[Paleontology • 2026] Wyoteuthis linsterorum • ‘The big chunky belemnite’: A New relict megateuthidid from the Oxfordian (Late Jurassic) of Wyoming, USA, and its place in the evolutionary history of the group

 

Wyoteuthis linsterorum 

Ippolitov, Lippincott, Wahl & Lomax, 2026

 

DOI: doi.org/10.1002/spp2.70123

Abstract

We describe and discuss two finds of large and untypical belemnite rostra originating from the upper part of the Sundance Formation (Oxfordian) of Wyoming, USA. With a diameter reaching c. 60 mm at the anterior end, these rostra are the thickest known for belemnites so far. Herein they are ascribed to a new genus Wyoteuthis, comprising a single new species, W. linsterorum. Both primary and secondary morphological features (rostrum shape, alveolus position, alveolar angle, details of apical grooves and striation) allow us to justify the placement of our new taxon in the family Megateuthididae, which flourished in Toarcian to middle Jurassic time but mostly disappeared during the Bathonian, and is represented by few extremely rare and stratigraphically isolated records from younger strata. In turn, externally similar rostra previously reported in the literature from the same basin belong to Cylindroteuthididae, a common and previously only known family-level group for the Oxfordian of northwestern USA. The new genus represents a relict offshoot of the family Megateuthididae, most likely deriving from the Bajocian members of the genus Brevibelus, formerly described from North America. It demonstrates the presence of a previously unrecognized megateuthidid refugium in the north-eastern Pacific. We also discuss evolutionary macro-trends in belemnites and the possible correlations between rostrum size and soft-body size.

SYSTEMATIC PALAEONTOLOGY

Subclass COLEOIDEA Bather 1888

Order BELEMNITIDA Zittel 1895

Family MEGATEUTHIDIDAE Sachs & Nalnjaeva 1967

‘BREVIBELUS-GROUP’ sensu Ippolitov & Desai 2019

Genus Wyoteuthis nov. 

Type species: Wyoteuthis linsterorum sp. nov.

Derivation of name: A combination of ‘WYO’ (the abbreviation of the State name) and Greek τευθίς (‘squid’); together meaning ‘a squid from Wyoming’.

Differential diagnosis: It differs from Lotharingibelus Weis et al. 2025 by the much larger and more shortened rostrum, and absence of epirostrum; from Brevibelus Doyle 1992 by the same features and clear ventral displacement of the apex; from Arcobelus Sachs in Sachs & Nalnjaeva (1967) by the pronounced ventral, not dorsal displacement of the apex and less compressed cross-section, and smaller alveolar angle (29° in Wyoteuthis vs >35° in Arcobelus); from Pseudosimobelus Dzyuba & C.D. Schraer in Dzyuba et al. (2018) and from Dactyloteuthis Bayle 1878, by the absence of a single ventral groove and extremely short postalveolar part of the rostrum; from the latter additionally with a markedly less compressed rostrum. Other known members of the family Megateuthididae do not have blunt posterior ends comparable with Wyoteuthis.

Occurrence: Upper part of the Sundance Formation (Redwater Shale Member) of Wyoming, USA; late early to early middle Oxfordian (Late Jurassic).

Remarks

Systematic position: Wyoteuthis is a rare taxon with only two specimens known to date. It is stratigraphically isolated from other Megateuthididae, which are mainly restricted to the Toarcian–Bathonian interval. Explanation of its placement in that family and affinity with the genus Brevibelus is provided... 

Wyoteuthis linsterorum gen. et sp. nov., holotype, WYDICE INV-001;
upper lower to lower middle Oxfordian; upper part of Redwater Shale Member, Sundance Formation; 6 km south of Hyattville, Wyoming, USA. Collected by C. Linster.
A, dorsal view. B, right side view. C, alveolar view. D, cross-section 45 mm anterior to the presumed protoconch position. E, apical view. F, frontal CT section, view from ventral side. G, sagittal CT section, right side view. Scale bar represents: 10 mm (A–E; natural size); 30 mm (F, G).

Wyoteuthis linsterorum sp. nov.

 

Derivation of name: After the Linster Family, who discovered the holotype and donated it to the WDC, making it available for science and for the present study.

Diagnosis: Rostrum of large diameter (up to 30–32 mm at protoconch and 65–70 mm anteriorly), conical to subconical with a very short postalveolar part (Pa/DV = 0.37–0.43), posteriorly blunt with ventrally displaced mucronate apex bearing striae, grouped in unclear bunches modified as pit-like depressions. Alveolus extends into most of the length of the rostrum.

