1956, only for allocating Lamprosoma pusillus Jacoby, 1890. The author indicated that other small species found in Central America also should be transferred to Dorisina. Despite their similarities, two characters are used to distinguish these three genera. First, Lamprosoma differs from the other two genera by possessing an appendiculate tarsal claw, whereas the other two genera have simple tarsal claws. Second, Dorisina can be distinguished from Lamprosoma and Lychnophaes by the presence of a deep fovea on the external ocular margin. Beyond these distinctions, no internal characters have been identified to further clarify the boundaries between these closely related genera, primarily due to the lack of comprehensive taxonomic revisions focused on Lamprosomatinae. Furthermore, morphology or molecular data have yet to be employed to test the monophyly of Lamprosoma, the genus that names the subfamily and comprises more than half of its species, or to elucidate the relationships among Neotropical genera.

In 2011, Chamorro and Konstantinov carried out the first phylogenetic analysis focused on Lamprosomatinae, based on morphological characters. Their study included 12 of the 14 recognized genera of the subfamily (Oyarzuna Bechyné, 1950 and Scrophoomorphus Medvedev, 1968 were not included), representing all four tribes. The main results supported the monophyly of Cryptocephalinae, with Fulcidacini and Clytrini as its tribes, and recognized Sphaerocharini as a distinct tribe within Lamprosomatinae. Five equally parsimonious trees and the consensus tree recovered Lychnophaes as the sister-group of (Dorisina + Lamprosoma), with the latter clade supported by homologous synapomorphies

Therefore, the present study aims to address open gaps in the systematics of Lamprosomatinae by describing new Brazilian species of Lamprosoma and Lychnophaes and providing detailed external and internal morphological descriptions, light microscopy and scanning electron microscopy images of both females and males, updated biological data, including records of host plants and associated parasitoids, and distribution maps. Additionally, this is the first study to incorporate molecular data to investigate the relationships among closely related Neotropical genera in the subfamily.

For this study, specimens of Lamprosoma and Lychnophaes were collected in Paraná (Curitiba) and Minas Gerais (Aiuruoca) states. Addition material, deposited in the Padre Jesus Santiago Moure Collection, Universidade Federal do Paraná was examined: Lamprosoma alacre Caxambú & Almeida, 2003, Lamprosoma azureum Germar, 1824, Lamprosoma auricaudatum Monrós, 1956, Lamprosoma amethystinum Perty, 1832, Lamprosoma bicolor Kirby, 1818, Lamprosoma chamaeleon Lacordaire, 1848, Lamprosoma chrysopygium Germar, 1824, Lamprosoma corruscum Guérin-Méneville, 1844, Lamprosoma festivum Germar, 1824, Lamprosoma podtiaguini Monrós, 1947, Lamprosoma oblongum Lacordaire, 1848, Lamprosoma seraphicum Lacordaire, 1848, and Lamprosoma triste Guérin-Méneville, 1844 (see Table S1).

The pinned material is borrowed from the museums/collections listed below (curators between parentheses): CEIOC – Coleção Entomológica do Instituto Oswaldo Cruz, Rio de Janeiro, Brazil (Márcio Felix, Claudia L. Rodrigues). CEMT – Coleção Entomológica de Mato Grosso Eurides Furtado, Universidade Federal de Mato Grosso, Cuiabá, Brazil (Fernando Z. Vaz-de-Mello). DZUP – Coleção Entomológica Padre Jesus Santiago Moure, Universidade Federal do Paraná, Curitiba, Brazil (Lúcia Massutti de Almeida). INPA – Instituto Nacional de Pesquisas da Amazônia.

Larvae and adults of a new species of Lamprosoma were hand-collected at Sítio Anagi Cambuci, Aiuruoca, Minas Gerais, Brazil. The collection site encompasses agroforestry systems and areas adjacent to the Atlantic Forest. All specimens were observed feeding on Campomanesia phaea (O. Berg) Landrum (Myrtaceae Juss.), a plant native to the Atlantic Rainforest phytogeographic domain, in the Ombrophilous Forest (Rainforest) vegetation type and geographically distributed in south-eastern Brazil, in the states of Minas Gerais, Rio de Janeiro, and São Paulo, commonly known as “cambuci”. Adults of a new species of Lychnophaes were hand-collected in Pseudobombax grandiflorum (Cav.) A. Robyns (Malvaceae Juss.), in the Centro Politécnico campus, Universidade Federal do Paraná, Curitiba, Brazil.

