Zootaxa

**Taxonomic revision of the Nylanderia guatemalensis species complex (Hymenoptera: Formicidae) in the Neotropics, with implications for conservation and invasion biology**

JASON L. WILLIAMS — 2026-06-23

The ant genus Nylanderia Emery comprises 138 known species and is common across most terrestrial regions worldwide. At least 15 species have spread beyond their native ranges, some becoming ecologically and economically destructive. Subtle morphology, unresolved taxonomy, and widespread distributions make these species difficult to identify, complicating conservation efforts in biodiversity hotspots like the Galápagos Islands. Here, based on a comprehensive examination of Neotropical Nylanderia, we revise the taxonomy of the N. guatemalensis complex, recognizing seven described species: N. ambulator Williams et al.; N. coveri LaPolla & Kallal; N. docilis (Forel); N. guatemalensis (Forel); N. insularis Williams sp. nov.; N. nesiotis (Wheeler) stat. nov.; and N. silvestrii (Emery); plus an undescribed eighth, N. sp. JKW1 (singleton). Among these, we confirm two in the Galápagos: the non-native N. guatemalensis and the endemic N. nesiotis. While eight other ant species in the Galápagos are considered probable endemics, N. nesiotis is the first confirmed as such. We synonymize N. lietzi (Forel), N. steinheili (Forel), N. guatemalensis cocoensis (Forel), N. guatemalensis itinerans (Forel), and N. silvestrii kuenzleri (Forel) with N. guatemalensis, and N. guatemalensis edenensis (Linsley & Usinger) with N. nesiotis. Species boundaries are supported by combined evidence from Ultraconserved Element (UCE) phylogenomics and morphology. We provide distributions, a worker-based key, and high-resolution images of available castes to facilitate species recognition, support biodiversity monitoring, and improve detection and management of invasive Nylanderia.

**Two new species of Coecobrya Yosii (Collembola: Entomobryidae) from Yunnan, China**

YI-FAN SUN — 2026-06-23

This study describes two new species of Coecobrya Yosii, 1956 (Collembola: Entomobryidae) from the Nangunhe National Nature Reserve in Yunnan, China: Coecobrya tianfucavica sp. nov., collected from bat guano inside a cave, is distinguished by the presence of macrochaeta m2i on abdominal segment I, only three macrochaetae each on abdominal segments II and III, and a highly reduced chaetotaxy on the posterior side of the ventral tube; and Coecobrya pentatriacra sp. nov., collected from forest litter and distinguished by its orange body markings and a unique chaetotaxy pattern of five central and three lateral macrochaetae on the tergite of abdominal segment IV. Both species belong to the tenebricosa-group. Molecular phylogenetic analysis based on the mitochondrial COI gene supports the independent status of both new species. The minimum genetic distances between each of them and their closely related species exceed the reported barcoding gap threshold for known species in Entomobryidae. This study provides detailed morphological descriptions, comparative analyses with similar species, and a phylogenetic tree and K2P genetic distance analysis based on DNA barcode data, thereby contributing to a better understanding of Coecobrya diversity in southwestern China.

**Review of the subgenus Ceratopius Clément, 1927 of the genus Metopius Panzer (Hymenoptera: Ichneumonidae: Metopiinae) from Japan**

SHUNSUKE MORISHITA — 2026-06-23

Japanese species of the subgenus Ceratopius Clément of the genus Metopius Panzer are reviewed. Ten species are recognized in the Japanese fauna. The following five new species are described: M. (C.) flavofacies sp. nov.; M. (C.) iris sp. nov.; M. (C.) minimus sp. nov.; M. (C.) splendens sp. nov.; M. (C.) violaceus sp. nov. Taxonomic status of M. (C.) dissectorius pieli Uchida, 1940 is changed from a subspecies of M. (C.) citratus (Geoffroy, 1785) to a separate species. Metopius (C.) pieli is newly recorded from Japan. Metopius (C.) baibarensis Uchida, 1930, M. (C.) carinatus Tolkanitz, 1985, M. (C.) dissectorius imperfectus Uchida, 1930, M. (C.) dissectorius taiwanensis Chiu, 1962, M. (C.) dissectorius trifasciatus Uchida, 1930, and M. (C.) elegans Tolkanitz, 1985 are newly synonymised under M. (C.) fuscipennis. A key to Japanese species of this subgenus is provided.

