Formalizing Invertebrate Morphological Data: A Descriptive Model for Cuticle-Based Skeleto-Muscular Systems, an Ontology for Insect Anatomy, and their Potential Applications in Biodiversity Research and Informatics

The spectacular radiation of insects has produced a stunning diversity of phenotypes. During the past 250 years, research on insect systematics has generated hundreds of terms for naming and comparing them. In its current form, this terminological diversity is presented in natural language and lacks formalization, which prohibits computer-assisted comparison using semantic web technologies. Here we propose a Model for Describing Cuticular Anatomical Structures (MoDCAS) which incorporates structural properties and positional relationships for standardized, consistent, and reproducible descriptions of arthropod phenotypes. We applied the MoDCAS framework in creating the ontology for the Anatomy of the Insect Skeleto-Muscular system (AISM). The AISM is the first general insect ontology that aims to cover all taxa by providing generalized, fully logical, and queryable, definitions for each term. It was built using the Ontology Development Kit (ODK), which maximizes interoperability with Uberon (Uberon multispecies anatomy ontology) and other basic ontologies, enhancing the integration of insect anatomy into the broader biological sciences. A template system for adding new terms, extending, and linking the AISM to additional anatomical, phenotypic, genetic, and chemical ontologies is also introduced. The AISM is proposed as the backbone for taxon-specific insect ontologies and has potential applications spanning systematic biology and biodiversity informatics, allowing users to: 1) use controlled vocabularies and create semiautomated computer-parsable insect morphological descriptions; 2) integrate insect morphology into broader fields of research, including ontology-informed phylogenetic methods, logical homology hypothesis testing, evo-devo studies, and genotype to phenotype mapping; and 3) automate the extraction of morphological data from the literature, enabling the generation of large-scale phenomic data, by facilitating the production and testing of informatic tools able to extract, link, annotate, and process morphological data. This descriptive model and its ontological applications will allow for clear and semantically interoperable integration of arthropod phenotypes in biodiversity studies.

Revision of the Neotropical water scavenger beetle genus Novochares Girón & Short (Coleoptera, Hydrophilidae, Acidocerinae)

The water scavenger beetle genus Novochares Girón & Short, 2021 is revised using a combination of adult morphological and DNA sequence data. Thirty-eight new species are described: Novocharesaperitosp. nov. (Bolivia), N.bacasp. nov. (Brazil, Ecuador, Peru, Suriname), N.bidenssp. nov. (Brazil), N.bisinuatussp. nov. (Brazil), N.clavierisp. nov. (Brazil, French Guiana, Peru), N.dantasp. nov. (Venezuela), N.dentatussp. nov. (Ecuador, Venezuela), N.dicranospathussp. nov. (Peru), N.duosp. nov. (Brazil, French Guiana, Guyana, Suriname, Venezuela), N.fernandezaesp. nov. (Brazil, Peru, Venezuela), N.florifersp. nov. (Brazil), N.furcatussp. nov. (Brazil), N.garciaisp. nov. (Venezuela), N.garfosp. nov. (Brazil), N.geminussp. nov. (Brazil), N.kawsaysp. nov. (Ecuador, Peru), N.latussp. nov. (Brazil), N.minorsp. nov. (Peru, Suriname, Venezuela), N.mojenossp. nov. (Bolivia), N.murasp. nov. (Brazil), N.orchissp. nov. (Brazil, French Guiana, Suriname), N.pastinumsp. nov. (Ecuador), N.pertusussp. nov. (Brazil), N.piaroasp. nov. (Venezuela), N.pilatussp. nov. (Venezuela), N.pumesp. nov. (Venezuela), N.punctatostriatussp. nov. (Brazil, French Guiana, Guyana, Peru, Suriname), N.quadrispinussp. nov. (Brazil, Guyana, Suriname), N.spanglerisp. nov. (Peru), N.tambopatensesp. nov. (Peru), N.tenedorsp. nov. (Guyana, Venezuela), N.triangularissp. nov. (Bolivia, Brazil, Paraguay), N.tridentissp. nov. (Brazil), N.trifurcatussp. nov. (Peru), N.unguissp. nov. (Bolivia, Peru), N.xingusp. nov. (Brazil), and N.yanomamisp. nov. (Venezuela), N.yorasp. nov. (Peru). One new synonym is proposed: N.carmona (Short, 2005) syn. nov. was determined to be a junior subjective synonym of N.chaquensis (Fernández, 1982). Novocharesinornatus (d'Orchymont, 1926) is considered incertae sedis. Updated distributions and new records are provided for most previously described species in the genus. Novocharessallaei (Sharp, 1882) is considered native to the USA (Florida) and not an introduced species as previously suggested. Novochares now contains 52 species and spans the entire Neotropical region from Mexico to Argentina, including the Caribbean islands.

