Taxonomy, Volume 6, Issue 3 (September 2026) – 13 articles

A field inventory in the Rio Chapecó drainage, southern Brazil, about 11,120 km², revealed an unexpected diversity of endemic small fossorial catfishes, genus Cambeva, comprising 2 species recently described and 11 undescribed. They were found in different habitats, including sediment types and altitudes, and exhibited great morphological diversity, suggesting them to be a species flock. The objectives of this study were to analyse criteria (monophyly, endemicity, species richness, ecomorphological diversity) used to recognise species flocks and to describe the new species, which were diagnosed using external morphology and osteological characters. The phylogenetic analyses using COI, CYTB and RAG2 (2305 bp) for 64 species of Cambeva and 4 outgroups did not support that species assemblage as a single monophyletic group but supported a clade with 3 species, the C. alphabelardense clade, and a clade with 10 species, the C. betabelardense clade. The latter clade was recognised as a putative species flock based on those criteria. A time-calibrated analysis indicated the origin and diversification of both clades during the Miocene, a timeframe coinciding with the emergence and persistence of the Paranean Sea, which may have isolated adjacent river drainages, favouring the high species diversification of Cambeva, besides diversification of the Crenicichla missioneira complex from the same region. Full article

Compsemys is an enigmatic turtle first described over 160 years ago. Its taxonomic position has been uncertain, as many of the species placed in the genus have since been removed from it. For the last 30+ years, Compsemys victa has been the only recognized North American fossil species. New fossil specimens collected from the Paleocene in the United States necessitate a re-evaluation of the taxonomy of these turtles and call into question the long-held belief that only one species of Compsemys is valid in North America. Specimens from the Paleocene are far more complete than the holotype of C. victa, and all have been referred to this species based on a similar surface texture. Differences between material from the Cretaceous and Paleocene suggest multiple species of Compsemys are valid. In addition to the genotypic species Compsemys victa, C. puercensis, and C. torrejonensis are both valid species from the Paleocene. Beyond surface sculpturing and texture, features of the carapace and plastron can be used to help differentiate the three species. North American Compsemys survived the Cretaceous–Paleogene mass extinction. Rather than being a monospecific genus, Compsemys diversified in the Paleocene. Not only does this suggest an increase in the diversity of North American compsemydids, but it also leads to the possibility of asymmetric or budding cladogenesis among Compsemys species during the Late Cretaceous and Paleocene, at least in the American Southwest. Full article

Penicillium and Talaromyces are among the most diverse genera of filamentous fungi and play important ecological roles in soil ecosystems. Despite their ecological and biotechnological relevance, the diversity of these genera remains insufficiently documented in many tropical regions of Mexico. This study aimed to identify species of Penicillium and Talaromyces isolated from soils in Veracruz, Mexico, using an integrative taxonomic approach and to evaluate selected functional traits associated with their biotechnological potential. Species identification was achieved through an integrative framework combining morphology and multilocus phylogenetic analyses. Functional characterization included qualitative assessments of laccase, manganese peroxidase, lignin peroxidase, cellulolytic activity, and phosphate-solubilizing capacity. Seven species were identified, all of which are reported here for the first time from Mexico: Penicillium citreosulfuratum, P. citrinum, P. crustosum, P. mallochii, P. shanghaiense, Talaromyces albobiverticillius, and T. aculeatus. Several isolates exhibited ligninolytic, cellulolytic, and phosphate-solubilizing activities, indicating their potential roles in organic matter decomposition, nutrient cycling, and sustainable agricultural applications. These findings expand the known distribution of Penicillium and Talaromyces in Mexico, contribute to the documentation of the country’s fungal diversity, and demonstrate the value of integrative taxonomy for revealing previously unrecorded fungal taxa in tropical soil ecosystems. Full article