**First description of the genus Hyalella Smith, 1874 (Crustacea, Amphipoda, Hyalellidae) for the state of Mato Grosso and the Central-Western region of Brazil**

CECILIA SILVA RIBEIRO SOBRAL — 2026-06-23

This study describes the first species of Hyalella from the state of Mato Grosso, Central-West Brazil, based on material collected from the Salobra Stream (Córrego Salobra) at Recanto Ecológico da Lagoa Azul, Bom Jardim District, Nobres, Mato Grosso. Hyalella nobrensis sp. nov. is characterized by the presence of three serrate setae of a new type with an accessory seta on the inner face of the propodus of gnathopod 1, the absence of a curved seta on the inner ramus of uropod 1, simple setae on the inner margin of maxilla 2, one plumose seta on the dactylus of gnathopods 1 and 2, and a telson apically rounded with two cuspidate setae and four lateral plumose setae. This study raises the number of described Hyalella species in Brazil to 52 and expands our understanding of Hyalella diversity in additional regions of this continental-scale country.

**A new soft coral species, Aquaumbra aranea sp. nov. (Octocorallia: Malacalcyonacea: Aquaumbridae), from Fiordland, Aotearoa (New Zealand)**

SEVERIN A. KORFHAGE — 2026-06-23

We describe Aquaumbra aranea sp. nov. Korfhage & Freiwald, a new species of soft coral discovered in Fiordland, Aotearoa (New Zealand). This new species represents an extension of this previously monotypic genus Aquaumbra Breedy, van Ofwegen & Vagas, 2012. The discovery expands the known morphological and geographic diversity of the genus and its family Aquaumbridae. Aquaumbra aranea sp. nov. is morphologically distinguished from Aquaumbra klapferi Breedy, van Ofwegen & Vargas, 2012 and the sister genera Elbeenus Alderslade, 2002 by having a distinct sclerite composition and the presence of diverse sclerites. Its characteristic spider-web-like surface reticulation further differentiates it from the previously described species. Although mtMutS does not distinguish A. aranea sp. nov. from A. klapferi, and 28S rDNA provides only limited resolution, this pattern is consistent with previous findings in Octocorallia, where commonly used markers often fail to discriminate closely related species due to low substitution rates and limited resolution. We therefore interpret the observed morphological differentiations as taxonomically significant and sufficient to justify species recognition. Our findings underscore the potential for additional biodiscovery in coastal habitats in the Southwest Pacific.

**A new stag beetle of the genus Dorcus MacLeay, 1819 from Xizang, China (Coleoptera: Lucanidae: Lucaninae)**

ZHI-HAO QI — 2026-06-23

In the present study, a new stag beetle, namely Dorcus liangi Qi, Xin & Zhong, sp. nov. from Xizang, southwestern China is described and illustrated. The new species is very similar to D. fujiii Nagai & Maeda, 2010 and D. hei Liu, Luo & Wang, 2025 but it can be clearly distinguished from the latter two based on morphological details, especially genital characters. In addition, the genetic distance of the mitochondrial COI also supports the validity of the new species.

**Redescription and phylogenetic position of the poorly known ghost shrimp species, Praedatrypaea modesta (De Man, 1905) (Decapoda: Axiidea: Callianassidae)**

QI KOU — 2026-06-23

A poorly known callianassid ghost shrimp species, Praedatrypaea modesta (De Man, 1905), is redescribed and illustrated based on new material recently collected off the south coast of Hainan Island, northern continental shelf of the South China Sea. Genetic data were obtained and compared with other six congeners. With the inclusion of this species, the monophyly of Praedatrypaea Poore, Dworschak, Robles, Mantelatto & Felder, 2019 is reevaluated. The inferred phylogenetic trees, based on two matrices (4-gene and 21-gene), both support the monophyly of this genus and its placement as sister taxon to all other genera of Callianassidae Dana, 1852.