Both new species were studied in the Laboratório de Semioquímicos (Universidade Federal do Paraná, Curitiba) for preliminary pheromone analysis. Due to the size and availability challenges associated with the host plant C. phaea, adults of the new Lamprosoma were lab-reared on Eugenia uniflora L. (Myrtaceae), a species widely distributed in South America: northeast (Sergipe, Alagoas, and Bahia), the entire southeast and south, and the center-west (Mato Grosso do Sul) and commonly known as “pitanga”. In contrast, the new Lychnophaes collected from Pseudobombax grandiflorum (Cav.) A. Robyns was lab-reared on its original host. Despite the large size of the tree, apical portions of leafy branches could be detached and offered in the laboratory.

Following the pheromone studies and their natural death, adults were processed for morphological examination. Specimens were dissected using forceps and stylets, with one entire body of a female and male of each new species initially boiled in distilled water and soap to soften tissues. Specific structures, such as genitalia, were further treated in 10% potassium hydroxide (KOH) to remove residual tissues posteriorly stored in a microtube with glycerin. The terminology used for the adult external morphology follows Monrós (1956) and Caxambú and Almeida (1999). Suzuki (1988) was used for sclerite interpretation.

Light microscopy photos of the external morphology were taken using a Leica M205A stereomicroscope equipped with a Leica DMC4500 digital camera, using LAS software (version 3.8), at the Coleção de Invertebrados, INPA. Images of the internal morphology of adults and external morphology of the immatures were captured using a Leica MZ16 stereomicroscope, a Leica DFC500 camera, the Leica LAS 3D viewer, and the LAS Montage Module version 4.7 software (Taxonline – UFPR). Scanning electron microscope (SEM) images were obtained at the Centro de Microscopia Eletrônica of the Universidade Federal do Paraná (CEM – UFPR). Image editing was performed with specialized software. Photographs of the parasitoid wasp were taken using a Leica DFC295 camera attached to a Leica M125 stereomicroscope and stacked using Helicon Focus software (version 8.2.0) at the Laboratório de Biologia Comparada de Hymenoptera – UFPR.

Geographic distribution that has already been published (Caxambú and Almeida 1999, 2003; Lacordaire 1848; Monrós 1948a, b, 1949, 1956, 1958, 1959, 1960) and new records are presented (see Table S1). Biogeographical regionalization follows Morrone et al. (2022). Distribution maps were prepared from locality data on specimen labels and in the literature. Geographical coordinates were obtained from Google Earth Pro 7.1, and the map was generated with SimpleMappr (Shorthouse 2010) and edited in Photoshop CS2.

Records of host plants were obtained from specimen labels and the literature. Current nomenclature of host plants was verified using Flora e Funga do Brasil, the Catalogue of Life, and the USDA PLANTS Database.

For the data of the series-type material examined, the labels were copied verbatim, and semicolons (;) separate different labels, backslashes (|) separate different lines on the same label, and text within square brackets [ ] is ours.

Our data matrix comprises 19 terminal taxa, including two newly sequenced in this study and 17 previously available in GenBank. Nine species of Lamprosomatinae (Lamprosomatini) were designated as the internal group, while eight species of Cryptocephalinae (Clytrini, Cryptocephalini, Fulcidacini, Mylassini, and Pachybrachini tribes) and two species of Eumolpinae (Eumolpini) were assigned to the outgroup (see Table S2). All 19 species belong to the Eumolpinae clade (Gómez-Zurita et al. 2007; Nie et al. 2020).

Lamprosoma cambuci sp. nov. was found feeding on Campomanesia phaea (Myrtaceae), Sítio Anagi Cambuci, Aiuruoca, Minas Gerais, Brazil, while Lychnophaes imbirucu sp. nov. adults were collected on Pseudobombax grandiflorum (Cav.) A. Robyns (Malvaceae Juss.), Campus Centro Politécnico, Universidade Federal do Paraná, Curitiba, Brazil (Fig. 11). Both immature and adults cause damage to the branches (Fig. 12a), leading to branch death due to complete consumption and strangles the branch, preventing the passage of phloem.

