Showing posts with label Marine. Show all posts
Showing posts with label Marine. Show all posts

Friday, June 12, 2026

[Cnidaria • 2026] Paraplexaura binyuani • A New Gorgonian (Octocorallia: Acanthogorgiidae) from the Huaguang Atoll, Xisha Islands, South China Sea

 
Paraplexaura binyuani 
You, Xia & Liu, 2026. 

斌源似丛柳珊瑚  ||  DOI: doi.org/10.3390/d18030166 

Abstract
A new shallow-water gorgonian coral species in the family Acanthogorgiidae, Paraplexaura binyuani sp. nov., is described from a specimen collected at Huaguang Atoll in the South China Sea at a depth of 22 m. The new species is distinguished from its congeners by abundant polyp sclerites, predominantly flattened rods, and by the coenenchyme bearing numerous large spindles reaching up to 0.6 mm in length, which are approximately two to three times longer than those reported for most described species of Paraplexaura. Phylogenomic analyses based on ultraconserved elements (UCEs) recover Paraplexaura as monophyletic and place P. binyuani sp. nov. as sister to P. cryptotheca, consistent with its morphological distinctiveness and supporting its recognition as a separate species.

Keywords: Malacalcyonacea; shallow-water coral; taxonomy; morphology; ultraconserved elements

 The external morphology and polyps of Paraplexaura binyuani sp. nov. Holotype, GXTCMU-2025-HT005.
(A,C) in situ; (B) After collection; (D) Frontal view of a branch; (E) Polyps under SEM.
 Scale bars indicate 1 cm in (B), 5 mm in (D), 100 μm in (E).

Paraplexaura binyuani sp. nov.

Etymology. The new species is named after Dr. Binyuan He, principal investigator of the Guangxi Academy of Oceanography, and for his great contribution to benthos research of Guangxi. The Chinese name of the new species is “斌源似丛柳珊瑚”

Distribution and habitat. Known only from the subtidal zone of the Huaguang Atoll on the Chinese coast of the South China Sea with a water depth of 22 m. Colony attached to a rocky substrate.
 

Li You, Fei Xia and Xinming Liu. 2026. A New Gorgonian Paraplexaura binyuani sp. nov. (Cnidaria, Octocorallia, Acanthogorgiidae) from the Huaguang Atoll, Xisha Islands, South China Sea. Diversity. 18(3), 166. DOI: doi.org/10.3390/d18030166 [9 March 2026]

Wednesday, May 27, 2026

[Mollusca • 2026] Microeledone galapagensis • A New Species of Microeledone (Octopoda: Incirrata) from Galápagos Islands and an amended diagnosis of the Megaleledonidae

 

Microeledone galapagensis 
Voight, Smith, Buglass & Ziegler, 2026

 
Abstract
The octopod fauna of the deep tropical Pacific Ocean remains poorly known, as is the octopod family Megaleledonidae Taki. A single female megaleledonid specimen collected at 1773 m depth near the equatorial Galápagos island of Darwin is named Microeledone galapagensis sp. nov. This small, squat, short-armed octopod has few arm suckers and gill lamellae. Its lack of a crop diverticulum, ink sac, and anal flaps suggests that it pertains to Thaumeledone. However, its smooth skin, which dorsally is nearly free of pigment, large rachidian tooth, and large funnel organ ally it with the monotypic Microeledone. Its reverse countershading and dense pigmentation on the inner dorsal mantle musculature distinguish this species from Microeledone mangoldi Norman, Hochberg & Boucher-Rodoni, 2004a. This species belies the definition of the Megaleledonidae as large-bodied, Southern Ocean endemics, leading us to revise the family diagnosis. The short arms carrying few suckers in this genus and Thaumeledone are hypothesized to relate to heterochrony, potentially increasing energy available for reproduction and contributing to niche partitioning.

Mollusca, Thaumeledone, heterochrony, Pacific Ocean, deep sea, posterior salivary gland, ink sac, skin texture



Photos of Microeledone galapagensis sp.  nov. 
in situ (a); on recovery dorsal (b) and ventral (c) (photos by the Science Party of the NA064 cruise); in preservation dorsal (d) and ventral (e) views of entire animal. 

Microeledone galapagensis sp. nov. 

Diagnosis. With the characters of the genus; sheath covering inner dorsal mantle muscles heavily pigmented, internal organs lack pigment, except dots near mantle opening on mantle septum, rectum, and anus; posterior salivary glands medium, ca. 70% of buccal mass length; eyes large, slightly projecting.