Alexey P. Ippolitov, Jessica L. Lippincott, William R. Wahl, Dean R. Lomax. 2026. ‘The big chunky belemnite’: A New relict megateuthidid from the Oxfordian (Late Jurassic) of Wyoming, USA, and its place in the evolutionary history of the group. Papers in Palaeontology. 12(5); e70123. DOI: doi.org/10.1002/spp2.70123 [09 September 2026]

[Ichthyology • 2026] Prognathodes thanatos • A New Deepwater Species of Butterflyfish (Teleostei: Chaetodontidae: Prognathodes) from Mozambique, Africa, with a Systematic Review of Chaetodontid Relationships on the Basis of Osteology

 Prognathodes thanatos

 Tea, Blum, Rocha, Parkinson & Stanley, 2026 

DOI: doi.org/10.1643/i2025038  

  x.com/IchsAndHerps

 Abstract 

Prognathodes thanatos, new species, is described on the basis of the holotype from Mozambique, Africa. The new species is readily distinguished from congeners in having the following combination of live coloration details and morphological characters: head and body silvery white with three broad, dark brown bands; pelvic fin including spine black; dorsal-fin rays XIII,19; anal-fin rays III,15; lateral line short and incomplete with 26–29 pored scales; gill rakers 4 + 12–13 = 16–17; snout length 12.6% SL; and angle of preopercle finely serrate. The new species appears to be most closely related to Prognathodes guyotensis, a poorly known, deepwater species of butterflyfish known from very few specimens. The assignment of both species to the genus Prognathodes is accompanied by a critical reassessment and discussion of the currently inadequate definition of the genus.

Prognathodes thanatos, new species, SAIAB 80277, holotype, 100.3 mm SL, off Bazaruto Archipelago, Mozambique, Africa in (A) fresh and (B) preserved coloration.
Photographs by (A) P. Heemstra, South African Institute of Aquatic Biology, copyright 2025, used with permission, and (B) C. Phan, Australian Museum Research Institute, copyright 2025.  x.com/IchsAndHerps

Underwater photographs of Prognathodes thanatos, new species, taken using remotely operated submersibles.
(A–B) 200 m, Comoro Islands; (C) depth unknown, off the coast of KwaZulu-Natal, South Africa; (D) depth unknown, likely >100 m, Leadsman Canyon, Sodwana Bay, off the coast of KwaZulu-Natal, South Africa

Yi-Kai Tea, Stanley D. Blum, Luiz A. Rocha, Kerryn Parkinson and Edward L. Stanley. 2026. A New Deepwater Species of Butterflyfish (Teleostei: Chaetodontidae: Prognathodes) from Mozambique, Africa, with a Systematic Review of Chaetodontid Relationships on the Basis of Osteology. Ichthyology & Herpetology. 114(3); 474-494. DOI: doi.org/10.1643/i2025038 (15 September 2026)  

 x.com/IchsAndHerps/status/2103540682904199366

 www.instagram.com/p/DdZv3B9E20t

[Paleontology • 2026] Dianhaia heptacantha • A non-biomineralized trilobitomorph euarthropod (Trilobitomorpha: Helmetiida: Helmetiidae) with appendicular morphology from the early Cambrian Chengjiang Biota, China

 

Dianhaia heptacantha 

Zhu, Zeng, Liu & Zhao, 2026

 DOI: doi.org/10.1017/jpa.2026.10257

Abstract

Helmetiida is a major group of Trilobitomorpha and Artiopoda known from Cambrian Burgess Shale-type Lagerstätten. Phylogenetic studies have suggested that they are closely related to trilobites as their possible sister taxon. With seven genera and eight species, Helmetiida has only been found in the Burgess Shale and the Chengjiang biota. Here we describe a new helmetiid, Dianhaia heptacantha n. gen. n. sp., from the early Cambrian Chengjiang biota (Cambrian Series 2, Stage 3), Yunnan Province, South China. Dianhaia heptacantha n. gen. n. sp. possesses an anterior sclerite that is diagnostic of Helmetiida. The semicircular cephalon bears a pair of short genal spines. The thorax consists of seven tergites, each having a pair of long pleural spines and showing edge-to-edge articulation. The pygidium carries one short terminal spine and three pairs of long lateral spines. Dianhaia heptacantha n. gen. n. sp. is distinguished from other helmetiids by different numbers of thoracic tergites and pygidial spines. Computed microtomography shows that D. heptacantha n. gen. n. sp. has a pair of antennae and 13 pairs of homonomous biramous appendages. Each biramous appendage consists of a gnathobasic protopodite, seven-podomerous endopodite, and a lobate exopodite with lamellae. Phylogenetic analysis of Artiopoda resolved Dianhaia n. gen. as the sister taxon of Haifengella within Helmetiida. The discovery of this new helmetiid enriches the taxonomic diversity and appendicular morphoanatomy of Cambrian trilobitomorphs from the Chengjiang biota.

Systematic paleontology

Euarthropoda Lankester, 1904

Artiopoda Hou and Bergström, 1997

Trilobitomorpha Størmer, 1944

Conciliterga Hou and Bergström, 1997

Helmetiida Novozhilov, 1960

Helmetiidae Simonetta and Delle Cave, 1975

Included genera: Helmetia Walcott, 1918; Kuamaia Hou, 1987; Rhombicalvaria Hou, 1987; Haifengella Zhao et al., 2014.