Figure 12. 

Biological observations of Lamprosoma cambuci Santos, Jorge & Zarbin sp. nov. A Damage caused by larvae into Campomanesia phaea (O. Berg) Landrum (Myrtaceae); B adult consuming Eugenia uniflora L. (Myrtaceae); C different sizes of cases made by the larvae; D larvae of an unknown instar; E case adjacent to the damage to the host plant; F case showing the exit hole created by the Brasema sp.; G adults copulating; H different pairs of adults forming and copulating; I female laying an egg; J–L eggs.

The distribution of La. cambuci sp. nov. corresponds to the region with the greatest representation for the genus to date, since the literature only deals with studies with restricted distribution, such as Central America (Jacoby 1880) and Argentina and the Brazilian Atlantic Forest (Monrós 1948a, b) (Fig. 11). However, Ly. imbirucu sp. nov. is distributed outside the Amazonian domain, unlike the other species of the genus.

Due to difficulties in obtaining C. phaea seedlings, another Myrtaceae species, Eugenia uniflora L., was brought to the laboratory to provide food for the emerged males and females of Lamprosoma cambuci. Heavy feeding by the adults was observed (Fig. 12B), despite E. uniflora not being their native host plant. This alternative host plant was offered for two reasons: first, C. phaea was unavailable, and secondly, to prevent adult starvation. Additionally, E. uniflora was not chosen randomly; in previous years, another Lamprosomatini species was observed feeding on this tree. Therefore, we aimed to provide them with a plant previously consumed by a related species within the same tribe.

Concerning the immature stages, no description is provided here because although several cocoons of various sizes were examined, the majority were already in advanced larval stages, likely pupae, and several adults emerged during transit from the field to the laboratory. Only one larva of undetermined instar remained (Fig. 12D), but due to the absence of its host plant, it died a few days after arriving at the laboratory. This suggests that while the adult is capable of feeding on an alternative host plant, the larva does not share the same ability.

However, in literature, one can find some observations of immatures. According to Monrós (1949), for example, the larvae stay all day in a given portion of the tree, but at sunset they start their forage if the day was sunny, but if it was a rainy day, the larvae stay quiet, and do not forage. In the material we received, it was observed that foraging occurs very close to where the larvae stay during the day (Fig. 12A, E), with intense feeding along the entire branch and no evidence of competition with other larvae, as they maintain a certain distance from each other on the infested plant.

After the pupal stage, all emerged adults fed on E. uniflora L. (a single individual did not emerge, originating from the cocoon where a parasitoid emerged, Fig. 14 A–F) (Fig. 12B), with intense foraging observed among both females and males (Fig. 12B). Initially, adults were kept isolated for pheromone studies, but after this period, they were placed in rearing boxes for copulation observation. All males attempted to mate with the available females (Fig. 12G), and it was observed that copulation was preceded by several attempts until the final insertion of the aedeagus and the prolonged presence of the male on top of the female (Fig. 12H). This was followed by prolonged male presence on top of the female (Fig. 12H). Although males remained mounted after copulation, this behavior did not prevent other males from approaching or even attempting to dislodge the mounted male to mate with the same female. A few days after copulation, some females were observed laying eggs (Fig. 12I), both in the area between nodes and near the lateral buds (Fig. 12J–L).

Figure 13. 

Biological observations of Lychnophaes imbirucu sp. nov. Jorge, Santos & Zarbin: A Eggs, damage caused by an adult of Ly. imbirucu to Pseudobombax grandiflorum (Cav.) E. Robyns; B, C freshly laid eggs; C mature eggs; D case with rupture after the emergence of the adult; E adults copulating, including the female specimen of variant coloration; F female laying an egg; G, H larval case; G lateral view; I dorsal view.

Figure 14. 

Female of Brasema sp. (Hymenoptera: Eupelmidae). A Habitus, dorsal view; B head, frontal view; C head and mesosoma, dorsal view; D head, lateral view; E Part of mesosoma and metasoma, lateral view; F wing.