Janet R. VOIGHT, Stephanie M. SMITH, Salome BUGLASS and Alexander ZIEGLER. 2026. A New Species of Microeledone from Galápagos Islands and an amended diagnosis of the Megaleledonidae (Octopoda: Incirrata). Zootaxa. 5814(4); 533-549. DOI: doi.org/10.11646/zootaxa.5814.4.5 [2026-05-25]

     

Friday, May 22, 2026

[Paleontology • 2026] Tylosaurus rex • A gigantic New Species of Tylosaurus (Squamata: Mosasauridae) from Texas: and A revised character list for phylogenetic analyses of Mosasauridae


Tylosaurus rex
Zietlow, Polcyn & Tykoski, 2026
 

Abstract
At least four subfamily-level clades of mosasaurs are broadly recognized (Mosasaurinae, Plioplatecarpinae, Tylosaurinae, Halisaurinae), each of which independently evolved flippers and other aquatic adaptations, including large body size. Tylosaurine mosasaurs are distinguished from other mosasaurs, in part, by edentulous extensions of both upper and lower jaws, proportionally long tails, and poorly ossified limbs, and they were the first mosasaur clade to achieve gigantic (>8 m) body size. Several tylosaurine species are known from Europe, Asia, New Zealand, Africa, and Antarctica, but they were most common in the Western Interior Seaway of North America. Here, we describe a new species, Tylosaurus rex, sp. nov., from the Campanian of Texas and analyze tylosaurine in-group systematics using a significantly updated phylogenetic character list. Our new species is distinguished by a unique suite of characters, including some associated with increased jaw and neck musculature, and others that may be convergent with other giant mosasaur species (e.g., Mosasaurus). Body length estimates for specimens referred to our new species are consistently larger (7.7–13.2 m) than those for the largest Niobrara species, T. proriger (3.9–9.5 m), although it is unclear whether this is a taxonomic signal or taphonomic bias. Several specimens that we refer to T. rex were previously referred to T. proriger in various collections databases, and some of the traits distinguishing them had been previously attributed to ontogenetic differences. However, we rule out this possibility as specimens of T. proriger and T. rex that do overlap in size can be differentiated by unique suites of diagnostic characters. The implicit association between body size and ontogeny, as well as the general absence of reliable locality and stratigraphic data associated with historical collections of North American mosasaurs, raises the possibility of the presence of other currently unrecognized species, previously dismissed as ontogenetic stages of other species.
 
Keywords: Tylosaurus rex, Tylosaurus, Texas, Classification, Mosasauridae, Phylogeny 



The holotype for the newly described Tylosaurus rex is a giant specimen displayed at the Perot Museum of Nature and Science in Dallas that was first discovered in 1979.
 Perot Museum of Nature and Science

Tylosaurus rex, sp. nov.

A reconstruction of Tylosaurus rex in the Cretaceous-era Western Interior Seaway of North America
artwork by Alderon Games - Path of Titans



Zietlow, Amelia R.; Polcyn, Michael J. and Tykoski, Ronald S. 2026. A gigantic New Species of Tylosaurus (Squamata, Mosasauridae) from Texas: and A revised character list for phylogenetic analyses of Mosasauridae. Bulletin of the American Museum of Natural History. 482; DOI: 10.1206/0003-0090.482.1.1 https://hdl.handle.net/2246/7549

Saturday, May 16, 2026

[Cnidaria • 2026] Chironex blakangmati Chironex box jellyfishes (Cubozoa: Chirodropida) in Singapore: New Species, and Range Extension of C. indrasaksajiae


Chironex blakangmati
Iesa, Ames, Yap & Huang, 2026 

 RAFFLES BULLETIN OF ZOOLOGY. 74

Abstract
 Two venomous box jellyfish species of the genus Chironex Southcott, 1956 (Cnidaria: Cubozoa: Chirodropida) were collected from Singapore’s coastal waters: Chironex indrasaksajiae Sucharitakul, 2017 and a novel species described herein as Chironex blakangmati, new speciesChironex indrasaksajiae was collected from both the Johor and Singapore Straits around mainland Singapore. Chironex blakangmati, new species, was collected from Sentosa Island along the Singapore Strait and is the fourth species described in the genus. While C. blakangmati’s volcano-shaped pedalial canal and tentacle number are similar to C. yamaguchii Lewis & Bentlage, 2009, its elongated, sharp-tipped velarial canals and DNA sequences distinguish it from other Chironex species. Comparisons of Chironex blakangmati, new species, with C. yamaguchii and C. fleckeri reveal novel morphological differences at the terminal end of the perradial lappet along the velarium edge, where C. blakangmati, new species, lacks velarial canals extending from the perradial lappet terminus. Juvenile Chironex yamaguchii specimens were examined and ontogenetic variations of velarial canals are herein reported. Preliminary cnidome analysis reveals eight types of nematocysts observed in C. blakangmati, new species, five types in C. indrasaksajiae, and five types in C. yamaguchii. Molecular phylogenetic reconstruction places C. blakangmati, new species, in a clade distinct from its congeners, as sister group to C. yamaguchii based on 16S rRNA gene analysis but diverging earlier than the clade comprising C. yamaguchii and C. indrasaksajiae based on cytochrome c oxidase subunit I gene analysis for which sequence data are comparatively limited. Understanding the biodiversity and seasonality of venomous cubomedusae will help mitigate the risk they pose to human health and safety during maritime activities. 