Female terminalia morphology and cladistic relations among Tok-Tok beetles (Tenebrionidae: Sepidiini)

Tok-tokkies are one of the most iconic lineages within Tenebrionidae. In addition to containing some of the largest darkling beetles, this tribe is recognized for its remarkable form of sexual communication known as substrate tapping. Nevertheless, the phylogenetic relationships within the group remain poorly understood. This study investigates the usefulness of female terminalia morphology for delimiting Sepidiini and reconstructing relationships among it. Data on the structure of the ovipositors, genital tubes and spicula ventrali have been generated for >200 species representing 28 Pimeliinae tribes. This dataset was used in a comparative analysis at the subfamilial level, which resulted in recognition of several unique features of tok-tokkie terminalia. Additionally, new features linking phenotypically challenging tribes also were recovered (Cryptochilini + Idisiini + Pimeliini). Secondly, 23 characters linked to the structure of female terminalia were defined for tok-tok beetles. Cladistic analysis demonstrates the nonmonophyletic nature of most of the recognized subtribes. The morphological dataset was analysed separately and in combination with available molecular data (CAD, Wg, cox1, cox2, 28S). All obtained topologies were largely congruent, supporting the following changes: Palpomodina Kamiński & Gearner subtr.n. is erected to accommodate the genera Namibomodes and Palpomodes; Argenticrinis and Bombocnodulus are transferred from Hypomelina to Molurina; 153 species and subspecies previously classified within Psammodes are distributed over three separate genera (Mariazofia Kamiński nom.n., Piesomera stat.r., Psammodes sens.n.). Psammodes sklodowskae Kamiński & Gearner sp.n. is described. Preliminary investigation of the ovipositor of Mariazofia basuto (Koch) comb.n. was carried out with the application of microcomputed tomography, illuminating the muscular system as a reliable reference point for recognizing homologous elements in highly modified ovipositors.

Impact of host demography and evolutionary history on endosymbiont molecular evolution: A test in carpenter ants (genus Camponotus) and their Blochmannia endosymbionts

Obligate endosymbioses are tight associations between symbionts and the hosts they live inside. Hosts and their associated obligate endosymbionts generally exhibit codiversification, which has been documented in taxonomically diverse insect lineages. Host demography (e.g., effective population sizes) may impact the demography of endosymbionts, which may lead to an association between host demography and the patterns and processes of endosymbiont molecular evolution. Here, we used whole-genome sequencing data for carpenter ants (Genus Camponotus; subgenera Camponotus and Tanaemyrmex) and their Blochmannia endosymbionts as our study system to address whether Camponotus demography shapes Blochmannia molecular evolution. Using whole-genome phylogenomics, we confirmed previous work identifying codiversification between carpenter ants and their Blochmannia endosymbionts. We found that Blochmannia genes have evolved at a pace ~30× faster than that of their hosts' molecular evolution and that these rates are positively associated with host rates of molecular evolution. Using multiple tests for selection in Blochmannia genes, we found signatures of positive selection and shifts in selection strength across the phylogeny. Host demography was associated with Blochmannia shifts toward increased selection strengths, but not associated with Blochmannia selection relaxation, positive selection, genetic drift rates, or genome size evolution. Mixed support for relationships between host effective population sizes and Blochmannia molecular evolution suggests weak or uncoupled relationships between host demography and Blochmannia population genomic processes. Finally, we found that Blochmannia genome size evolution was associated with genome-wide estimates of genetic drift and number of genes with relaxed selection pressures.

