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Showing posts with label Brachyura. Show all posts
Showing posts with label Brachyura. Show all posts

Tuesday, December 17, 2024

[Crustacea • 2022] Bellayra gen. nov. • Redescription of Philyra sexangula Alcock, 1896 (Decapoda: Brachyura: Leucosiidae), with Description of A New Genus and Species from the northern Indian Ocean

  


Bellayra sexangula (Alcock, 1896) gen. nov., comb. nov.
 Bellayra persicum gen. nov., sp. nov.
Trivedi, Naderloo, Viswanathan & Mitra, 2022 

 
Abstract
The identity of Philyra sexangula Alcock, 1896 (Leucosiidae), an inhabitant of mangrove habitats, is clarified. The redescription of the lectotype male and examination of fresh material collected from Pichavaram mangrove forest located in Tamil Nadu State of India revealed that P. sexangula shows significant morphological differences from the generic characters of Philyra sensu stricto. Therefore, a new genus Bellayra gen. nov., is established herewith for the species. In addition, one new species, Bellayra persicum gen. nov., sp. nov., is described based on a syntype male of P. sexangula collected from the Persian Gulf. Furthermore, Philyra taekoae Takeda, 1972 and Philyra nishihirai Takeda and Nakasone, 1991, described from Japan are also transferred to Bellayra gen. nov.

Keywords: India; Leucosiidae; mangroves; Persian Gulf; Systematics

SYSTEMATICS
Family Leucosiidae Samouelle, 1819

Bellayra gen. nov.

Diagnosis. Carapace rhomboidal, markedly punctuate, punctae extending to ventral surface; regions well defined with granules. Anterolateral and posterolateral margins of carapace with obtuse tubercle. Male pleon (Figs. 1d, 2d) with 3 articulating somites, somite 1 narrow, median part slightly protruding, somites 2 - 6 tightly fused, distinct median denticle on somite 6, telson with rounded apex; female pleon with 4 articulating somites, somites 3 - 6 tightly fused. G1 straight or twisted with broad triangular or twisted apical lobe.

Etymology: The genus is named in honor of Bella Galil for her valuable contribution to the taxonomy of the family Leucosiidae. The name is in arbitrary combination with the suffix of the genus name Philyra.


Bellayra sexangula gen. nov., comb. nov., lectotype, male (CL 7.24 mm, CB 7.85 mm) (ZSI-893/10). a, Habitus, dorsal view; b, right cheliped, outer view; c, right cheliped, inner view; d, carapace, ventral view.

Bellayra sexangula (Alcock, 1896) gen. nov., comb. nov.

Bellayra persicum gen. nov., sp. nov.

Etymology. The species name is derived from the type locality, Persian Gulf, which is called “Sinus Persicus” in the ancient Greek literature.

 Bellayra persicum gen. nov., sp. nov., holotype, male (CL 7.88 mm, CB 7.83 mm) (ZSI-896/10). a, Habitus, dorsal view; b, right cheliped, outer view; c, right cheliped, inner view; d, carapace, ventral view; e, carapace, lateral view. 


Jigneshkumar Trivedi, Reza Naderloo, Chinnathambi Viswanathan and Santanu Mitra. 2022. Redescription of Philyra sexangula Alcock, 1896 (Decapoda, Brachyura, Leucosiidae), with Description of A New Genus and Species from the northern Indian Ocean. Nauplius. 30. DOI: doi.org/10.1590/2358-2936e2022026 

Monday, November 25, 2024

[Crustacea • 2024] Phalangipus somnathensis • A New Species of Spider Crab from India, Arabian Sea, with A Key to the Species of Phalangipus Latreille, 1828 (Decapoda: Brachyura: Epialtidae)


Phalangipus somnathensis
Sureandiran, Karuppasamy & Suyani, 2024


Abstract
A new species of spider crab is described based on a single specimen collected from the Veraval fishing harbour, Gujarat, north-west coast of India, Arabian Sea. Globally nine species of spider crabs were reported of which four, Phalangipus filiformis, P. hystrix, P. indicus and P. longipes were documented from Indian waters. The new species, P. somnathensis sp. nov. differs from most species of the genus, based on the presence of blunt spines over the lateral & dorsal margin of the carapace, by the intestinal region being produced into a sharp spine, and by possessing a unique shape of male pleopod, i.e., branched into two lobes distally. The newly discovered species is compared with its congeners.