Key words. 16S rRNA, COI barcoding, marine biodiversity, phylogenetic analysis, Southeast Asia, venomous

Chironex blakangmati, new species, from Singapore.
A, live individual (paratype, ZRC.CNI.1462), lateral perradius view; B, live individual (holotype, ZRC.CNI.3014), lateral perradius view; C, cockscomb gastric saccule (sac); D, gastric cirri (gc); E, rhopalial niche front view; F, rhopalial niche side view (paratype, ZRC.CNI.1462); G, rhopalial niche side view (holotype, ZRC.CNI.3014); H, tentacle contracted with alternating brown dark bands; I, tentacle stretched; J, preserved tentacle with hollow cross section (arrow); K, pedalium with volcano pedalial canal bend (pcb) marked by arrow; L, U-shaped alternating tentacle pattern with gap marked by an arrow; M, adradial positions (ad) marked by arrows, and rhopalial niche at perradial position (per); N, gastric saccules (sac) surrounding cruciform manubrium (man); O, velarium at perradial position with frenulum (fre) arrowed, lappet terminating in simple triangular tip; P, velarium with candelabrum velarial canal pattern (holotype, ZRC.CNI.3014). rh = rhopalium, rhO = rhopalial ostium, co = convex boundary.

Chironex blakangmati, new species 

Diagnosis. Chironex with conical to cuboidal bell. Seven tentacles per pedalium, branching U-shaped alternating. Pedalial canal bend volcano shaped. Tips of velarial canals sharp towards velarial margin (Fig. 11D), with simple triangular tip at edge of velarium in perradial position (Fig. 3O & Fig. 12). Absence of velarial canals at perradial position where frenulum tapers off (Fig. 12D). 

Etymology. This species is named using Bahasa Melayu, the Austronesian language spoken in the region and the national language of Singapore, for Sentosa Island from which the animal was collected. Sentosa Island was historically referred to as “Pulau Blakang Mati”, meaning “Island of Death Behind” and, as such, “blakangmati” in denoting the geographic location is a noun in apposition. 


Iffah Iesa, Cheryl Lewis Ames, Nicholas Wei Liang Yap and Danwei Huang. 2026. Chironex box jellyfishes (Cnidaria: Cubozoa: Chirodropida) in Singapore: Chironex blakangmati, new species, and range extension of Cindrasaksajiae. RAFFLES BULLETIN OF ZOOLOGY. 74: 383–402. DOI: 10.26107/RBZ-2026-0026 [15 May 2026]


Tuesday, May 12, 2026

[Mollusca • 2026] Thecacera sesama • A New Species of the Genus Thecacera (Nudibranchia: Polyceridae) from Taiwan, evident from morphology and phylogenetic analyses of the 16S rDNA and cytochrome c oxidase I gene

 

Thecacera sesama Chan & Lee,

in Chan, Lee, Chen, Chang, Shao et Pang, 2026. 

Abstract
Thecacera sesama Chan & Lee, sp. nov. (Nudibranchia, Polyceridae) is described from north-eastern Taiwan based on an integrative taxonomic approach combining morphological and molecular data. The new species is distinguished from its congeners by a unique colour pattern consisting of a translucent white body covered with numerous small, round, black pigment spots and fewer, larger, yellow spots and five gills. While sharing a similar spotted colour pattern with Thecacera pennigera, the new species can be clearly distinguished by its significantly smaller body size (maximum length < 3 mm). Phylogenetic analyses of two mitochondrial genes, cytochrome c oxidase subunit I (COI) and 16S rRNA, confirmed it as a new species in Thecacera. The molecular data places Thecacera sesama sp. nov. as a sister species to Thecacera picta, with a significant interspecific COI divergence of 14.17%. This discovery highlights the rich, yet under documented, marine biodiversity of Taiwan and underscores the value of combining traditional morphological examination with molecular phylogenetics for accurate species delimitation in cryptic nudibranch lineages.

Key words: bryozoans, COI, cryptic diversity, Heterobranchia, phylogeny, systematics, taxonomy

Living specimens of Thecacera sesama sp. nov.
A. Ecological photos; B. ASIZM0001722; C. ASIZM0001721. Scale bars: 1 mm.

Thecacera sesama sp. nov.
Details of appearance and morphological features, hand-drawn on a tablet PC by Chen-Lu Lee. 

Thecacera sesama Chan & Lee, sp. nov.
 