The Acidocerinae (Coleoptera, Hydrophilidae): taxonomy, classification, and catalog of species

The cosmopolitan subfamily Acidocerinae (Coleoptera: Hydrophilidae) is one of the largest and most taxonomically challenging lineages of water scavenger beetles. Recent phylogenetic studies have substantially advanced our understanding of acidocerine relationships but also illuminated the twin challenges of poorly delineated generic concepts and a classification broadly incompatible with the phylogeny. Here, these two challenges are addressed by providing a comprehensive synthesis and taxonomic tools for the Acidocerinae, including (1) a brief history and the current state of acidocerine classification, (2) a review of acidocerine ecology and collection methods, (3) the current knowledge of larval and fossil acidocerines, (4) a morphological primer on characters of taxonomic and systematic importance within the lineage, (5) a key to the world genera of Acidocerinae, (6) diagnoses, habitus, and aedeagal images, distribution maps, and summary of knowledge for each of the 23 extant genera in the subfamily, and (7) a complete annotated taxonomic catalog including the published distributions, synonyms, and references for all described 541 acidocerine species recognized as of 1 April 2021. The following nomenclatural acts are proposed to bring the phylogeny and classification into alignment: Colossochares gen. nov. is established to accommodate two African species previously described as Helochares (s. str.); Novochares gen. nov. is newly established to accommodate 15 Neotropical species previously included in Helochares (s. str.); the remaining Helochares subgenera Helocharimorphus Kuwert syn. nov. and Hydrobaticus MacLeay syn. nov. are synonymized with Helochares Mulsant. Peltochares Régimbart sensu nov. is redefined to include eight Old World species previously included in Helochares (s. str.). A lectotype is designated for Peltochares conspicuus Régimbart, the type species of the genus. The taxonomic and morphological circumscription of Helochares sensu nov. is narrowed and redefined.

Review of the Neotropical water scavenger beetle genus Tobochares Short & García, 2007 (Coleoptera, Hydrophilidae, Acidocerinae): new lineages, new species, and new records

The water scavenger beetle genus Tobochares Short & García, 2007 currently contains ten species, including one known but formally undescribed taxon. Although Tobochares was revised in 2017, ongoing fieldwork as well as an expanded concept of the genus has led to the recognition of numerous additional species. Here a combination of morphological and molecular data is presented to review this newly found Tobochares diversity. Fifteen new species are described from South America, bringing the total number of known species to 25: Tobocharesakoeriosp. nov. (Suriname), T.arawaksp. nov. (Guyana), T.anthonyaesp. nov. (Venezuela: Bolívar), T.aturessp. nov., (Venezuela: Amazonas), T.benettiisp. nov. (Brazil: Amazonas), T.canaimasp. nov. (Venezuela: Bolívar), T.communissp. nov. (Brazil: Amapá and Roraima, Guyana, Suriname, Venezuela: Bolívar), T.fusussp. nov. (Brazil: Amapá, French Guiana), T.goiassp. nov. (Brazil: Goiás), T.kappelsp. nov. (Suriname), T.kolokoesp. nov. (Suriname), T.luteomargosp. nov. (Venezuela: Bolívar), T.micropssp. nov. (Suriname), T.pemonsp. nov. (Venezuela: Bolívar), and T.romanoaesp. nov. (Brazil: Roraima). Both morphological and molecular analyses support four clades within the genus, which are here diagnosed and described as species groups. New distributional records are provided for T.kusad Kohlenberg & Short, 2017 and T.sipaliwini Short & Kadosoe, 2011, both of which are recorded from Brazil for the first time. Previously restricted to the Guiana Shield region of South America, the distributional range of the genus is now broadly expanded to include localities as far south as the central Brazilian state of Goiás. Consistent with the biology of the previously described species, almost all the new species described here are associated with seepage and wet rock habitats. Remarkably, one species, T.fusussp. nov., was collected in both seepage habitats as well as in the rotting fruits of Clusia Linnaeus (Clusiaceae), making it one of the few known acidocerines with terrestrial habits outside of the genus Quadriops Hansen, 1999. High-resolution images of most species are included, as well as a key to species groups, species, and habitat photographs.