Dianhaia heptacantha n. gen. n. sp. from the Cambrian Stage 3 Chengjiang biota, holotype NIGP 203984, part and counterpart.
(1, 2, 4–9) Part, NIGP 203984a; (1) whole specimen; (2) interpretative drawing; (4) endopodite; (5) a thoracic biramous appendage; (6) exopodite; (7) setae on the exopodite; (8) spines on the pleural spine; (9) spines on the pygidium.
(3) Counterpart, NIGP 203984b.

Scale bars represent 5 mm (1, 2), 1 mm (3, 7), 2 mm (4–6, 8, 9).

 Abbreviations: as, anterior sclerite; ce, cephalic segment; cs, cephalic shield; cw, claw; ed, endite; en, endopodite; ex, exopodite; gs, genal spine; gn, gnathobase; hy, hypostome; lm, lamella; ls, lateral spine; ps, pleural spine; pt, protopodite; py, pygidium; sp, marginal spine; ts, terminal spine; T1–7, thoracic tergite 1–7; xs, setae on exopodite.

Dianhaia heptacantha n. gen. n. sp. from the Cambrian Stage 3 Chengjiang biota, paratype NIGP 203985.
(1) Whole specimen; (2) interpretative drawing; (3) pygidial segments; (4) cephalic and anterior thoracic segments with appendages; (5) marginal spines on the pygidial pleural spine; (6) marginal spines on the pygidium; (7) whole appendage; (8) endopodite; (9) setae on exopodite. Scale bars represent: 5 mm (1, 2), 2 mm (3), 1 mm (4–9).

Abbreviations: as, anterior sclerite; en, endopodite; ex, exopodite; ls, lateral spine; ps, pleural spine; pt, protopodite; py, pygidium; sp, marginal spine; st, sternite; ts, terminal spine; T1–7, thoracic tergite 1–7; xs, setae on exopodite.

Genus Dianhaia new genus

Etymology: Derived from Dianhai, another name of the Dian Lake, which is close to the fossil locality.

Remarks: Dianhaia n. gen. has an oval anterior sclerite and tergites with edge-to-edge articulation, supporting its assignment to Helmetiida. Its well-developed segmental boundaries and several large pygidial spines indicate that it was a member of Helmetiidae (Losso et al., 2025). Different from Helmetia and Kuamaia, Dianhaia n. gen. has long pleural spines and pygidial spines that are similar to the counterparts in Rhombicalvaria and Haifengella (Hou and Bergström, 1997; Zhao et al., 2014; Losso et al., 2025). But compared with Rhombicalvaria and Haifengella, Dianhaia n. gen. has different numbers of thoracic tergites and pygidial spines, suggesting it is a separate genus.

Dianhaia heptacantha new species

Holotype: NIGP 203984a, b, part and counterpart.

Materials: Holotype (NIGP 203984a, b); paratype (NIGP 203985).

Diagnosis: The cephalic shield possesses a pair of short genal spines. The thorax comprises seven thoracic tergites with long pleural spines. The semicircular pygidium bears one very short terminal spine and three pairs of long lateral spines. Biramous appendages have an undivided long-ovate flap with marginal setae and imbricated lamellae.

Occurrence: Maotianshan Shale Member, Yu’anshan Formation, Wutingaspis–Eoredlichia trilobite Zone, Cambrian Series 2, Stage 3, Jianshan section, Kunming City, Yunnan Province, China.

Etymology: Hepta means seven in Greek. Acantha means spine in Greek. The name derives from the seven pairs of thoracic spines and seven pygidial spines in this species.

Reconstruction of the helmetiid euarthropod Dianhaia heptacantha n. gen. n. sp. from the Cambrian Stage 3 Chengjiang biota.
 (1) Dorsal view; (2) ventral view. 
 Morphology of the articular membrane and position of antennae are inferred. The number of antennal podomeres was referred from Kuamaia lata.

 

Yuyan Zhu, Han Zeng, Yao Liu and Fangchen Zhao. 2026.  A non-biomineralized trilobitomorph euarthropod (Helmetiida) with appendicular morphology from the early Cambrian Chengjiang Biota, China. Journal of Paleontology.  First View, pp. 1 - 10. DOI: doi.org/10.1017/jpa.2026.10257 [07 October 2026]

[Invertebrate • 2026] Polycapus rubrum, Stelletta plana, ... • Four New Demosponges from Alaska and the Designation of A New Genus in Hymedesmiidae (Heteroscleromorpha, Poecilosclerida)

 

Stelletta plana sp. nov.

Polycapus rubrum gen. nov. & sp. nov.

Lehnert, Rooney & Everett, 2026

 DOI: doi.org/10.11646/zootaxa.5857.2.6 

www.fisheries.NOAA.gov 

 

Abstract

An investigation of Alaska’s extraordinarily rich sponge fauna was conducted utilizing samples retained as bycatch during National Marine Fisheries Service stock assessment bottom trawl surveys in the Gulf of Alaska and Aleutian Islands between 1997 and 2021. Subsequent analysis of the samples revealed four new species, which are representatives of four different orders of demosponges: Cladocroce cylindrica sp. nov., Julavis borealis sp. nov., Polycapus rubrum gen. nov. & sp. nov., and Stelletta plana sp. nov.. The new species are described and compared to congeners. Polycapus rubrum was assigned to the Hymedesmiidae but the combination of acanthoxeas and chelae does not occur in any other existing genus within the family which necessitates a new genus. These new collections further highlight the richness of the sponge fauna from the region.