Diagnosis. Thecacera sesama sp. nov. is distinguished by a unique combination of the following external morphological characters: (1) maximum preserved length of specimens is 2.83 mm; (2) body colour is translucent whitish, allowing some internal organs to be faintly visible; (3) entire body, as well as the rhinophores, rhinophoral sheaths, gills, post-branchial appendages, propodial tentacles, and tail are covered with numerous, discrete, small, circular, black spots and large yellow spots, as well as many white, snowflake-shaped pigment patches scattered on the body; (4) rhinophores and rhinophoral sheaths are translucent whitish, with small black spots and large yellow spots; (5) rhinophoral lamellae number 9–12; (6) gills number 5 and are translucent whitish, and the branchial plumes are pinnate; (7) post-branchial appendages are translucent whitish; (8) the head is translucent whitish, with short, blunt propodial tentacles at the corners.

Etymology. The specific epithet sesama is derived from the Latin word for sesame seed, referring to the characteristic small, rounded, seed-like spots that cover the dorsal surface of this species, resembling scattered sesame seeds on the animal’s body.


 Ho-Yeung Chan, Chen-Lu Lee, Wei-Cheng Chen, Chia-Hao Chang, Yi-Ta Shao and Ka-Lai Pang. 2026. Thecacera sesama sp. nov. (Nudibranchia, Polyceridae) from Taiwan, evident from morphology and phylogenetic analyses of the 16S rDNA and cytochrome c oxidase I gene. ZooKeys. 1279: 269-284. DOI: doi.org/10.3897/zookeys.1279.184298 [11 May 2026]


[Ichthyology • 2026] Solenostomus snuffleupagus • A hairy Ghost Pipefish (Syngnathiformes: Solenostomidae) from the Southwest Pacific, with an integrative comparison to S. paegnius


Solenostomus snuffleupagus
Short & Harasti, 2026   


 
Abstract
A new species of ghost pipefish, Solenostomus snuffleupagus sp. nov., is described from the Coral Sea based on specimens (18–34 mm SL) collected from coral reef habitats in Queensland, Australia. The species is diagnosed by the following combination of characters: abundant elongate integumentary filaments imparting a conspicuously shaggy appearance; 36 total vertebrae (vs. 32–34 in all congeners); compact body form with a short, deep pretrunk (11%–14% SL); sexually dimorphic supraoccipital crests (moderately elevated in females, strongly developed in males); and two modified anchor-like ossicles spanning the pterygiophores in both soft dorsal and anal fins. Micro-CT imaging reveals distinctive pretrunk ossicle configuration characterized by deep angular interspaces and absence of a ventral ossicle series. Mitochondrial COI sequences indicate an uncorrected p-distance of 22.0% from the superficially similar S. paegnius, a species with which it has long been confused in museum collections and citizen science databases. Field observations document consistent association with dense filamentous red macroalgae, with body coloration closely matching host substrate. The species is currently known from the southwest Pacific, including northeastern Australia (Coral Sea), Papua New Guinea, New Caledonia, Fiji and Tonga, representing a southwestern Pacific distribution.

Solenostomus snuffleupagus, in situ, Great Barrier Reef, Australia, 2022: (a) adult individual; (b) female specimen used for genetic analysis; (c) male specimen used for genetic analysis (photographs by David Harasti).

Micro-CT reconstructions (lateral view) of Solenostomus snuffleupagus:
(a) holotype, female, AMS I.33751-047; (b) paratype, male, NTM S.13600–047. DF, dorsal-fin; PF, pectoral-fin; sAF, soft anal-fin; sDF, soft dorsal-fin. Numbers 1 and 2 indicate the respective pterygiophores supporting the soft dorsal- and anal-fins.

 Taxonomy
Family Solenostomidae 

Genus Solenostomus Lacépède 1803 

 Solenostomus snuffleupagus, Short and Harasti, new species

Diagnosis: A species of Solenostomus distinguished from its congeners by the following combination of characters: body compact and vertically deep anteriorly; pretrunk deep (24.4%–29.2% SL); abundant, elongate integumentary filaments conferring a conspicuously shaggy appearance, particularly dense on snout, jaws, head and fin extremities; pretrunk ossicles are narrow and elongated, separated by deep angular interspaces, forming a distinctive compact lattice; There are total 36 vertebrae. The supraoccipital crest is elevated and rounded in females, but strongly pronounced in males. There are two modified anchor-like ossicles spanning the pterygiophores in both the soft dorsal fin (19–20 rays) and anal fin (18–19 rays). The soft dorsal fin has 19–20 rays, the anal fin has 18–19 rays, the pectoral fin has 27 rays, the caudal fin has 15 rays.

Etymology: The specific epithet snuffleupagus refers to the shaggy character Mr. Snuffleupagus, also known as ‘Snuffy’, from the children's television series Sesame Street™, in allusion to the species' distinctly shaggy, filamentous appearance and snout reminiscent of the character's covering and trunk. The name is treated as a noun in apposition (ICZN Article 31.1.2).