Status of knowledge of the broad-nosed weevils of Colombia (Coleoptera, Curculionidae, Entiminae)

Broad-nosed weevils in the subfamily Entiminae (Coleoptera: Curculionidae) are highly diverse, not only in terms of number of species, but also in their sizes, forms and colours. There are eight tribes, 50 genera and 224 entimine species recorded from Colombia: seven genera and 142 species are considered endemic and only a handful of species, which are recognised as pests of Citrus or potatoes, are broadly known. The large diversity of this subfamily in the country is only superficially known and even though genus level identifications are generally achievable, species identification remains quite challenging, due in part to limited access to broadly-scattered basic information. Summaries of available information and bibliographic resources for each of the tribes represented in Colombia are offered, along with a checklist of the species of Entiminae recorded from the country, obtained from literature and a pictorial key for tribal recognition. New combinations are proposed for eight species of the genus Lanterius Alonso-Zarazaga & Lyal. Information on the distribution of entimine species in Colombia is compiled for the first time, including complete references to each original description and available taxonomic revisions. About a third of the species of Entiminae remain as recorded from the country without specific locality information. In addition, genus level distributional maps are presented, generated from data obtained from four Colombian entomological collections. Lastly, some challenges for entimine identification in Colombia, which likely extend throughout the Neotropical region, are briefly discussed. This contribution aims, in part, to facilitate and promote entimine research in northern South America.

Variability and distribution of the golden-headed weevil Compsus auricephalus (Say) (Curculionidae: Entiminae: Eustylini)

Background

The golden-headed weevil Compsus auricephalus is a native and fairly widespread species across the southern U.S.A. extending through Central America south to Panama. There are two recognised morphotypes of the species: the typical green form, with pink to cupreous head and part of the legs and the uniformly white to pale brown form. There are other Central and South American species of Compsus and related genera of similar appearance that make it challenging to provide accurate identifications of introduced species at ports of entry.

New information

Here, we re-describe the species, provide images of the habitus, miscellaneous morphological structures and male and female genitalia. We discuss the morphological variation of Compsus auricephalus across its distributional range, by revising and updating its distributional range, based on data from entomological collections in the U.S.A. and Canada. The revised distribution of C. auricephalus extends as far south as Zacapa in Guatemala. Records south from there correspond to a different species, with affinities to C. auricephalus that we discuss and illustrate. We also discuss morphological affinities and differences with other similar species. Furthermore, we summarise information regarding the biology, host plants and natural enemies of C. auricephalus.

