Zootaxa

Otolith morphometric analysis of North Bornean Ariidae (Siluriformes): new insights and taxonomic implications

2025-07-10T10:35:00+12:00

This study examines the morphometric variation of lapilli otoliths in selected modern sea catfish species (Ariidae, Siluriformes) from northern Borneo. Given the pronounced similarity in otolith shape and anatomical features among these taxa, traditional taxonomic discrimination is often challenging, particularly at the species or genus level. To assess the taxonomic utility of otolith morphology, 216 otoliths from 12 species were analyzed using high-resolution imaging, a suite of shape indices (e.g., form factor, roundness), and precise measurements of defined ventral features (e.g., linea basalis). Seventeen morphometric parameters were subjected to various statistical analyses, including Principal Component Analysis (PCA), which delineated two major groups based on otolith shape. The rounded group comprised species from the genera Hexanematichthys, Netuma (two species), and Plicofollis (two species), while the elongated group included species from Arius (three species), Batrachocephalus, Cryptarius, Kyataphisa, and Osteogeneiosus. Subsequent statistical comparisons of selected morphological parameters revealed significant differences among some taxa. Hexanematichthys sagor exhibited a distinctly circular otolith morphology, characterized by a low aspect ratio (AR) and a uniquely oriented distal edge (AP6). Within the elongated group, although the parameters varied less, their combined assessment showed promise in differentiating certain taxa, such as Cryptarius and Osteogeneiosus, particularly through measurements of the otolith central area (R1), incisura linea basalis width (AP1), and otolith thickness ratio (R2). These findings demonstrate that even subtle morphological differences in otoliths can be quantitatively resolved to enhance taxonomic differentiation among ariid catfishes.

Asiopisinus gen. nov., a new genus of the family Theridiidae Sundevall, 1833 (Araneae, Theridiidae) from eastern Asia

2025-07-10T10:35:59+12:00

Based on morphological evidence and prior molecular phylogenetic results by Liu et al., a new genus, Asiopisinus gen. nov., is described from East Asia. The new genus comprises A. cheni sp. nov. (♂♀) as the type species, along with seven species transferred from Episinus Walckenaer, 1809: A. anfu (Liang, Liu, Yin & Yu, 2025) comb. nov., A. baoshanensis (Liu, Irfan & Peng, 2019) comb. nov., A. implicatus (Liang, Liu, Yin & Yu, 2025) comb. nov., A. nubilus (Yaginuma, 1960) comb. nov., A. ornithorhynchus (Liu, Agnarsson, Liu & Zhu, 2022) comb. nov., A. pseudonubilus (Liang, Liu, Yin & Yu, 2025) comb. nov., and A. yoshidai (Okuma, 1994) comb. nov.. The male of A. implicatus (Liang, Liu, Yin & Yu, 2025) comb. nov. is described for the first time. In addition, remarks and photos of some Chinese Episinus species are provided. The distribution records of all Asiopisinus gen. nov. species have been mapped.

Neotype designations for Hyla geographica Spix, 1824 and Hyla geographica var. sive semilineata Spix, 1824, and comments on the phylogeny, taxonomy, and diversity of the Boana semilineata species group (Anura: Hylidae)

2025-07-10T10:37:03+12:00

The uncertain identities of Hyla geographica Spix, 1824 (= Boana geographica) and Hyla geographica var. sive semilineata Spix, 1824 (= Boana semilineata) are long-standing problems in the taxonomy of the Boana semilineata species group. Several factors have contributed to this issue, such as the loss of specimens upon which both original descriptions were based, unclear identities of various synonyms, the morphological characters that vary widely and are used for diagnosis, and the scarcity of topotypical samples. Herein, we reanalyze the phylogenetic relationships among species within the B. semilineata group based on genetic data from the mitochondrial genes 16S and COI. We also report on additional topotypical material, including topotypes of most taxa under the synonymy of both B. geographica and B. semilineata. To alleviate some of the taxonomy confusion in the group, we designate neotypes for B. geographica and B. semilineata and review the taxonomy of the group.

**A new species in the Fejervarya limnocharis species complex (Amphibia: Dicroglossidae)**

2025-07-10T10:38:10+12:00

The Fejervarya limnocharis is a dicroglossid species complex distributed across east and southeast Asia, comprising four species. We previously found populations from Zhoushan Archipelago should be a distinct species with independent evolutionary history, through systematic classification based on mitochondrial DNA (mtDNA) and eight nuclear DNA loci, belonging to the fifth species in the complex. In this study, we described this new species as Fejervarya zhoushanensis sp. nov. by further comparing its genetic and morphological characteristics with its sister lineage F. kawamurai. The new species exhibited distinct genetic differences, as evidenced by genomic single nucleotide polymorphism (SNP) data. Morphological distinctions include larger snout-to-vent length (SVL), longer head length (HL), larger eye diameter (ED), greater distance between aeddistance anterior eye corners (AED), longer forearm length (FLL) and foot length (FL). Additionally, males exhibited larger tympanum diameter (TD), snout length (SL) and inner metatarsal tubercle length (IMTL); while females showed longer hindlimb length (HLL). These differences enabled clear taxonomic separation between F. zhoushanensis sp. nov. and F. kawamurai.