Solenostomus paegnius, in situ: (a) Indonesia (photograph by Richard Smith); (b) Philippines, male–female pair with the female positioned above the male in the water column (photograph by Lynn Funkhouser); (c) Philippines, male–female pair with the female positioned above the male in the water column (photograph by Alex Tyrrell @dive4photos).
 

Graham Short and David Harasti. 2026. Solenostomus snuffleupagus sp. nov., A hairy Ghost Pipefish (Teleostei: Solenostomidae) from the Southwest Pacific, with an integrative comparison to S. paegniusJournal of Fish Biology. DOI: doi.org/10.1111/jfb.70497 [10 May 2026]
 

Wednesday, May 6, 2026

[Crustacea • 2025] Umalia modesta • A New Species of Frog Crab Genus Umalia Guinot, 1993 (Brachyura: Raninidae) from the South China Sea, with A Key to Species in the Genus

 

Umalia modesta
Ng, 2025


Abstract 
A new species of raninid frog crab, Umalia modesta n. sp., is described from the northern part of the South China Sea, near Tungsha Islands. The species is morphologically most similar to U. chinensis (Chen & Sun, 2002) (from southern China) and U. tenuiocellus (Davie & Short, 1989) (from Australia) but can easily be distinguished from them by its carapace form, well developed cornea, and structures of the rostrum, thoracic sternum, third maxilliped and ambulatory legs.  

Key words: Tungsha Islands, Taiwan, Raninoidea, new species, comparative taxonomy, genus key

Umalia modesta n. sp., holotype female (11.0×14.0 mm) (ZRC 2024.0500), South China Sea.
A, overall dorsal view; B, frontal half of carapace (dorsal view); C, frontal view of cephalothorax; D, left anterolateral view of cephalothorax; E, third maxillipeds.

Umalia modesta n. sp., male, station CP4115,
southwest of Tungsha Island, South China Sea [specimen not examined]
[Photograph: T.-Y. Chan].

Superfamily Raninoidea De Haan, 1839 
Family Raninidae De Haan, 1839 
Subfamily Notopodinae Serène & Umali, 1972 

Umalia Guinot, 1993

Umalia modesta, new species 

Diagnosis: Carapace shape trapezoidal, anterior part much wider than posterior part, lateral margins almost straight, subparallel; carapace width more than 0.7 total length; fronto-orbital distance less than half width of carapace; anterior ...

Etymology: From the Latin “modesta” for unassuming, alluding to the simple characters of the species


Peter K. L. Ng. 2025. On A New Species of Frog Crab, Umalia modesta n. sp. (Brachyura: Raninidae) from the South China Sea, with A Key to Species in the Genus. Crustacean Research. 54; 53-61. DOI: doi.org/10.18353/crustacea.54.0_53 [September 27, 2025]

Tuesday, May 5, 2026

[Crustacea • 2026] Frodromia elegans, F. granulosa, ... • Revision of Frodromia McLay, 1993 (Brachyura: Dromiidae) and the Status of Frodromiinae Števčić, 2005


A, Frodromia atypica (Sakai, 1936),; B, F. reticulata (Sakai, 1974);
C, F. elegans, new species, holotype male, Taiwan; D, F. granulosa, new species, holotype male, Vanuatu;
 E, F, F. iners, new species, holotype male, Philippines. 
Ng, 2026 

RAFFLES BULLETIN OF ZOOLOGY. 74
Photographs: C, T.-Y. Chan; D, J.C.E. Mendoza; E, F, P.K.L. Ng.

Abstract
 The taxonomy of the West Pacific dromiid genus, Frodromia McLay, 1993, is revised using a suite of characters pertaining to the carapace form and armature, proportions of the ambulatory dactylus, and structures of the pereopods, thoracic sternum, male pleon, and gonopods. The identity of the poorly known type species, F. atypica (Sakai, 1936), is clarified and the species is rediagnosed and illustrated based on the single non-type dried specimen available. Frodromia reticulata (Sakai, 1974) is also rediagnosed on the basis of a series of Japanese specimens. The material identified as F. atypica by McLay (1993) from New Caledonia and the Indonesian Moluccas is here shown to belong to two new species, F. granulosa and F. caileani, respectively; with F. granulosa also reported from Vanuatu. Two other new speciesF. elegans and F. iners, are described from the South China Sea and the Philippines, respectively. As a result, Frodromia is hereby classified in the subfamily Frodromiinae Števčić, 2005, which was originally established as a tribe in Sphaerodromiinae Guinot & Tavares, 2003, and which is here redefined and rediagnosed.