Keywords: Epialtidae; Gujarat; new discovery; Phalangipus somnathensis sp. nov.; pleopod;



 B. Sureandiran, K. Karuppasamy and N. K. Suyani. 2024. Phalangipus somnathensis sp. nov. (Decapoda, Brachyura, Epialtidae) A New Species of Spider Crab from India, Arabian Sea, with A Key to the Species of Phalangipus Latreille, 1828.  Crustaceana.  97(10-11); 1373–1381. DOI: doi.org/10.1163/15685403-bja10423


Saturday, September 21, 2024

[Paleontology • 2024] Decapod Crustacean Diversity through time and space in a middle-upper Eocene carbonate-siliciclastic platform (southern Jaca Basin, Pyrenees, Spain)


Simplified reconstruction of the study area with the distribution of different facies and the different assemblages of crabs found in different environments. A-F: different decapod assemblages of the studied area (only Brachyura).
A: Belsué Platform beds (Proximal-shallow); B: Arguis platform beds (proximal); C: Coral buldups; D: Pectinid platform beds; E: Bryozoan beds; F: Arguis platform beds (distal) and Belsué platform beds (deep). The geographical subdivisions produced by the different anticlines have been omitted to simplify the scheme. Individually framed taxa have larger distribution areas, marked with a dashed line of the same colour as each box where their record is less fragmentary preservation and scattered remains, and a solid line of the same colour where their record is less fragmentary and continuous.
Taxa: 1: Carpiliidae indet. 1; 2: Calappilia sp.; 3: Lophoranina sp.; 4: Notopus sp.; 5: Galenopsis crassifrons; 6: Liopsalis anodon; 7: Carpiliidae indet. 2; 8: Gemmellarocarcinus riglosensis; 9: Daira corallina; 10: Pyreneplax cf. basaensis; 11: Portunus catalaunicus; 12: Montezumella cf. amenosi; 13: Retrocypoda almelai; 14: Retropluma eocenica; 15: Magyarcarcinus yebraensis; 16: Harpactocarcinus punctulatus; 17: Micromaia priabonensis?; 18: Leucosidae indet.; 19: Quasilaeviranina sp.; 20: Hepatiscus sp.; 21: Periacanthus horridus Bittner, 1875 . (A11–13, B20–21, D17, E1–2, F14 and 16 reused from Ferratges, 2017 ; C5 and 9 reused from Ferratges et al., 2020a ).

in Ferratges, Zamora, Klompmaker et Aurell, 2024. 
 
Highlights: 
• Diverse Eocene invertebrate fauna assemblage found in the Spanish Pyrenees.
• One of first regional studies on decapod distribution in various environments.
• We quantify diversity and abundance of decapod crustaceans in different facies.
• Faunal changes across stratigraphic sequences controlled by tectonics and sediment input.

Abstract
The south-central margin of the Jaca Basin (South-central Pyrenees, Spain) offers well-exposed outcrops ideal for studying the distribution of decapod crustaceans across a mixed carbonate-siliciclastic depositional system during the middle-late Eocene (Bartonian-Priabonian). This study encompasses an area of 1000 km2, featuring environments from siliciclastic coastal plains and deltaic complexes to shallow carbonate and mixed platforms, including coral reefs, extending to prodelta/outer platform deeper conditions. Detailed sampling in four depositional sequences yielded 372 fossil decapod specimens from various lithofacies across 20 localities.

Our analysis identifies 39 decapod species within 22 families and demonstrates ecological zonation of decapods in shallow to relatively deep environments. Diversity peaks in siliciclastic shallow proximal prodelta areas and carbonate bryozoan meadows. Species distribution between carbonate and siliciclastic facies is similar, though taxonomically distinct. Articulated specimens predominantly occur in shallow proximal and relatively deep distal siliciclastic areas, linked to sudden sediment input and high sedimentation rates. These findings elucidate the spatial and temporal distribution factors of decapod crustaceans during the middle-late Eocene, contributing to the broader understanding of palaeoecological patterns in mixed depositional systems.