Porifera, new species, North Pacific, Aleutian Islands, Gulf of Alaska, Tetractinellida, Axinellida, Haplosclerida, Stelletta, Polycapus, Julavis, Cladocroce, 28S

Cladocroce cylindrica, is a stalked, branching sponge distinguished by a unique spicule framework that forms a complex, web-like network. 

Julavis borealis, grows like a thin mat over organisms. Its presence in Alaska represents a massive high-latitude geographic leap for a group previously found only in warm, tropical environments. 

Cladocroce cylindrica sp. nov.  

Julavis borealis sp. nov.  

Polycapus rubrum gen. nov. & sp. nov. 

Stelletta plana sp. nov.

Helmut LEHNERT, Sean C. ROONEY and Meredith V. EVERETT. 2026. Four New Demosponges from Alaska and the Designation of A New Genus in Hymedesmiidae (Heteroscleromorpha, Poecilosclerida).  Zootaxa. 5857(2); 317-334. DOI: doi.org/10.11646/zootaxa.5857.2.6 [2026-07-29]

Nine Species of Deep-Sea Sponges Discovered in Alaska

www.fisheries.NOAA.gov/feature-story/nine-species-deep-sea-sponges-discovered-alaska

[Ichthyology • 2026] Chromis veneta • Resolving Cryptic Diversity in the Chromis viridis species complex (Blenniiformes: Pomacentridae): a multilocus phylogenetic and morphometric reassessment of species boundaries

 

Chromis veneta 

Rekha, Jayakumar, Abhilash, Ahamed Rasheeq, Saikrishnan, Vallarasu, Gladston, Chakraborty & Ajithkumar, 2026

  

DOI: doi.org/10.3389/fmars.2026.1922804

Abstract

The blue-green damselfish, Chromis viridis (Cuvier, 1830), is widely distributed across Indo-Pacific coral reefs and is among the most heavily traded marine ornamental fishes. Recent molecular studies have suggested the presence of cryptic diversity within the C. viridis complex, but species boundaries remain unresolved. Multilocus phylogenetic analyses incorporating three mitochondrial markers—cytochrome c oxidase subunit I (COI), cytochrome b (cytb), and the mitochondrial control region (D-loop)—and two nuclear markers, recombination-activating gene 1 (RAG1) and recombination-activating gene 2 (RAG2), were performed to assess lineage diversification within the Chromis viridis species complex. Specimens collected from the Lakshadweep Archipelago and the Gulf of Mannar, India, formed a distinct and well-supported lineage that was clearly separated from C. viridis sensu stricto and other congeners in phylogenetic reconstructions and genetic distance analyses. Multiple species-delimitation approaches consistently supported the recognition of this lineage as an independently evolving taxon, and morphometric analyses revealed corresponding differences in body proportions and meristic characters. Based on the concordance of molecular and morphological evidence, a new species, Chromis veneta sp. nov., is herein described from the Indian Ocean. The new species differs from C. viridis in having a relatively elongate body, narrower caudal peduncle, distinctive body pigmentation, yellowish to orangish distal fin margins, and a deeply forked caudal fin with elongate lobe tips. Additional diagnostic features include differences in dentition, gill-raker counts and sagittal otolith morphology. The discovery of C. veneta sp. nov. highlights underestimated diversity within the C. viridis complex and underscores the importance of integrative taxonomy in revealing cryptic reef-fish diversity.

Keywords: Chromis veneta sp. nov., Chromis viridis complex, cryptic species diversity, species delimitation, multilocus phylogenetics, integrative taxonomy, morphometric analysis, Pomacentridae

 

Chromis veneta sp. nov., freshly collected holotype, NBFGR/POMCVEN, 52.0 mm SL, Agatti Island.

Caption Male of Chromis veneta sp. nov. (64.51 mm SL) in live breeding coloration.

Chromis veneta sp. nov. in its natural coral reef habitat at Agatti Island, Lakshadweep, associated with branching Acropora corals and occurring sympatrically with Chromis viridis, Pomacentrus pavo, and Dascyllus aruanus.

Chromis veneta sp. nov.