Troglonectes is an endemic cavefish genus of Nemacheilidae, mainly distributed in Guangxi and Guizhou, China. In April 2025, ten specimens of Troglonectes were collected from a subterranean stream of a Liujiang River tributary in Jinchengjiang District, Hechi City, Guangxi. Based on morphological comparisons and molecular phylogenetic analyses using mitochondrial Cyt b and COI genes, these specimens were identified as two new species, namely Troglonectes bottazzii sp. nov. and Troglonectes chenlixini sp. nov. Troglonectes bottazzii sp. nov. can be distinguished from congeners by having scales posterior to the dorsal fin origin, 9–10 branched dorsal fin rays, 12–13 branched pectoral fin rays, and 14 branched caudal fin rays. Troglonectes chenlixini sp. nov. is characterized by 12 branched caudal fin rays. Phylogenetically, the two new species form reciprocally monophyletic lineages with strong support, and their genetic distances meet the interspecific divergence level of Nemacheilidae. The two new species live in sympatry in the same cave waterbody, which is rare among cave loaches. Their stable morphological differences imply niche differentiation in their microhabitat and feeding ecology, which may reduce interspecific competition and likely contributes to reproductive isolation. This discovery enriches the diversity of Troglonectes and represents a valuable case and promising system for future investigations of sympatric distribution and adaptive evolution of cave-dwelling fishes. Full article

Paragryllina currently comprises more than 30 species of predominantly dendrophilous crickets, all previously recorded exclusively from tropical rainforests environments. Over the past three decades, the taxonomy of this subtribe has undergone successive reevaluations, highlighting the need for additional taxonomic studies to improve the understanding of its diversity and distribution patterns. Herein, we describe a new genus and two new species of Paragryllina collected at cave entrances in the Brazilian states of Bahia and Minas Gerais: Grunagryllus aquaeclarae gen. et sp. nov. and G. sanctijosephi gen. et sp. nov. Grunagryllus aquaeclarae gen. et sp. nov. constitutes the first record of the subtribe from the Caatinga, a semi-arid biome endemic to Brazil, considerably expanding the known ecological and biogeographic range of Paragryllina. Both species were recorded in environments currently subjected to multiple anthropogenic threats, particularly mining activities and deforestation. The discovery and description of these taxa contribute substantially to the knowledge of Brazilian Orthoptera diversity and reinforce the importance of subterranean and ecotonal habitats as refuges of poorly known biodiversity. Full article

The Macaronesian archipelagos harbor a highly endemic fauna of the flatid genus Cyphopterum Melichar, 1905, characterized by pronounced insular diversification. Despite approximately 80% of its species being unique to the region, the morphology and biology of their immature stages remain virtually unknown. This lack of ontogenetic data has long hindered more thorough studies on these planthoppers. To address this gap, the present study provides the first comprehensive description of all five nymphal instars of Cyphopterum retusum (Walker, 1851) and C. fauveli Noualhier, 1897 from the Madeira archipelago. Nymphs were reared under controlled laboratory conditions to analyze developmental duration, survival rates, and morphological features. Our results demonstrate that nymphal morphology offers robust diagnostic characters. Specifically, body size, species-specific coloration, and integumentary textures distinguish the two species, whereas body size combined with the number of metatibial spines and tarsomeres and the number and arrangement of sensory pits, allow for reliable instar determination. These findings fill a significant gap in the knowledge of the family Flatidae and provide essential tools for the conservation and monitoring of these endemic lineages in vulnerable Macaronesian ecosystems. Full article