 Keywords: Crustacea, Taxonomy, Bartonian, Priabonian, Palaeoenvironments, Palaeoecology

 
Fernando A. Ferratges, Samuel Zamora, Adiël A. Klompmaker and Marcos Aurell. 2024. Decapod Crustacean Diversity through time and space in a middle-upper Eocene carbonate-siliciclastic platform (southern Jaca Basin, Pyrenees, Spain). Palaeogeography, Palaeoclimatology, Palaeoecology. 650; 112373. DOI: doi.org/10.1016/j.palaeo.2024.112373

Monday, August 26, 2024

[Crustacea • 2024] Parapyxidognathus tshiansue & P. ongia • A Review of the varunid crab Genus Parapyxidognathus Ward, 1941 (Decapoda: Brachyura: Varunidae), with Descriptions of Two New Species

  
Parapyxidognathus tshiansue
 Hsu & Shih, 2024


Abstract
Species of Parapyxidognathus Ward, 1941 are distributed across tropical Indo-West Pacific to temperate downstream rivers and in estuaries. The genus previously included only one species, Parapyxidognathus deianira (De Man, 1888). We examined specimens from Parapyxidognathus and its closely related genus, Pyxidognathus A. Milne-Edwards, 1879 from the eastern Indian Ocean and western Pacific, focusing on their morphological characters. The results also support the reclassification of Pyxidognathus fluviatilis Alcock, 1900 into Parapyxidognathus, as well as the establishment of two new species from the western Pacific, Pa. tshiansue sp. nov. and Pa. ongia sp. nov. The identity of the species is supported by evidence from mitochondrial 16S rDNA and cytochrome oxidase subunit 1 (COI) genes. There are now four species in Parapyxidognathus distinguishable by the characters of the anterolateral teeth of the carapace, the pleon, and the first gonopods of the male, and the female vulvae.

  
Parapyxidognathus tshiansue sp. nov. 
Parapyxidognathus ongia sp. nov. 



Jhih-Wei Hsu and Hsi-Te Shih. 2024. A Review of the varunid crab Genus Parapyxidognathus Ward, 1941 (Decapoda: Brachyura: Varunidae), with Descriptions of Two New Species. Journal of Crustacean Biology., 44(2); ruae039. DOI: doi.org/10.1093/jcbiol/ruae039

Wednesday, July 10, 2024

[Crustacea • 2024] Gothus teemo • Morphological and Molecular Evidence for A New xanthid Crab (Brachyura: Xanthoidea: Xanthidae) from Coral Reefs in the South China Sea, with A Review of the Taxonomy of Actaeodes consobrinus (A. Milne-Edwards, 1867)


Gothus teemo 
Yuan, Jiang & Sha, 2024 
 

Abstract
A new genus and species within the family Xanthidae MacLeay, 1838, are described from coral reefs in the South China Sea. The new genus, Gothus, with its type species G. teemo sp. nov., is distinguishable from allied genera by characteristics of the carapace, chelipeds, and male pleon. Based on morphological evidence, we tentatively place this genus within the subfamily Euxanthinae Alcock, 1898. However, molecular systematic analysis based on COI, 12S, 16S, and H3 indicates that it does not form a stable monophyletic group with any related subfamily. Another species, Actaeodes consobrinus (A. Milne-Edwards, 1873), is also reclassified into this new genus, based on both morphological and molecular evidence.

Key Words: Euxanthinae, integrative taxonomy, Nansha Islands, Xanthidae, Xisha Islands

Gothus teemo sp. nov.
A–C. Holotype, male, CW 3.7 mm, CL 2.6 mm, MBM287027; D–F. Paratype, CW 3.2 mm, CL 2.2 mm, MBM287026;
A, D. Dorsal view; B, E. Frontal view; C, F. Carapace.
Scale bar: 1 mm.
 
Gothus teemo sp. nov.
A, B. Holotype, male, CW 3.7 mm, CL 2.6 mm, MBM287027;
C–E. Paratypes, 2 juvenile, CW 1.8–2.2 mm, CL 1.3–1.5 mm, MBM287023;
A–D. Live coloration; E. Habitat and substrate conditions. Scale bar: 1 mm.

Family Xanthidae MacLeay, 1838
Subfamily Euxanthinae Alcock, 1898

 Gothus gen. nov.
 
Diagnosis: 
Small species, CW under 10 mm. Carapace broader than long, dorsal surface bearing round granules, regions clearly defined; front wide, not protruding, divided into two slightly triangular lobes by a V-shaped notch; frontal lobes and dorsal inner orbital angle separated by shallow depression; eyestalks densely granulated; area beneath outer orbital angle slightly concave, not forming a subhepatic cavity; anterolateral margin with four teeth, first tooth flattened, sometimes completely reduced to appear as three teeth; posterolateral margin almost straight; subhepatic region densely granulated.