Ly. imbirucu sp. nov., in turn, was found feeding on P. grandiflorum (Myrtaceae). Both immature and adults cause damage to the branches and leaf petioles (Fig. 12A). Adults were found at the Campus Politécnico of the Universidade Federal do Paraná, Curitiba, Paraná from November to December 2023 and 2024, and then collected and taken for laboratory observations together with their host plant.

During the period of 2023, numerous series containing larvae, pupae, and adults about to emerge were collected in the field (Fig. 12A–C), while in 2024, only adults were found. During both periods, it was possible to observe copulation among all collected individuals, including between individuals showing different color patterns (Fig. 12E). However, only in the period of 2024 was the laying of eggs carried out individually (Fig. 12F) and covered with the egg case produced by the mother (Fig. 12G–I).

The two Lamprosomatinae species described here were initially collected for pheromone studies. The La. cambuci sp. nov. was collected and sent to the Laboratory of Semiochemicals because it was causing damage to an important native crop within an agroforestry system. Generally, such systems do not use any chemical control that could be harmful to species, soil, or the environment in general, and crops are typically grown in association with other plants. In turn, the Ly. imbirucu sp. nov. was collected to conduct chemical investigations focused on this subfamily, given that in the related subfamilies Cryptocephalinae and Eumolpinae, there is only one pheromone study for each and a few studies on cuticular profiles conducted for both groups (Santos et al. 2023). In these subfamilies, males have been found to be the sex responsible for emitting the aggregation pheromone (López et al. 2022; M.E. Vieira Xavier, PhD thesis, Federal University of Alagoas, 2019).

In laboratory arena conditions, males were instantly attracted to females. Accordingly, males and females were placed in separate aeration systems for volatile collection, as well as in SPME-based analytical systems, and after analyses with both methods, specific compounds were detected only in the female extracts. At that point, we consulted the literature in search of molecules that could indicate similarity and phylogenetic affinity, as well as data on host plants and other biological information that could guide us toward the species identification. It was then that we encountered a taxonomic impediment for both species. When searching for their respective names, we discovered that both species were still unknown to science, preventing the continuation of the chemical ecology work and requiring us to undertake a taxonomic study.

Thus, concomitantly with the description of both species, studies aiming to elucidate the chemical ecology of La. cambuci and Ly. imbirucu is underway and will be published soon.

There is only one parasitoid species so far recorded to use Lamprosomatinae as host, the wasp Ichneumon adsciti Westwood, 1882 (Hymenoptera, Ichneumonoidea, Ichneumonidae) (Chaboo et al. 2016). In the material examined for the present work, only one parasitoid emerged (Fig. 14), a Brasema Cameron, 1884 wasp (Hymenoptera: Chalcidoidea: Eupelmidae). Nevertheless, no Lamprosoma semaphoront emerged from the parasitized cocoon (Fig. 14), indicating successful development of the parasitoid and complete mortality of the host.

The genus Brasema is found throughout the New World and China, with 53 species (Gibson 1995). In South America, the genus has been recorded in Argentina and Brazil. In Central America, it has been recorded in Mexico. The species within this genus are considered parasitoids of eggs, larvae, and pupae of various insect orders, including Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera and Mantodea (Gibson 1995; UCD Community 2023), For Coleoptera, different Brasema species are associated with four different families: Brentidae, Buprestidae, Cleridae, and Curculionidae, plus the new record we present in this study for Chrysomelidae (Table S4).

That our single collected Brasema specimen can be described as follows: body dull to bright metallic green or bluish with some areas in mesoscutum (Fig. 14A); mesopleuron yellow, mesosoma similarly light-colored (Fig. 14A, C, E); metallic gold and part of legs bluish metallic and brown and protarsomeres whitish and brown (Fig. 14A, E). Head with setae varied in color and structure, usually whitish or translucent and sometimes lanceolate on face, but only rarely in dense band along inner and/or lower orbit (Fig. 14B–D). In frontal view head subcircular to slightly wider than high (Fig. 14B); in lateral view head flat meniscoidal to hemispherical or wedge-shaped (Fig. 14D); in dorsal view not distinctly transverse; torulos below of the middle line lower orbit (Fig. 14B); face with scrobal depression. Head with carinately margined, v-shaped scrobal depression extended about two-thirds distance to the anterior ocellus (Fig. 14C). Eye superficially bare (Fig. 14B–D) to conspicuously microsetose; inner orbits variedly convergent dorsally (Fig. 14C). Antenna with flagellum black, except, but rarely with some funicular segments light-colored (Fig. 14D); clypeus flat (Fig. 14B), and mandible tridentate.