**Taxonomic study of Japanese species of the genus Gibberifera Obraztsov (Lepidoptera: Tortricidae: Olethreutinae), with a description of a new species**

2025-07-10T10:39:12+12:00

Gibberifera xylosmae sp. nov., whose larvae feed on Xylosma congesta (Salicaceae), is described in Japan. Photographs of adults, male and female genitalia of the three Japanese Gibberifera species are provided. The diagnosis, a key, and DNA barcodes of Japanese Gibberifera species are also presented. Intraspecific and interspecific genetic distances between Japanese Gibberifera species and other congeners are also provided.

First report of the non-marine ostracod fauna from the Lower Cretaceous Xiaonangou Formation of the Baishan Basin, NE China

2025-07-10T10:40:04+12:00

The non-marine ostracod fauna from the Xiaonangou Formation in the Baishan Basin is described in detail and illustrated for the first time. Eight samples from the Guanghuanjie-Yumuqiaozi section were analyzed, and seven taxa were identified, including Cypridea sp., Mongolocypris shai sp. nov., Lycopterocypris sinuolata, Lycopterocypris sp., Candona praevara, Candonidae gen. indet. sp. and Cyclocypris invalida. This comprehensive taxonomic study not only enhances our understanding of Cretaceous non-marine ostracods in China but also provides the first precise age constraint for the Xiaonangou Formation using ostracod biostratigraphic correlation. Based on ostracod biostratigraphic correlation, the age of the Xiaonangou Formation has been identified as early Albian. Additionally, this study supports the hypothesis of invertebrate faunal exchange in northeastern China during the Early Cretaceous.

Daphnia (Ctenodaphnia) mediterranea Alonso, 1985 (Crustacea: Cladocera) as a Mediterranean species penetrating also the Ponto-Caspian region, a rare case for the cladocerans

2025-07-10T10:40:53+12:00

The aim of this communication is to report on our discovery of a population of Daphnia (Ctenodaphnia) mediterranea Alonso, 1985 in the Kalmyk Republic representing a new record for the fauna of Russia and demonstrating the presence of this Mediterranean taxon in the Ponto-Caspian Region. Genetic information on our D. (C.) mediterranea from Kalmykia was obtained from a single specimen subjected to a complete genome study. Previously it was shown that D. (C.) mediterranea belongs to the Major Clade 2 of D. (Ctenodaphnia). Here we have demonstrated, based on two mitochondrial loci (fragments of 12S + COI genes), the existence within the latter of a remarkable Sub-clade 2, containing at least three species with very distant distribution ranges but with a similar biology: they inhabit mainly “refugial” brackish waters, and D. (C.) mediterranea belongs there. Evolution of the latter seems to be related to Paratethys basin evolution. We can hypothesize that the lowlands around Paratethys (and its subsequent remains) have provided the populations of aquatic invertebrates with numerous shallow water bodies with different salinities, including those with a high mineralization, which now represent a home of D. (C.) metiterranea.

**Discovery of the aleocharine tribe Diestotini in Japan, Ogasawara Islands, with description of a new species of the genus Diestota Mulsant & Rey (Coleoptera: Staphylinidae)**

2025-07-10T10:41:43+12:00

Diestota (Diestota) ogasawarana Hashizume & Kishimoto, sp. nov. (Coleoptera: Staphylinidae: Aleocharinae: Diestotini) is described as the first representative of the genus Diestota Mulsant & Rey, 1870, and the tribe Diestotini from Japan. Aphaenoglossa Peyerimhoff, 1937, the subgenus of Diestota, is elevated to the generic rank.

**A web of canopy discoveries part I (Araneae: Araneidae). New astonishing species of orb-weaving spiders from Ecuador and the first country record of Pozonia Schenkel, 1953**

2025-07-10T10:42:30+12:00

Two new species from the family Araneidae are described: a new species from the monotypic orb-weaving genus Spinepeira Levi, 1995, Spinepeira erwini sp. nov. (♀), and a new species of Scoloderus Simon, 1887, Scoloderus neilli sp. nov. (♀), are described from the Ecuadorian Amazon. Both species were collected with insecticidal canopy knockdown. Furthermore, herein, we present the first images of Spinepeira’s internal genitalia, and the first country record of Pozonia Schenkel, 1953 is reported with Pozonia bacillifera (Simon, 1897) collected in the canopy of Tiputini in Ecuador.

Atriadops Wandolleck, 1897 (Diptera: Nemestrinidae) recorded for the first time from Ecuador

2025-07-10T10:43:16+12:00

The genus Atriadops Wandolleck, 1897 (Diptera: Nemestrinidae) occurs in the Neotropical, Afrotropical, Indomalayan and Australasian Regions. It is easily recognized by not having ocelli and the vestigial mouthparts. Out of the seven recognized species worldwide, only one is present in the Neotropics, A. macula (Wiedemann, 1824). We report the first record of Atriadops from Ecuador, a female of A. macula, from the Napo Province, provide the first DNA barcode for the species, and discuss the possible reasons for the low number of records of this genus.