Epistome central region with low median projection on posterior margin. Maxilliped 3 granulated, anterior edge of ...


Etymology: The genus is named after the game of Go, alluding to the intermingled black and white patterns on the carapace, beneath which lie circular granules resembling the pieces of the game. “-thus” is a common suffix for species names within the Xanthidae family. Gender masculine.

 Gothus teemo sp. nov.

Etymology: The new species is named after Teemo, a character from the MOBA (Multiplayer Online Battle Arena) video game League of Legends. This character, modeled after a raccoon, has a fluffy, diminutive stature with a brown and white intermingled fur coat. This alludes to the new species’ small size, densely covered short setae, and brown-striped coloration.

Distribution: Currently known from the type locality at Triton Island, Xisha Islands (Paracel Islands), and Meiji Reef (Mischief Reef), Nansha Islands (Spratly Islands), it inhabits crevices in shallow coral reefs.


 Zi-Ming Yuan, Wei Jiang and Zhong-Li Sha. 2024. Morphological and Molecular Evidence for Gothus teemo gen. et sp. nov., A New xanthid Crab (Crustacea, Brachyura, Xanthoidea) from Coral Reefs in the South China Sea, with A Review of the Taxonomy of Actaeodes consobrinus (A. Milne-Edwards, 1867). and Evolution. 100(3): 965-987. DOI: doi.org/10.3897/zse.100.117859

Tuesday, May 21, 2024

[Crustacea • 2023] Stoliczia setoiyenica • A New Species of Freshwater Crab (Decapoda: Brachyura: Potamidae) from southern Thailand


 Stoliczia setoiyenica
 Tan, Lheknim & Ng, 2023
 
 
Abstract
A new species of freshwater crab is described from southern Thailand, near the border with Peninsular Malaysia. Species of Stoliczia are characterised by their relatively flat carapace, a third maxilliped exopod that possesses no or a very short flagellum, and a conical male gonopod terminal segment that lacks or only has a very low dorsal fold. Stoliczia setoiyenica, new species, most closely resembles S. perlensis and S. kedahensis from northern Peninsula Malaysia but can be easily distinguished from congeners by differences in carapace and male gonopod morphology. Comparisons to the two known Thai Stoliczia species, S. panhai and S. ekavibhathai, are also provided for completeness.

Crustacea, Satun Province, Isthmus of Kra, Potamoidea, taxonomy



Stoliczia setoiyenica, new species


 Zhi Wan Tan, Vachira Lheknim, and Peter K. L. Ng. 2023. Stoliczia setoiyenica, A New Species of Freshwater Crab from southern Thailand (Crustacea: Decapoda: Brachyura: Potamidae).  Zootaxa. 5360(4); 531-544. DOI: 10.11646/zootaxa.5360.4.4

Tuesday, May 14, 2024

[Crustacea • 2024] Demanietta moror • A New Species of Freshwater Crab (Brachyura: Potamidae) from A Karst Formation in southern Thailand


Abstract
A new species of potamid crab belonging to the genus Demanietta Bott, 1966 is described from a creek draining out of a karst formation associated with the Phuket Mountain Range in southern Thailand. Demanietta moror new species, belongs to a group of Demanietta species that has a relatively inflated and smooth carapace, and a male first gonopod that is weakly bent, appearing more vertically projected. It can be immediately distinguished from all congeners by its carapace, gonopod morphology and unique colour pattern in life.

Keywords: Surat Thani Province; Isthmus of Kra; taxonomy; Potamoidea



Demanietta moror new species


 Zhi Wan Tan, Vachira Lheknim, and Peter K. L. Ng. 2024. A New Species of Freshwater Crab, Demanietta moror, from A Karst Formation in southern Thailand (Brachyura, Potamidae).  Crustaceana. 97(3-4); 307–319. DOI: 10.1163/15685403-bja10362


Résumé: Une nouvelle espèce de crabe Potamidae appartenant au genre Demanietta Bott, 1966, est décrite d’un ruisseau s’écoulant d’une formation karstique associée à la chaîne de montagnes de Phuket, dans le sud de la Thaïlande. Demanietta moror n. sp., appartient à un groupe d’espèces du genre Demanietta qui possède une carapace lisse et relativement bombée, et un premier gonopode mâle faiblement recourbé, apparaissant projeté plus verticalement. Elle se distingue immédiatement de tous ses congénères par sa carapace, la morphologie du gonopode et une couleur unique à l’état vivant.