 Diagnosis: Chromis veneta sp. nov. is distinguished from its congeners by the following combination of characters: dorsal-fin rays XII, 9–10 (usually 10); anal-fin rays II, 9–10 (usually 10); pectoral-fin rays 16–17 (usually 17); pelvic-fin rays I, 5; principal caudal-fin rays 8 + 7; spiniform caudal rays 3; tubed lateral-line scales 15–16; gill rakers 9–10 + 23–26 (usually 9 + 24), total 33–35 (usually 33); body depth 2.27–2.56 in SL; caudal-peduncle depth 0.63–0.77 in head length; and caudal-peduncle length 0.51–0.73 in head length. In life, the body is bright aquamarine-green with a subtle iridescent blue-green sheen. Each scale on the upper and middle flanks is narrowly edged with yellow-green, forming a fine reticulate pattern that becomes more conspicuous under illumination. The ventral surface is pale silvery white. A diffuse black patch is present at the upper base of the pectoral fin and is more conspicuous in live specimens. A fine, continuous blue-green stripe extends from the tip of the snout to the anterior margin of the orbit. Reproductively active individuals further exhibit distinct yellowish to amber pigmentation along the distal margins of the dorsal and anal fins.

Etymology: The specific epithet, veneta is derived from the Latin venetus, meaning “sea-blue” or “azure,” referring to the characteristic of blue green to turquoise coloration exhibited by the species in live condition. The name is treated as an adjective in agreement with the generic name Chromis.

 

M. U. Rekha, Teena Jayakumar T. K., Abhilash C. P. Ahamed Rasheeq A., Saikrishnan K. R., Vallarasu R., Gladston Y., Kajal Chakraborty and Ajithkumar T. T. 2026. Resolving Cryptic Diversity in the Chromis viridis species complex (Pomacentridae): a multilocus phylogenetic and morphometric reassessment of species boundaries. Front. Mar. Sci. 13; 1922804. DOI: doi.org/10.3389/fmars.2026.1922804 [04 September 2026]

[Crustacea • 2026] Pilumnus guadeloupensis • A New Species of Pilumnus Leach, 1816 (Decapoda: Brachyura) from Guadeloupe, Lesser Antilles

 

Pilumnus guadeloupensis 

Magalhães, Oliveira-Rogeri, Felder & Mantelatto, 2026

DOI: doi.org/10.5252/zoosystema2026v48a16

 Abstract  

Pilumnus Leach, 1861 is a speciose cosmopolitan genus of marine crabs typical from rocky and coral coastal environments and known to occur in tropical and temperate oceans and seas worldwide, including the waters of western Atlantic and Caribbean Sea surrounding the Lesser Antilles, a recognized hotspot of biodiversity in Caribbean. Despite recent sampling efforts, this region remains underexplored, limiting understanding of its marine fauna. To address this gap, several field expeditions have been carried out, including KARUBENTHOS 2012. This expedition extensively collected specimens of various taxonomic groups, expanding documentation of biodiversity in the Lesser Antilles. Among collections, a unique specimen of Pilumnus was recognized and analyzed through morphological and molecular approaches. Genetic analyses of this specimen, a component of molecular phylogenetic studies previously conducted by our team, confirmed its divergence from previously described species. Herein, we performed a thorough morphological examination analyzing most of the taxonomic informative characters used in species descriptions of representatives of Pilumnus. Based on the presently accessed morphological features and previously detected molecular divergence, a new species, Pilumnus guadeloupensis n. sp., is described. This species can be distinguished from others from the genus mainly by the ornamentation and tuberculation patterns of pereopods, number of anterolateral prominences and shape of the carapace. Detailed morphological comparisons with congeners, alongside a comprehensive review of the literature, are provided.

KEYWORDS: Caribbean, KARUBENTHOS 2012, morphology, Pilumnidae, new species, 

Habitus of alcohol-preserved holotype of Pilumnus guadeloupensis n. sp., male (CW = 6.44 mm),  MNHN-IU-2013-16321:
A, dorsal; B, ventral.

 Scale bar: 2 mm.

Holotype of Pilumnus guadeloupensis n. sp., male (CW = 6.44 mm),  MNHN-IU-2013-16321:
A, entire specimen on dorsal view; B, left third maxilliped, external; C, outer surface of major chela; D, left first gonopod, mesial; E, pleon and telson.

 Scale bars (mm): A, 3 mm; B, 0.7 mm; C, 2.5 mm; D, 0.2 mm; E, 1.5 mm.

Alcohol-preserved holotype of Pilumnus guadeloupensis n. sp., male (CW = 6.44 mm),  MNHN-IU-2013-16321:
A, habitus, frontal; B, carapace front, dorsal; C, left anterolateral carapace margin, dorsal; D, left suborbital and pterygostomial carapace regions, ventral; E, left third maxilliped, external; F, left (major) cheliped, dorsal; G, right (minor) chela, external; H, left (major) chela, external; I, right pereopods 4 and 5, meri, carpi, and propodi, dorsal; J, anterior sternites and pereopod coxae, ventral; K, sternopleonal cavity with pleonal lock button; L, left first gonopod, mesial. Not to scale.

Phylum ARTHROPODA Latreille, 1829

Class MALACOSTRACA Latreille, 1802

Order DECAPODA Latreille, 1802

Infraorder BRACHYURA Latreille, 1802

Family PILUMNIDAE Samouelle, 1819

Genus Pilumnus Leach, 1816

Pilumnus guadeloupensis n. sp.