Material examined. Female of Brasema labeled: BRASIL: Minas Gerais, Aiuruoca,| Sítio Angai Cambuci.| 28.VIII.2024| Col. Thiago Nicoliello, 2024; Brasema Cameron, 1884| (Eupelmidae)| Det. André L. Martins & Gary A. P. Gibson, 2025; Brasema sp.| CAMERON ♀| André L. Martins| Det. 6.I.2025; DZUP| 325713.

Currently, Chrysomelidae is recognized as a monophyletic family (Bocak et al. 2014; Douglas et al. 2023; Gómez-Zurita et al. 2007; Gómez-Zurita et al. 2008; Lawrence et al. 2011; McKenna et al. 2015; Nie et al. 2020) with 12 subfamilies. Despite the monophyly of the family, the internal relationships remain incompletely solved, including among the so-called Camptosomata, including Cryptocephalinae (Clytrini, Cryptocephalini, Mylassini, Fulcidacini, and Pachybrachini), and Lamprosomatinae, the last being the focus of this work.

Crowson (1955) erected Clytrinae, which included Fulcidacini (cited as Chlamisini), Clytrini, Cryptocephalini, and Lamprosomatini as a tribe. However, forty years after Crowson’s work, Reid (1995) conducted a cladistic analysis using both adult and larval characters, elevating Lamprosomatini to subfamily status, confirming the earlier indication by Monrós (1949). The other three taxa remained within Cryptocephalinae as tribes. In the Reid work, two other important hypotheses were put forward: (1) The monophyly of Eumolpinae + (Lamprosomatinae + Cryptocephalinae) and (2) the indication that Sphaerocharitinae (known as Sphaerocharini and corrected by Reid to take the genitive stems of the nouns) belongs to Lamprosomatinae.

Farrel (1998) conducted the first extensive molecular study, and despite the focus on the Phytophaga, the Lamprosomatinae were not included. Nevertheless, Farrel and Sequeira (2004) improved the previous study by adding 11 new sequences, including Sagrinae, Spilopyrinae, and Lamprosomatinae. Their results supported the monophyly of Chrysomelidae, composed of two clades, with Lamprosomatinae and Cryptocephalinae as sister-groups, and Eumolpinae as the sister to both (Farrel and Sequeira 2004).

The first study to propose Chrysomelidae as consisting of three major lineages with strong support was by Gómez-Zurita (2007, 2008). Although Lamprosomatinae and Sagrinae were absent, the authors carried out a parsimony analysis using morphological data and placed Lamprosomatinae in the “Eumolpinae clade”, as a sister-group to Cryptocephalinae. In this study, Cryptocephalinae s.l. was found to be monophyletic, though the internal relationships were not resolved. These results, with Lamprosomatinae as a sister-group to Cryptocephalinae, were later recovered by Nie et al. (2020) and Zhang et al. (2022), with the following topology: Spilopyrinae + (Cassidinae + (Eumolpinae + (Lamprosomatinae + Cryptocephalinae))). Despite these studies, the monophyly of Lamprosomatinae was only indicated by Duckett et al. (2004), using only two genera, Lamprosoma and Oomorphoides.

Focused on Cryptocephalinae, we have the largest sample with molecular data from five genes (COI, rrnS, pabp1, ef1a and LSU) carried out by Gómez-Zurita and Cardoso (2021), giving support to five tribes in the subfamily (Clytrini, Cryptocephalini, Fulcidacini, Mylassini and Pachybrachini) and Lamprosomatinae as sister-group.