Three additional new genera of acidocerine water scavenger beetles from the Guiana and Brazilian Shield regions of South America (Coleoptera, Hydrophilidae, Acidocerinae)

Recent study of the water scavenger beetle subfamily Acidocerinae in the Neotropical region has uncovered numerous undescribed species that are not able to be placed in existing genera. Here, we describe three new genera to accommodate 17 of these new species from South America: Aulonochares gen. nov. for Aulonochareslingulatus sp. nov. (French Guiana, Suriname), Aulonocharesnovoairensis sp. nov. (Brazil), and Aulonocharestubulus sp. nov. (Brazil, Guyana, Suriname, Venezuela); Ephydrolithus gen. nov. for Ephydrolithushamadae sp. nov. (Brazil), Ephydrolithusminor sp. nov. (Brazil), Ephydrolithusogmos sp. nov. (Brazil), Ephydrolithusspiculatus sp. nov. (Brazil), and Ephydrolithusteli sp. nov. (Brazil); and Primocerus gen. nov. for Primoceruscuspidis sp. nov. (Venezuela), Primocerusgigas sp. nov. (Venezuela), Primocerusneutrum sp. nov. (Guyana, Suriname, Venezuela), Primocerusocellatus sp. nov. (Venezuela), Primoceruspetilus sp. nov. (Brazil), Primoceruspijiguaense sp. nov. (Venezuela), Primocerusmaipure sp. nov. (Venezuela), Primocerussemipubescens sp. nov. (Guyana), and Primocerusstriatolatus sp. nov. (Suriname). The genus Ephydrolithus gen. nov. is currently known to be restricted to seepages in the mountainous regions of the Brazilian Shield. Aulonochares gen. nov. and Primocerus gen. nov. are both currently only known from the Guiana Shield, though widespread in that region where they are associated with streams and seeps. We present differential diagnoses, maps, habitat details, and illustrations of all new genera and species here described.

Three new genera of acidocerine water scavenger beetles from tropical South America (Coleoptera, Hydrophilidae, Acidocerinae)

Recent collecting efforts in the Neotropics have led to the discovery of numerous new species and lineages of aquatic beetles. Here, three new genera are described to accommodate fifteen new species of water scavenger beetles of the subfamily Acidocerinae from northern South America: Crucisternumgen. n. for C.escalerasp. n. (Venezuela), C.ouboterisp. n. (Guyana, French Guiana, Suriname, Venezuela), C.queneyisp. n. (French Guiana), C.sinuatussp. n. (Brazil), C.toboganensissp. n. (Venezuela), C.vanessaesp. n. (Suriname), and C.xingusp. n. (Brazil); Katasophistesgen. n. for K.charynaesp. n. (Peru), K.cuzcosp. n. (Peru), K.meridasp. n. (Venezuela) and K.superficialissp. n. (Ecuador); and Nanosaphesgen. n. for N.castaneussp. n. (Brazil), N.hesperussp. n. (Suriname), N.punctatussp. n. (Guyana), and N.tricolorsp. n. (Guyana, Suriname). It was also found that the monotypic Neotropical endemic genus Dieroxenus Spangler, 1979, syn. n. is congeneric with Chasmogenus Sharp, 1882 resulting in the single new combination Chasmogenuscremnobates (Spangler, 1979), comb. n.. Katasophistesmeridasp. n. is known exclusively from seepage habitats, while the remaining taxa described herein are primarily associated with the margins of densely forested streams. Diagnoses, illustrations, distribution maps, and habitat summaries are provided for all new genera and species. A key to the genera of Acidocerinae of the New World is provided.

Revision of the Neotropical water scavenger beetle genus Quadriops Hansen, 1999 (Coleoptera, Hydrophilidae, Acidocerinae)

The genus Quadriops Hansen, 1999 is revised and redescribed. The genus is found to contain six species, including two that are here described as new: Quadriops clusiasp. n. (Brazil, Guyana, Suriname) and Q. acroreiussp. n. (Suriname, French Guiana). Two species are found to be junior subjective synonyms of Q. depressus Hansen, 1999: Q. amazonensis García, 2000, syn. n. and Q. politus Hansen, 1999, syn. n. The male of Q. similaris Hansen, 1999 is described for the first time. New records are provided for Q. dentatus Hansen, 1999, Q. reticulatus Hansen, 1999, and Q. similaris. All species are described and illustrated in detail. Most species are confirmed as having a terrestrial way of life, with several species being found in rotten fruits, sap flows, and dead wood. Furthermore, we discuss ecological trends of the species given their collecting information.