 

Diagnosis. — Carapace anterodorsally with short pubescence; frontal, protogastric, and hepatic regions of dorsal surface with strong tubercules; supraorbital margins strongly toothed; anterolateral margin with four teeth, anteriormost of which formed by outer orbital tooth. Major chela palm with outer surface nearly smooth and glabrous. Ambulatory pereopods with merus dorsal margin mostly smooth, single subdistal denticle on dorsal margin of meri of pereopods 2-4; carpi and propodi with prominent spiniform tubercles.

Etymology. — The specific epithet guadeloupensis refers to Guadeloupe, the type locality of the species, and it is used here as an adjective.

 

Tatiana Magalhães, Lucas Oliveira-Rogeri, Darryl L. Felder and Fernando L. Mantelatto. 2026. A New Species of Pilumnus Leach, 1816 (Decapoda, Brachyura) from Guadeloupe, Lesser Antilles, with morphological comparisons to regional congeners. Zoosystema. 48 (16), 389-399. DOI: doi.org/10.5252/zoosystema2026v48a16 (3 July 2026)

Une nouvelle espèce de Pilumnus Leach, 1816 (Decapoda, Brachyura) de Guadeloupe, Petites Antilles, et comparaisons morphologiques avec les espèces régionales apparentées.

Pilumnus Leach, 1861 est un genre cosmopolite de crabes marins, typique des environnements côtiers rocheux et coralliens. Ces animaux sont présents dans les océans et mers tropicaux et tempérés du monde entier, notamment dans les eaux de l'Atlantique ouest et la mer des Caraïbes, y compris dans les eaux entourant les Petites Antilles, un point chaud de biodiversité en région caraïbe. Malgré de récents efforts d'échantillonnage, cette région reste sous-explorée, ce qui limite la connaissance de sa faune marine. Pour combler cette lacune, plusieurs expéditions de terrain ont été menées, dont KARUBENTHOS 2012. Cette expédition a permis de collecter de nombreux spécimens de divers groupes taxonomiques, enrichissant ainsi nos connaissances sur la biodiversité des Petites Antilles. Parmi les spécimens collectés, un spécimen unique de Pilumnus a été identifié et analysé par des approches morphologiques et moléculaires. Les analyses génétiques de ce spécimen, réalisées dans le cadre d'études de phylogénie moléculaire précédemment menées par notre équipe, ont confirmé sa divergence avec les espèces précédemment décrites. Un examen morphologique approfondi analysant la plupart des caractères taxonomiques informatifs utilisés dans les descriptions des espèces de Pilumnus a été réalisé. Sur la base des caractéristiques morphologiques décrites dans cette étude et des divergences moléculaires précédemment détectées, une nouvelle espèce, Pilumnus guadeloupensis n. sp., est décrite. Cette espèce se distingue des autres espèces du genre principalement par l'ornementation et les tubercules des péréiopodes, le nombre de proéminences antérolatérales et la forme de la carapace. Des comparaisons morphologiques détaillées avec ses congénères, ainsi qu'une revue exhaustive de la littérature, sont fournies.

Caraïbes, KARUBENTHOS 2012, morphologie, Pilumnidae, espèce nouvelle

[Crustacea • 2026] Bogidiella isajii & B. painushima • Two New Species of the Genus Bogidiella (Amphipoda: Bogidiellidae) from Japan

Bogidiella painushima 

Tomikawa, Yoshimura, Ugomeki & Shimomura, 2026 

 

DOI: doi.org/10.11646/zootaxa.5831.3.5  

 www.hiroshima-u.ac.jp

Abstract

Two new species of bogidiellid amphipods, Bogidiella isajii and B. painushima are described from an anchialine undersea cave in Minamidaito Island and freshwater flowing through a cave in Ishigaki Island, Ryukyu Islands. Bogidiella isajii sp. nov. differs from its congeners in the absence of an inner ramus on the pleopods, armature of uropods 1 and 2 rami, and shape of the telson. Bogidiella painushima sp. nov. is morphologically similar to B. aprutina and B. broodbakkeri, but differs from these two species in the shape of antennal sinus of the head, size of antenna 2 peduncular article 2 gland cone, armature of the accessory setal row of the mandible, shape of gnathopod 1 propodus and pereopod 7 coxa, and armature of the telson. Nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I from paratypes of the two new species were determined for future studies.

Crustacea, brackish, COI, freshwater, Okinawa, taxonomy

Bogidiella painushima sp. nov. 

 

KO TOMIKAWA, HIRO YOSHIMURA, MUSHI UGOMEKI and MICHITAKA SHIMOMURA. 2026. Two New Species of the Genus Bogidiella (Crustacea: Amphipoda: Bogidiellidae) from Japan.  Zootaxa. 5831(3); 399-412. DOI: doi.org/10.11646/zootaxa.5831.3.5 [2026-06-16]  

Two eyeless shrimp-like species found in Japan’s groundwater are new to science

Finding new species in unassuming settings brings light to further exploration and conservation efforts to preserve the unique diversity in groundwater environments

https://www.hiroshima-u.ac.jp/en/news/99063

https://www.eurekalert.org/news-releases/1140243

[Mollusca • 2022] Dendronotus shpataki • A New Species of the Genus Dendronotus (Gastropoda: Nudibranchia) from the Sea of Japan: a contribution of citizen science to marine zoology

  

Dendronotus shpataki sp. nov. in natural environment.