**New species of hermit crab of the genus Paguristes (Decapoda: Paguroidea: Diogenidae) from Pacific Costa Rica, Central America**

MANUEL AYÓN-PARENTE — 2026-06-23

A new hermit crab species, Paguristes costaricaensis sp. nov., is described and illustrated in detail. This is the sixteenth species of Paguristes reported from the Eastern Pacific and the fourth species from the Pacific coast of Costa Rica. Paguristes costaricaensis sp. nov. has major morphological similarities with P. fecundus Faxon, 1893, but they can be distinguished easily by the absence of spines on the dorsal margin of the propodus and carpus of pereopod 4 in P. costaricaensis sp. nov. and armed with three and three spines, respectively, in P. fecundus. A revised key to the 16 presently known species of Paguristes of the Eastern Tropical Pacific is provided.

**COX1 gene as a promising tool for barcoding different species of Euplotes (Ciliophora: Euplotidae)**

MIKHAIL M. TRIBUN — 2026-06-23

Euplotes Ehrenberg, 1830 is a highly diversified genus of ciliates comprising over 160 species. Their identification is problematic at both the morphological and the molecular level. Here, we used an integrative approach to describe four Euplotes species: E. vannus, E. aediculatus, E. sinicus and E. octocarinatus. We obtained 9 new sequences: 4 sequences of the nuclear small-subunit ribosomal RNA gene and 5 sequences of the mitochondrial cytochrome c oxidase 1 (COX1) gene. For two of these species (E. octocarinatus and E. sinicus) the COX1 gene sequences were obtained for the first time. The topology of phylogenetic trees based on the two marker genes was the same for most of the clades. The COX1 gene showed a good resolution at the intraspecific level. This finding indicates that the COX1 gene is a promising tool for barcoding different species of Euplotes.

Dolichogenidea glyphodes, sp. nov. (Hymenoptera: Braconidae: Microgastrinae), a parasitoid of Glyphodes caesalis (Walker) (Lepidoptera: Crambidae)

DO XUAN DAT — 2026-06-23

One new species of the genus Dolichogenidea Viereck, 1911, Dolichogenidea glyphodes Long & Dat, sp. nov., is described and fully illustrated based on series of specimens collected from gregarious cocoons of borers feeding on jackfruits, Glyphodes caesalis (Walker, 1859). The new species appears to be relatively specialized on their host species, parasitizing caterpillars of Crambidae infesting jackfruits (Artocarpus spp.)

**The first new species of Pelecotoides Laporte, 1833 (Coleoptera: Ripiphoridae) from the Greater Sunda Islands in a century**

ELLIOTT GORDON — 2026-06-23

Pelecotoides kadazandusun sp. nov., a new ripiphorid species from Malaysian Borneo, is described and illustrated. This represents the second species of Pelecotoides Laporte, 1833 documented from Borneo. We briefly discuss the Ripiphoridae Laporte, 1840 fauna of Borneo and present new records of Micropelecotoides Pic, 1910 from the island. A new combination is made for Pelecotomoides nigrolateralis var. fulvonotata Pic, 1924—Pelecotoides nigrolateralis ssp. fulvonotatus comb. nov.

**A new species of the subterranean genus Zhijinaphaenops Uéno, 2002, from a Karst Cave in Guizhou, China (Coleoptera: Carabidae: Trechini)**

XUELI FENG — 2026-06-23

A new eyeless species, Zhijinaphaenops lianhuaensis sp. nov., has been discovered within Lianhua Cave, Puding County, Anshun City, Guizhou Province. This new species was discovered in the same cave where the paratype specimens of Z. pubescens Uéno & Ran, 2002 were collected earlier. However, comparative examination reveals distinct differences between the two species with respect to pronotum morphology, male genitalia, and elytral size.