Revision of the Neotropical water scavenger beetle genus <i>Globulosis</i> García, 2001 (Coleoptera: Hydrophilidae: Acidocerinae)

The Neotropical water scavenger beetle genus Globulosis García, 2001 is revised. Originally described from a single male specimen from southeastern Venezuela, the genus has since been found in localities across the Guiana Shield region and beyond, including Colombia, Suriname, Guyana, and Brazil. The genus is redescribed. Morphological characters and genetic data from the mitochondrial gene COI from ten populations across its range provide support for two distinct species, corresponding loosely to geography. The type species, G. hemisphericus García, is redescribed and newly recorded from Guyana, Suriname, and Brazil (Amazonas, Para). One new species is described, Globulosis flavus sp. n. from southwestern Venezuela (Amazonas, Bolivar). The genus is associated with lotic habitats, and typically found along the margins of small to medium sized streams. High-resolution habitus and aedeagal images and distribution maps for all species are provided.

Phylogenetic assessment of the Caribbean weevil genus Lachnopus Schoenherr (Coleoptera:Curculionidae:Entiminae)

The genus Lachnopus Schoenherr (Coleoptera : Curculionidae : Entiminae : Geonemini Gistel), with 66 species described to date, is the largest and most widespread entimine weevil genus in the Caribbean region. The monophyly and internal phylogenetic composition of Lachnopus are tested, using a cladistic analysis of 61 adult morphological characters of 31 ingroup species and five outgroup taxa representing the genera Diaprepes Schoenherr, Exophthalmus Schoenherr, Pachnaeus Schoenherr (all Eustylini), Ischionoplus Chevrolat (Geonemini) and Apodrosus Marshall (Polydrusini). The analysis produced two most parsimonious cladograms with a length of 167 steps, a consistency index of 36 and a retention index of 73. According to the strict consensus and preferred character state optimisations, the examined species of Lachnopus do not form a monophyletic entity, even though most species are placed in a major L. coffeae–L. guerinii ingroup clade, which stands in sister relationship to Ischionoplus. This major clade is constituted by at least three well-recognisable subgroups, each associated with a particular geographic range in the Caribbean region: (1) a widely distributed L. coffeae–L. lineicollis ‘grade’; (2) the Hispaniolan L. proteus–L. mercator clade; (3) and the L. hispidus–L. guerinii clade with species from Cuba, Florida and Jamaica. This study provides a sound phylogenetic basis for future revisions of Lachnopus and related geonemine genera.

Scelianoma elydimorpha, a new genus and new species of entimine weevil from southwestern Puerto Rico (Coleoptera: Curculionidae, Entiminae)

Scelianoma elydimorpha Franz & Girón, new genus and new species, an entimine weevil endemic to southwestern Puerto Rico, is described and illustrated in detail, and assigned to the tribe Eustylini (Curculionidae: Entiminae). Scelianoma is distinguished from related taxa by the following diagnostic features: shape narrowly elongate, length/width ratio 2.8-3.5; integument with densely arranged scales; pronotum without conspicuous sculpturing; male metatibia with row of 5-7 teeth, each tooth with a spine-like seta; female metatibia lacking teeth, yet with row of long, narrowly depressed setae; metatibial corbel linear; elytral humeri absent, elytra in lateral view with dorsal outline subplane, lacking cuticular projections, posterior declivity strongly angulate, slightly convex (male) to rectate (female); and wings absent. The elytra of S. elydimorpha are sexually dimorphic, attenuating in males along the posterior 5/6 yet mostly subparallel in females, and the females furthermore have two rows of erect setae along each mesal side of the declivity. Scelianoma elydimorpha is common on the southern limestone slopes of the well-preserved Guánica dry forest. The immature stages and host plants are unknown.