Ekimova, Mikhlina, Antokhina & Schepetov, 2022

 

DOI: doi.org/10.31610/zsr/2022.31.1.3 

  Researchgate.net/publication/358210579

Photos by Andrey Shpatak.

Abstract

 The nudibranch genus Dendronotus Alder et Hancock, 1845 is a common component of boreal and arctic ecosystems, which has recently received a considerable attention due to its high cryptic diversity. Here we describe a new species Dendronotus shpataki sp. nov. from the northwestern Sea of Japan, using the material and observations provided by Andrey Shpatak, a local citizen, diver and underwater photographer. We studied morphological features of the new species, including external morphology, coloration, jaw and radular morphology, and configuration of the reproductive system, as well as its ecological traits including possible diet preferences. We obtained DNA sequences and reconstructed the phylogeny by Bayesian Inference and Maximum Likelihood approaches using four molecular markers (mitochondrial COI and 16S rRNA, and nuclear histone H3 and 28S rRNA), and tested the boundaries between the species by calculating the uncorrected p-distances and automatic species delimitation methods ABGD and GMYC. Our results show that D. shpataki sp. nov. differs both morphologically and genetically from all other Dendronotus species. The new species possibly represents a unique example of local endemism, being found in a single locality, while other local Dendronotus species demonstrate wide distribution in the North-West Pacific. We also report on a considerable wearing of the radular teeth during feeding, which is a remarkable case for the Dendronotus.

Key words: North-West Pacific, biodiversity, morphology, radula, molecular markers, phylogeny, Nudibranchia, Dendronotidae, Dendronotus, new species

Dendronotus shpataki sp. nov., general appearance of living specimens.
 Holotype: dorsal view (A), lateral view (B) and ventral view (C).
Paratypes, dorsal view: adult specimens MIMB42309 (D), MIMB42308 (E), MIMB42305 (F)
and juvenile MIMB42306 (G). 

Scale bar: 5 mm.

Dendronotus shpataki sp. nov. in natural environment.
 Paratype MIMB42302 (A–C); the first documented finding of the new species in May 2015,
 the specimen was not collected (D); paratypes MIMB42303 (E, F).

Photos by Andrey Shpatak.

Dendronotus shpataki sp. nov.

I.A. Ekimova, A.L. Mikhlina, T.I. Antokhina and D.M. Schepetov. 2022. A Description of Dendronotus shpataki sp. nov. (Gastropoda: Nudibranchia) from the Sea of Japan: a contribution of citizen science to marine zoology. Zoosystematica Rossica. 31(1); 3–19. DOI: 10.31610/zsr/2022.31.1.3 

  Researchgate.net/publication/358210579_A_description_of_Dendronotus_shpataki_from_the_Sea_of_Japan

[PaleoIchthyology • 2026] Parastylephorus anatoides • A New fossil from the Eocene of Iran provides new insights regarding the evolution of the morphologically bizarre tube-eye fish

 

Parastylephorus anatoides 

Ridolfi, Schrøder, Bahrami, Yazdi, Roa-Varón, Marramà & Carnevale, 2026

 

DOI: doi.org/10.1002/spp2.70114

Artwork by Lucrezia Bonardo

Abstract

Stylephoriformes are a morphologically bizarre lineage of deep-sea fishes, currently represented by a single extant species, Stylephorus chordatus, the so-called tube-eye fish. The phylogenetic relationships of the Stylephoriformes were extensively debated until recent genomic studies proposed a sister-group relationship with the Gadiformes. The tube-eye fish exhibits a suite of highly derived features, including extreme cranial kinesis, a pipette-like oral apparatus specialized for suction feeding, and an elongate, naked ribbon-like body lacking scales. The evolutionary origin of these unique traits is largely unknown, in part due to the complete absence of a fossil record. Here, we describe the first-known fossil of the order Stylephoriformes, from Bartonian (c. 40 Ma) sediments of the Pabdeh Formation, Iran. On the basis of several unique morphological features (edentulous premaxillae and dentary, moderately enlarged pterygoid elements, reduced opercle, elongate ribbon-like body comprising more than 63 vertebrae, eight pectoral-fin rays, absence of basipterygia, and the presence of a complete series of well-developed lateral-line scales) the specimen is assigned to a new genus and species: Parastylephorus anatoides. The fossil exhibits a body physiognomy, oral apparatus and cranial architecture remarkably similar to those of the extant tube-eye, with the most derived features already present and closely comparable in morphology. This suggests that the new fossil represents a good example of long-term morphological stasis among marine teleosts, documenting the persistence of a highly specialized body plan for more than 40 myr.