Gymnodiptychus Herzenstein, 1892, a genus of the subfamily Schizopygopsinae, currently comprises three valid species: Gymnodiptychus dybowskii, Gymnodiptychus pachycheilus, and Gymnodiptychus integrigymnatus. Previous molecular phylogenetic studies have suggested that the genus is not monophyletic, but the taxonomic status of Gymnodiptychus integrigymnatus has not been comprehensively reassessed. In this study, we conducted an integrative taxonomic investigation of Gymnodiptychus based on mitochondrial genome data, combined with morphological and osteological evidence. Phylogenetic analyses using the concatenated sequences of 13 mitochondrial protein-coding genes and two ribosomal RNA genes recovered Gymnodiptychus as non-monophyletic. Gymnodiptychus dybowskii and Gymnodiptychus pachycheilus formed a monophyletic clade sister to Diptychus, whereas Gymnodiptychus integrigymnatus formed an independent lineage sister to Schizopygopsis. Genetic distance analyses further revealed substantial divergence between Gymnodiptychus integrigymnatus and other members of Gymnodiptychus. Morphological and osteological comparisons demonstrated that Gymnodiptychus integrigymnatus differs markedly from the other two species, Gymnodiptychus dybowskii and Gymnodiptychus pachycheilus, in lacking pectoral girdle scales, possessing extremely reduced maxillary barbels, having a terminal mouth, and lacking the supraorbital bone. Based on this combined evidence, we establish the new genus Gaoligongia gen. nov. for Gymnodiptychus integrigymnatus Mo, 1989, which is herein reassigned as Gaoligongia integrigymnata (Mo, 1989), comb. nov. We also provide a revised diagnosis of Gymnodiptychus and a key to the genera of Schizopygopsinae. Full article

This study presents a cytogenetic and comparative analysis of three rare terrestrial orchid species from Thailand: Habenaria janellehayneana, H. rhodocheila, and Nervilia khaoyaica. Somatic chromosome numbers, karyotype structures, and chromosomal morphology were investigated using conventional cytological techniques. The results revealed that both H. janellehayneana and H. rhodocheila possess a chromosome number of 2n = 42 with a fundamental number (NF) of 84, whereas N. khaoyaica has 2n = 36 and NF = 72. Karyotype formulas were determined as 11m + 10sm for H. janellehayneana, 21m for H. rhodocheila, and 2m + 16sm for N. khaoyaica, all indicating symmetrical karyotypes. Multivariate analyses, including Principal Component Analysis (PCA) and hierarchical clustering, were applied to both morphological and karyological datasets. The results demonstrated clear separation between genera along the primary component axis, while species within Habenaria were distinguished along the secondary axis. Karyotype-based PCA further supported distinct chromosomal patterns among all three species, despite identical chromosome numbers in the two Habenaria taxa. This study provides the first cytogenetic report for these species and highlights the importance of chromosome structure, particularly centromere position and arm ratio, in species delimitation. The findings contribute valuable baseline data for taxonomy, evolutionary studies, and conservation of Orchidaceae in Thailand. Full article

Macroevolutionary analysis evaluating structural monophyly as descent with modification allows recasting of taxa in terms of physics as evolutionary mechanics. There are four natural ranks, as generalized taxa: the species, genus, lineage, and metalineage, each with distinctive evolutionary processes. The species is the smallest group of organisms whose traits exclude two-sigma of uncertainty and otherwise are active in processes at the genus level. The genus is a complex engine using the Rule of Four and the Pareto Fractal Dimension to fashion and control changes over time in minimally monophyletic groups. Immediate descendant species are limited to four per genus. The lineage is modeled as a caulogram, a stem-taxon tree of present-day species and genera arranged in a timelike sequence. The metalineage is an informationally structured n-tuple set of caulograms for one lineage as calculated at successive times in the past following a morphological clock. Metalineages reveal sustained similar numbers of species across ca. 100 million years, or four or five ticks of a Nemesis extinction clock. Force values associated with evolutionary processes are calculated and compared for two bryophyte lineages at species, genus, and lineage levels. These comparisons include Efficiency Ratio and Evolutionary Force, as well as analogues of classical mechanics: evolutionary distance, velocity, acceleration, force, work, and kinetic energy. A geometric explanation is offered for the Rule of Four constraining the size of minimally monophyletic groups. Full article