Douglas et al. (2023) aimed to understand the relationships of flea beetles (Galerucinae: Alticini) and the position of Aulacothorax. Using genomic data, both Maximum Likelihood and coalescent phylogenetic analyses revealed the following topology: Synetinae as sister to Cassidinae + Eumolpinae + Lamprosomatinae + Cryptocephalinae. They also conducted an analysis of ancestral state reconstruction for characters of taxonomic interest in Galerucinae; this analysis indicated some synapomorphies between Lamprosomatinae and Cryptocephalinae, such as the presence of the kotpresse (shared with the distant Synetinae), and the absence of the tignum in females (found in Synetinae and Chrysomelinae). They noted that female characteristics like the presence or absence of tergite IX as palpi or hemitergites and ventrite IX dorsal to the vagina remain unclear as synapomorphies.

The most recent phylogenetic study, published by Kirsch et al. (2025) using genomic and transcriptomic data, obtained the same relationships as that of Douglas et al. (2023) despite their smaller taxonomic sampling.

Despite these numerous phylogenetic studies on Chrysomelidae (Douglas et al. 2023; Farrel and Sequeira 2004; Gómez-Zurita et al. 2007, 2008; Nie et al. 2020; Zhang et al. 2022; Kirsch et al. 2025), the only study specifically focusing on Lamprosomatinae was conducted by Chamorro and Konstantinov (2011), which was based exclusively on adult morphological characters. Their study included 12 of the 14 recognized genera of the subfamily, representing all four tribes, one of which then described as new. The main results supported the monophyly of Lamprosomatinae and its tribes. Five equally parsimonious trees and the consensus tree recovered the tribe Lamprosomatini, supported by four synapomorphic characters: (1) antennomeres 6 to 8 about as long as wide; (2) scutellum acutely triangular; (3) Elytral punctation arranged in regular rows or with a tendency to form such rows; and (4) stridulatory file on distal border of last abdominal ventrite (in this work we interpret this character as an elytra closing mechanism). Additionally, Lychnophaes was recovered as the sister-group of (Dorisina + Lamprosoma), supported by one synapomorphy, the posterior margin of the last abdominal ventrite convex. In the consensus tree, without unambiguous character support, Dorisina was recovered as the sister-group of Lamprosoma, with their relationship supported by a homoplasious character: sclerotized part of the spermathecal duct short, about as long as the duct of the gland.

Our analyses shed light on new relationships among the tribes of Cryptocephalinae, including Fulcidacini + Pachybrachini and Clytrini + Cryptocephalini, while Mylassini appears in a polytomy with the other groups. For the ML analysis, in addition to the relationship of Clytrini + Cryptocephalini, we verified new arrangements such as Mylassini + Pachybrachini and Fulcidacini as sister lineage of the other tribes (Fig. S1).

Lamprosomatinae was recovered as monophyletic. However, our sample includes only three genera representing the tribe Lamprosomatini (given that when we attempted to extract representatives of Sphaerocharini and other species of Lamprosomatini, the amplification of the target genes was not possible due to the age of the museum-deposited specimens and the limitations of our molecular technique, see Table S2): Lamprosoma, Lychnophaes, and Oomorphoides. Oomorphoides was confirmed as monophyletic, represented by its type species, Oomorphoides cupreatus (Baly), along with others, some of which remain unidentified at the species level. As the sister-group to Oomorphoides, we have an unidentified representative of Lamprosomatinae, possibly another member of Oomorphoides since it appears as a sister group to O. cupreatus in the ML analysis (Fig. S1) or a closely related genus. This clade, in turn, is related to Lamprosoma and Lychnophaes.

It was not possible to confirm the monophyly of Lychnophaes, which is represented only by Ly. imbirucu sp. nov. Conversely, Lamprosoma recovered as clade, with L. cambuci sp. nov. clustering alongside two additional unidentified terminals.

These results corroborate the relationships proposed by Chamorro & Konstantinov (2011) based on morphological data, further reinforcing the synapomorphies proposed for the tribe.

Lamprosoma cambuci sp. nov. and Lychnophaes imbirucu sp. nov., both described in this study, were recognized despite the absence of a comprehensive taxonomy revision for both genera. These taxonomic actions were justified by the diagnostic characters provided by Lacordaire (1848), Monrós (1948a, b, 1956), and Caxambú and Almeida (1999, 2003), which confirmed that these specimens did not correspond to any known species.