Keywords: Parastylephorus anatoides, Bartonian, Iran, Pabdeh Formation, Paracanthopterygii

Parastylephorus anatoides gen. et sp. nov., holotype, IUGM 100897, from the Eocene of Babaheydar (Iran). Scale bar represents 10 mm.

SYSTEMATIC PALAEONTOLOGY

Order STYLEPHORIFORMES sensu Miya et al. 2007

Family STYLEPHORIDAE Swainson 1839

Genus Parastylephorus nov.

 

Derivation of name: The genus name is derived from the Greek prefix para- (παρά), meaning ‘near’, combined with Stylephorus, the name of the only currently recognized stylephoriform genus. The name reflects the shared morphological characteristics with Stylephorus.

 

Remarks: As discussed above, the Stylephoriformes are a lineage currently represented by a single extant species, Stylephorus chordatus, which possesses a number of highly derived anatomical features, including a strongly modified buccal apparatus, extremely reduced first two vertebral centra, and a continuous dorsal fin along the entire dorsal margin of the body. The body plan of Parastylephorus gen. nov. closely resembles that of Stylephorus, although it has a set of distinctive traits. These include the maxilla with a well-developed posterior process, the expanded metapterygoid and ectopterygoid, and the reduced size of the opercular bones. In addition, Parastylephorus gen. nov. possesses body squamation, consisting of thin and delicate lateral-line scales, which are completely absent in Stylephorus.

Parastylephorus anatoides sp. nov.

 

Derivation of name: The name is derived from the Latin word Anas, meaning ‘duck’, and the Greek suffix -oides (-οειδής) meaning ‘resembling’ or ‘having the form of’.

Holotype: IUGM 100897 a partially preserved specimen on a single plate 

 

Artistic reconstruction of Parastylephorus anatoides gen. et sp. nov. 

Note that the tubular eyes are based on the condition characteristic of the extant Stylephorus chordatus. 

Artwork by Lucrezia Bonardo.

Lorenzo Ridolfi, Ane Elise Schrøder, Ali Bahrami, Mehdi Yazdi, Adela Roa-Varón, Giuseppe Marramà and Giorgio Carnevale. 2026. A New fossil from the Eocene of Iran provides new insights regarding the evolution of the morphologically bizarre tube-eye fish. Papers in Palaeontology. DOI: doi.org/10.1002/spp2.70114 [11 August 2026]

[Ichthyology • 2026] Hippocampus amandavincentae • A New Species of Spiny Seahorse (Syngnathiformes: Syngnathidae) from Indian Ocean, with Redescription of H. histrix and H. jayakari

 

Hippocampus amandavincentae  

Shalu, Short, Raghavan, Ramvilas & Ranjeet, 2026

DOI: doi.org/10.11646/zootaxa.5862.2.4  

 facebook.com/RajeevRAGHAVAN98

 

Abstract

The thorny seahorse, Hippocampus histrix Kaup, 1856, has long been treated as a single, widely distributed species ranging from the Red Sea and western Indian Ocean to the western Pacific. Morphological and molecular evidence now demonstrate that this broad concept encompasses at least three diagnosable species. Examination of Indian Ocean specimens combined with mitochondrial COI sequence analysis reveals a new lineage herein described as Hippocampus amandavincentae sp. nov., based on material from southeastern India and corroborated by published sequences from Madagascar, Mozambique, the Seychelles, and the northern Red Sea. The new species is diagnosed by a shorter snout, five coronet spines, and spines present on all principal trunk and tail ridges. A published COI sequence from the northern Red Sea places H. amandavincentae in apparent sympatry with Hippocampus jayakari Boulenger, 1900, in that region, indicating that the distributional boundary between these two species requires targeted field investigation. Hippocampus histrix sensu stricto is redescribed and its distribution restricted to the Pacific Ocean, including Japan, Indonesia, and the Philippines, based on direct examination of type material. Hippocampus jayakari, described from the Gulf of Oman, is confirmed as a distinct species of the northwestern Indian Ocean, readily distinguished by four cleithral spines with the ventral-most bifurcate, a shorter and deeper snout, and spines confined to alternating tail rings. Together, these three species represent geographically coherent lineages whose delineation resolves over a century of misidentification in museum collections and online databases, stabilises the application of long-used names, and provides a practical framework for regional conservation assessment and future systematic research on spiny seahorses across the Indo-Pacific.

Pisces, barcoding, India, species complex, taxonomy, thorny seahorse

Hippocampus amandavincentae sp. nov.

Hippocampus amandavincentae sp. nov.

Kannan SHALU, Graham SHORT, Rajeev RAGHAVAN, Ghosh RAMVILAS and Kutty RANJEET. 2026. A New Species of Spiny Seahorse, Hippocampus amandavincentae, with Redescription of H. histrix and H. jayakari (Teleostei: Syngnathidae).  Zootaxa. 5862(2); 271-292. DOI: doi.org/10.11646/zootaxa.5862.2.4 [2026-08-05] 

  facebook.com/RajeevRAGHAVAN98/posts/10162487911550938