Identification keys are important aspects of taxonomic research, but their quality varies substantially. I surveyed all the keys associated with the description of new non-insect animal genera that were available to me (through online and library resources or emailed pdfs received upon request from authors) published in 2021 and 2022. I found 50 keys in 45 papers that permitted the identification of 441 genera, of which 82 were newly described. I assessed the same variables as treated in an earlier paper that dealt only with insects over the same time period. Of the 17 variables evaluated as to whether the key was as useful as possible or whether it was suboptimal, an average of 5.6 were found wanting, very similar to the average for insects (5.7). Important differences between insect and non-insect datasets are: (i) the relatively lower frequency of identification keys associated with the description of new genera in non-insects, (ii) the relatively higher level in the taxonomic hierarchy to which the keys applied in non-insects and (iii) the higher proportion of keys that were to the global fauna in non-insect papers. The frequencies of occurrence of suboptimality among the 17 variables were also similar between the two datasets. Evaluation of non-insect papers suggested several additional recommendations for authors to bear in mind when constructing a key above those resulting from a similar survey of insects. Full article

Two new species of the subfamily Lecithocerinae (Gelechioidea, Lecithoceridae); Notioseus liberianus Park & Karisch, sp. nov. and Lecithocera maruana Park & Karisch, sp. nov., are described from the Nimba Mountains, bordering Guinea and Liberia. At the same time, Dragmatucha flavoaurea Park & Karisch, 2022, is transferred to Notioseus Park, 2018, resulting in a new combination Notioseus flavoaurea (Park & Karisch, 2022), comb. nov. This species is reported for the first time from Liberia and Guinea, and the male is described and illustrated for the first time, including details of the male genitalia. In addition, Pectinimura paraliberalis Park, 2023, P. bongoensis Park, 2023, and Homaloxestis rawlinsi Park, 2018, are reported from Liberia for the first time. The female genitalia of P. paraliberalis are also newly described and illustrated. Full article

Two new species of Lonchaeidae in the genus Lonchaea, namely Lonchaea desirade sp. nov. and Lonchaea minutissima sp. nov., are described from the island of Guadeloupe in the Lesser Antilles, an island group in the southern Caribbean Sea. The genitalia of the new species are figured, and comparison is made with other similar species in the Neotropical fauna. Previous lonchaeid records for the Caribbean islands are reviewed. Full article

Knowledge of the biology of the genus Vitis has undergone a profound transformation, evolving from the morphological descriptions of classical ampelography to the high-resolution analyses enabled by modern phylogenomics. This review explores the “Paradox of the Vine”—the remarkable phenotypic plasticity that historically complicated botanical nomenclature—and examines how genomic tools have helped resolve many of these long-standing taxonomic challenges. We trace the development of grapevine genomics from the first near-homozygous reference genome (PN40024) to the current era of telomere-to-telomere (T2T) assemblies and phased diploid genomes. Attention is given to the genomic “dark matter” represented by transposable elements and structural variation, which contribute substantially to varietal identity and species-specific adaptation to changing environmental conditions. Advances in bioinformatic methodologies, including pangenome graph construction and machine learning-based variant detection, now enable clonal discrimination and complex parentage analysis with unprecedented precision. The definition of genuine wild grapevines (Vitis vinifera subsp. sylvestris) remains a critical issue in studies of grapevine evolution, domestication, and genome structure. The traditional concept of wild populations free from introgression by cultivated grapevines has been increasingly challenged by ecological observations and molecular evidence. Distinguishing truly wild populations from feral lineages is therefore essential for reconstructing the history of grapevine domestication and understanding patterns of gene flow between cultivated and wild compartments. Future progress in Vitis systematics will depend on the integration of genomic, ecological, and morphometric approaches. We propose that the next generation of grapevine taxonomy will combine the historical insights of ampelography with high-throughput phenotyping and comprehensive pangenomic resources, leading to a predictive and evolutionarily informed framework for the classification of Vitis species and cultivars. Full article