Key words. sponge crab, Dromioidea, systematics, subfamily definition, new species, key to taxa, Indo-West Pacific

Colour in life. A, Frodromia atypica (Sakai, 1936), after Sakai (1936: pl. 2 fig. 1); B, F. reticulata (Sakai, 1974), after Sakai (1976: pl. 5 fig. 1);
C, F. elegans, new species, holotype male (6.6 × 7.5 mm) (ZRC 2024.0144), Taiwan; D, F. granulosa, new species, holotype male (6.5 × 7.1 mm) (ZRC 2024.0517), Vanuatu;
E, F, F. iners, new species, holotype male (6.3 × 7.0 mm) (ZRC 2024.0518), Philippines [partly covered with sand particles and debris].
Photographs: C, T.-Y. Chan; D, J.C.E. Mendoza; E, F, P.K.L. Ng.

Frodromia granulosa 
F. caileani 
F. elegans 
 F. iners


PETER K. L. NG. 2026. Revision of Frodromia McLay, 1993 (Crustacea: Brachyura: Dromiidae) and the Status of Frodromiinae Števčić, 2005. RAFFLES BULLETIN OF ZOOLOGY. 74: 332–358. DOI: 10.26107/RBZ-2026-0023  [4 May 2026]

Tuesday, April 28, 2026

[Crustacea • 2026] Nephropsis perexigua • A New Species of Nephropsis Wood-Mason, 1872 (Decapoda: Astacidea: Nephropidae) [the World’s Smallest Clawed Lobster]


Nephropsis perexigua
Chan & Chang, 2026


Abstract
Several small specimens of a clawed lobster recently collected off the island of Guadeloupe in the West Indies and originally reported as Nephropsis aculeata Smith, 1881 are found to represent a species new to science. The new species, N. perexigua sp. nov., can be readily separated from N. aculeata by the absence of a dorsal median carina in the abdomen. Nephropsis perexigua sp. nov. actually closely resembles N. pygmaea Chang, Chan & Kumar, 2020 from the West Pacific, but differs in the abdomen being smooth. The shape of the posteromesial plate on the coxa of the pereiopod III is also distinctly different among males of N. perexiguasp. nov., N. aculeata, and N. pygmaea. The large sequence divergence in the barcoding gene COI supports the distinct specific status of the new species. With the carapace length of the largest specimen being 12.1 mm and the smallest ovigerous female only 10.0 mm, N. perexiguasp. nov. is the world’s smallest clawed lobster so far known. An updated key to the species of Nephropsis Wood-Mason, 1872 is provided.



Nephropsis perexigua sp. nov.


Tin-Yam Chan and Su-Ching Chang. 2026. Description of the World’s Smallest Clawed Lobster, A New Species of Nephropsis Wood-Mason, 1872 (Decapoda: Astacidea: Nephropidae). Journal of Crustacean Biology. 46(2); ruag015. DOI: doi.org/10.1093/jcbiol/ruag015 [10 April 2026 ]
 

Friday, April 24, 2026

[Paleontology • 2026] Earliest Octopuses were Giant Top Predators in Cretaceous Oceans


the Late Cretaceous finned octopus species Nanaimoteuthis sp. 

in Ikegam, Mutterlose, Sugiura, Takeda, Derin, ...et Iba, 2026.  
Artwork by Yohei Utsuki. 

Abstract
Top predators drive changes in ecosystem structure. For the last ~370 million years, large-sized vertebrates have dominated the apex of the marine food chain, while invertebrates have served as smaller prey. Here we describe invertebrate top predators from this “age of vertebrates,” the earliest finned octopuses (Cirrata) from Late Cretaceous sediments (~100 to 72 million years ago), as identified based on huge, exceptionally well-preserved fossil jaws and their wear. This extensive wear suggests dynamic crushing of hard skeletons. Asymmetric wear patterns further indicate lateralized behavior, suggesting advanced intelligence. With a calculated total length of ~7 to 19 meters, these octopuses may represent the largest invertebrates thus described, rivaling contemporaneous giant marine reptiles. Our findings show that powerful jaws, and the loss of superficial skeletons, convergently transformed cephalopods and marine vertebrates into huge, intelligent predators.

Huge lower jaws of fossil octopuses and of an extant giant squid. (A and B) The largest lower jaws of the Late Cretaceous finned octopus species Nanaimoteuthis jeletzkyi [(A) NMNS DS00042 3LmvTpM] and N. haggarti [(B) KMNH IvP 902001]. Both specimens show extensive loss of jaw material caused by wear.
(C) A lower jaw of the extant giant squid Architeuthis dux (NSMT-Mo 85956), a species having the largest jaw among modern cephalopods.
(A) is a digital fossil jaw visualized as a 3D model; (B) is an exceptionally well-preserved nondigital fossil jaw; and (C) is a modern jaw dissected from a carcass of ~10 m total body length. Solid lines indicate the extension of striation on the outer surface of the hood and broken lines show the estimated outline of the rostrum without wear. The hood and lateral walls lost by weathering, shown as shadowed areas, are reconstructed based on the holotype and specimens in fig. S4. (A) and (C) are exhibited in a mirrored position. Scale bar, 20 mm.

A sketch of the giant octopus.
artwork by Yohei Utsuki. 