Several type specimens, deposited by Lacordaire and Germar, are currently unavailable, leading to significant taxonomic impediment and instability for the names. This situation exemplifies the challenges associated with neglected taxa, especially in a visually distinctive and diverse genus like Lamprosoma.

Given the high number of type specimens that are currently unaccounted for in European museums, we emphasize the need to reassess the taxonomy of the genus. In cases where the absence of name-bearing types prevents reliable comparison among species, the designation of neotypes may be necessary to restore nomenclatural stability. For the few species described by Monrós (1948a, b, 1956) and by Caxambú and Almeida (2003), whose type material is preserved in Brazilian and Argentine collections, we recommend a comprehensive taxonomic review. This should include detailed analyses of external and internal morphology, scanning electron microscopy, host-plant information, geographical distribution, and, whenever possible, molecular phylogenetic data. Efforts should also be directed toward integrating molecular data from unsampled lineages, including other tribes, to enhance our understanding of their evolutionary relationships.

Author contributions. Aluska Tavares dos Santos: Conceptualization, Data Curation, Investigation, Methodology, Visualization, Writing – Original Draft, Writing – Review & Editing. Isaac Reis Jorge: Investigation, Methodology, Visualization, Writing – Review & Editing. Marcos Fianco: Methodology, Analysis, Visualization, Writing – Review & Editing. Aline Sampaio: Investigation, Methodology, Visualization, Writing – Review & Editing. André Luis Martins: Investigation, Methodology, Parasitoid Identification, Visualization, Writing – Review & Editing. José Albertino Rafael: Visualization, Writing – Review & Editing. Andressa Paladini: Supervision, Visualization, Writing – Review & Editing. Paulo Henrique Gorgatti Zarbin: Supervision, Visualization, Writing – Review & Editing.

Funding. This work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico [142496/2019-7, 201147/2024-6, 465511/2014-7, 200079/2025-5, 404656/2024-2, 151844/2022-4], Fundação Araucária [162/2024 PDI], Instituto Nacional de Ciências e Tecnologia de Semioquímicos na Agricultura/Fundação de Amparo à Pesquisa do Estado de São Paulo [50871-0/2014].

Postgraduate programs involved in this study. Programa de Pós-Graduação em Química, Setor de Ciências Exatas, Universidade Federal do Paraná – UFPR, Curitiba, Brazil (ATS, PHGZ). Programa de Pós-Graduação em Entomologia, Setor de Ciências Biológicas, Universidade Federal do Paraná – UFPR, Curitiba, Brazil (ATS, IRJ, MF, AP, PHGZ). Programa de Pós-graduação em Entomologia, Instituto Nacional de Pesquisas da Amazônia – INPA, Av. André Araújo, 2936, Petrópolis, Manaus, Amazonas, Brazil (AS, JAR).

The authors would like to thank the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and the Instituto Nacional de Ciências e Tecnologia de Semioquímicos na Agricultura (INCT) for their support. AS acknowledges financial support from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, grant no. 200079/2025-5), the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Finance Code 001), and the Fundação de Amparo à Pesquisa do Estado do Amazonas (FAPEAM, Programa Posgrad). We extend our gratitude to Thiago Nicoliello for collecting and sending the material of Lamprosoma, Keli Cristiane C. Morais (Taxonline) for assistance with photography, Jennifer C. Girón Duque for providing Monrós references, and Gary A. P. Gibson for confirming the parasitoid identification. Furthermore, we would like to express our gratitude to Dr. Márcio Oliveira, curator of the Invertebrate Collection of the Instituto Nacional de Pesquisas da Amazônia (INPA) and Dra. Neusa Hamada (Laboratório de Citotaxonomia e Insetos Aquáticos – LACIA, INPA) for providing access to photographic equipment, which enabled us to capture images of the external morphology. We are grateful to Dr. Gabriel A. R. Melo (DZUP, curator of Hymenoptera) for providing the facilities needed to identify the Brasema specimen and for providing access to photographic equipment, and Dr. Mario Cupello for the language review.