 
Shin Ikegam, Jörg Mutterlose, Kanta Sugiura, Yusuke Takeda, Mehmet Oguz Derin, Aya Kubota, Kazuki Tainaka, Takahiro Harada, Harufumi Nishida and Yasuhiro Iba. 2026. Earliest Octopuses were Giant Top Predators in Cretaceous Oceans. Science. 392; 6796: 406-410. DOI: doi.org/10.1126/science.aea6285 [23 Apr 2026] 

Editor’s summary: The Kraken, the giant cephalopod of legend, was feared by sailors for centuries. Later interpretations suggested that it may have been based on sightings of the giant squid, which can be 10 meters long. Although they lived far too early to have been the source of the legend, Ikegami et al. describe fossil octopods from the late Cretaceous that truly would have fit the description of the monster, reaching up to 19 meters in length. Wear patterns on their jaws suggest that these octopods preyed upon the large reptiles present at the time, including plesiosaurs and mosasaurs. The authors interpret asymmetry in these wear patterns as an indication of corresponding asymmetry in behavior, suggesting complex brain development and, potentially, high intelligence. —Sacha Vignieri

Monday, April 20, 2026

[Ichthyology • 2026] Redefinition of Stemonosudis intermedia (Ege, 1933) (Aulopiformes: Paralepididae) and Description of Stemonosudis dianea, A New Species from the western Atlantic Ocean


[A-B] Stemonosudis dianea  Ho & Bemis, 2026 
Stemonosudis intermedia  (Ege, 1933)
 
 
Abstract
We examined specimens of slender barracudina in the genus Stemonosudis collected from the western Atlantic Ocean. Investigation revealed that seven specimens represent the first adult records of Stemonosudis intermedia (Ege, 1933), previously known only from juveniles. We redescribed S. intermedia based on the holotype and newly recognized adult and juvenile specimens, and using this ontogenetic series, we document changes in coloration from light-brown juveniles to black adults. We also determined that some specimens from the western Atlantic Ocean previously identified as S. intermedia represent a new species, which we describe herein based on three adults and five juvenile specimens. The new species differs from congeners by having 43–44 anal-fin rays, 117–121 total vertebrae and a pale mouth, gill chamber and gill arches, among a combination of other characters. We also provide information on the lectotype of S. similis (Ege, 1957), which remains known only from the type series.

Keywords: biodiversity, biogeography, Ichthyology, nomenclature, taxonomy


Stemonosudis dianea sp. nov., fresh coloration.
(a) Holotype USNM 407498, 332 mm SL, photograph by Cristina Castillo.
(b) Paratype USNM 407509, 348 mm SL, photograph by Sandra Raredon.

 Stemonosudis dianea sp. nov.
English name: Diane's Slender Barracudina

Stemonosudis intermedia (Ege, 1933), fresh coloration of adults. Right side photographed, reflected to face left. USNM 407096, 277 mm SL. (a) Lateral view of body. (b) Close up of head.
Photographs by Ross Robertson.


Hsuan-Ching Ho and Katherine E. Bemis. 2026. Redefinition of Stemonosudis intermedia (Ege, 1933) and Description of A New Species from the western Atlantic Ocean (Aulopiformes: Paralepididae). Journal of Fish Biology. DOI: doi.org/10.1111/jfb.70342 [30 March 2026]
https://www.fisheries.noaa.gov/feature-story/ferocious-predator-and-important-prey-new-barracudina-species-named-smithsonian


Thursday, April 16, 2026

[Cnidaria • 2026] Chrysogorgia pugnioides, Iridogorgia acutisclerita, I. levisquama • Systematics and Biogeography of Chrysogorgiidae (Anthozoa: Octocorallia) from the Indian Ocean: discovery of New Species on Deep-sea Ridges


Iridogorgia acutisclerita Ge, Zhang & Xu,

in Ge, N. Xu, Hu, Tian, Li, Y. Xu, Wang, Zhang et Q. Xu, 2026. 

Abstract
Species of the family Chrysogorgiidae are distributed worldwide in deep-sea environments. However, most recorded species of this family were from the Atlantic and Pacific Oceans, with only a few reports from the Indian Ocean, particularly from ridge regions. This study describes three new species and reports two known species from Indian Ocean ridges, integrating morphological and molecular analyses (mtMutS and 28S rDNA). Chrysogorgia pugnioides Ge, Hu & Xu, sp. nov. is characterized by fist-like polyps; warty spindles in tentacles; flat and irregular spindles and elongate scales in the polyp body wall; and slender and smooth scales with toothed to irregular edges in the coenenchyme. Iridogorgia acutisclerita Ge, Zhang & Xu, sp. nov. resembles I. splendens but differs by possessing needles and pointed elongate scales in the polyp body wall. Iridogorgia levisquama Ge, Zhang & Xu, sp. nov. is differentiated from the congeneric I. squarrosa by slender and smooth scales with sharp ends in the polyp body wall and needles with fine wartiness in the tentacles. Parachrysogorgia chryseis and Metallogorgia melanotrichos are reported as new records for the Indian Ocean ridges. These findings expand the known biodiversity and biogeographic range of Chrysogorgiidae in the Indian Ocean ridges.

Key Words: Carlsberg Ridge, Chrysogorgiidae, Ninetyeast Ridge, phylogeny, taxonomy

Chrysogorgia pugnioides Ge, Hu & Xu, sp. nov.  

Iridogorgia acutisclerita Ge, Zhang & Xu, sp. nov. 
Iridogorgia levisquama Ge, Zhang & Xu, sp. nov.

The external morphology of Iridogorgia acutisclerita Ge, Zhang & Xu, sp. nov.
 A. Holotype FIO-IND72-JLBEN22309 in situ; B. Paratype FIO-IND72-JLBEN22402 in situ; C–E. Holotype FIO-IND72-JLBEN22309, paratype FIO-IND72-JLBEN22402, and FIO-IND72-JLBEN225511 after collection;
F. Single polyp under a light microscope; G. Single polyp under SEM; H. A part of the tentacle under SEM; I. A part of the branch under a light microscope; J. A part of the branch with epidermal tissue removed under SEM; K. A part of the branch with epidermal tissue under SEM.
Scale bars: 20 cm (C–E); 1 mm (F, I); 500 μm (G, K); 250 μm (H, J).


 Meiling Ge, Ningxia Xu, Xuying Hu, Xin Tian, Xinlong Li, Yu Xu, Zongling Wang, Xuelei Zhang and Qingzeng Xu. 2026. Systematics and Biogeography of Chrysogorgiidae from the Indian Ocean: discovery of New Species on Deep-sea Ridges. Zoosystematics and Evolution. 102(2): 621-647.  DOI: doi.org/10.3897/zse.102.182492 [07 Apr 2026]

Thursday, April 9, 2026

[Ichthyology • 2021] Lethrinus mitchelli • A New Species of Emperor Fish (Acanthuriformes: Lethrinidae) from Milne Bay Province, Papua New Guinea


Lethrinus mitchelli
Allen, Victor & Erdmann, 2021


Abstract 
A new species of emperor fish, Lethrinus mitchelli, is described on the basis of three specimens, 109.4–111.3 mm SL, collected from 20 m at the East Cape region of Milne Bay Province, Papua New Guinea. It is similar to the sympatric relatives L. semicinctus and L. rubrioperculatus, but differs in color pattern and has a narrower cheek (cheek height 3.2–3.6 in head length vs. 2.4–2.9). Other diagnostic features include head length (2.7 in SL) greater than body depth (3.0–3.1 in SL); the snout excluding the lip 1.3–1.4 in cheek height; the snout profile nearly straight, without a prominent hump, and about 55° to the upper jaw; conical lateral jaw teeth; the interorbital area nearly flat or convex; the fourth dorsal-fin spine longest; lateral-line scales 47; transverse scale rows below and above the lateral line 15 and 4.5 rows; and a fully-scaled area adjacent to the prominent bony spine at the posteriormost margin of the opercle (excluding fleshy flap). The new species has a distinctive color pattern: brown dorsally, whitish ventrally, with a broad, brown, posteriorly tapering band on the midlateral body, partially split anteriorly by a relatively broad, ascending diagonal white band. Lethrinus mitchelli is 6.11% sequence divergent (pairwise) in the mtDNA COI marker from its nearest relative, L. semicinctus, also from the East Indies. A table of COI divergences among mtDNA lineages assigned to 27 of the 28 known species of Lethrinus shows a set of distinctly different lineages, from 3.32% to 20.85% divergent from each other (minimum interspecific distances). 

Key words: taxonomy, ichthyology, phylogenetics, coral reef fishes, Indo-Pacific, DNA barcodes, mtDNA COI 

Lethrinus mitchelli n. sp.
blotchy pattern on rubble bottom, about 200 mm SL, East Cape Region, Milne Bay Province, Papua New Guinea
 preserved holotype, 110.1 mm SL, East Cape Region, Milne Bay Province, Papua New Guinea.
photos: G.R. Allen.

Lethrinus mitchelli n. sp.
[upper] about 200 mm SL, East Cape Region, Milne Bay Prov., Papua New Guinea; 
[lower] blotchy pattern on rubble bottom, about 200 mm SL, East Cape Region, Milne Bay Province, Papua New Guinea.
photos: G.R. Allen


 Allen, G.R., Victor, B.C. and Erdmann, M.V. 2021. Lethrinus mitchelli, A New Species of Emperor Fish (Teleostei: Lethrinidae) from Milne Bay Province, Papua New Guinea. Journal of the Ocean Science Foundation. 38, 66–77. DOI: doi.org/10.5281/zenodo.5172763