Sunday, May 12, 2024

[Crustacea • 2024] Sundathelphusa roberti • A New Species of Freshwater Crab (Brachyura: Gecarcinucidae) from Highlands in Batangas, Luzon, Philippines


Sundathelphusa roberti
Ng & Mendoza, 2024

 
Abstract
A new species of freshwater crab belonging to a group of species morphologically similar to Sundathelphusa philippina (Von Martens, 1868) is described from highlands in the province of Batangas, southern Luzon, Philippines. Sundathelphusa roberti new species, however, differs from members of this group by the position and strength of the epigastric and postorbital cristae, form of the posterior epistomal margin, shape of the third maxillipeds, and structure of the male first gonopod. The new taxon is the 35th species of Sundathelphusa known from the Philippines.

Keywords: Gecarcinucoidea; comparative taxonomy; description; montane species; Southeast Asia;

 
Sundathelphusa roberti new species


 Peter K. L. Ng and Jose C. E. Mendoza. 2024. A New Species of Freshwater Crab, Sundathelphusa roberti (Brachyura, Gecarcinucidae) from Highlands in Batangas, Luzon, Philippines.  Crustaceana. 97(3-4); 221–233. DOI: 10.1163/15685403-bja10364


Tuesday, April 30, 2024

[Crustacea • 2024] Indochinamon datii • A New Species of the Genus Indochinamon Yeo & Ng, 2007 (Brachyura: Potamoidea: Potamidae) and a new country record from Northern Vietnam


Indochinamon datii 
Dang, Hoang & Do, 2024
    

Abstract
A new species of freshwater crab, Indochinamon datii n. sp. is described from Xuan Son National Park, Phu Tho Province, Northern Vietnam. The new species external morphology is most similar to I. kimboiense (Dang, 1967) and I. bavi Naruse, Nguyen & Yeo, 2011. However, it can be distinguished from the other species by characters of the carapace, telson and male first gonopod. Indochinamon malipoense Zhang & Sun in Zhang, Pan, Hao & Sun, 2020 is also recorded for the first time in Vietnam.

Crustacea, Xuan Son National Park, Phu Tho Province, new record, taxonomy, Potamiscinae, Indochinamon malipoense, Indochinamon ahkense, karsts



 Indochinamon datii n. sp.


Khai Dang, Anh Tram Hoang and Cuong Do. 2024. A New Species of the Genus Indochinamon Yeo & Ng, 2007 (Crustacea: Brachyura: Potamoidea: Potamidae) and a new country record from Northern Vietnam.  Zootaxa. 5437(4); 560-570. DOI: 10.11646/zootaxa.5437.4.8

Monday, April 22, 2024

[Crustacea • 2024] The “Mr. and Mrs. Ghat crab”, Ghatiana dvirupa sp. nov. (Decapoda: Brachyura: Gecarcinucidae) from the Central Western Ghats of India

 

Ghatiana dvirupa 
 Pati,  Bajantri & Hegde, 2024


Abstract
A new species of gecarcinucid freshwater crab, Ghatiana dvirupa sp. nov., is described herein from the Kali Tiger Reserve of the Uttara Kannada district, Karnataka state, India. The Kali Tiger Reserve is a protected area, which is situated in the Central Western Ghats. The new species superficially most resembles Ghatiana sanguinolenta Pati, Thackeray & Pawar, 2023, from Karnataka but can easily be distinguished mainly by its ultimate article of the male first gonopod, which is distally gently curved inwards against the gently outwardly curved distal portion of the ultimate article in the latter species. Ghatiana dvirupa sp. nov. is also compared with the remaining species of the genus from Karnataka and some morphologically related species from Maharashtra. The difference in colour in life has been noticed between males and females of G. dvirupa sp. nov.; as such the common name of the new species is proposed as “Mr. and Mrs. Ghat Crab”. Ghatiana Pati & Sharma, 2014, is now known for 13 species, all from the Western Ghats of India. Karnataka currently possesses six species of Ghatiana, and many new species are yet to be described.
 
Crustacea, Taxonomy, new species, freshwater crab, Karnataka 


Ghatiana dvirupa sp. nov., colour in life: A, holotype male, ZSI-WRC C.2443; B, male, ZSI-WRC C.2447; C, paratype female, ZSI-WRC C.2444; D, paratype female, ZSI-WRC C.2446. Habitats of Ghatiana dvirupa sp. nov.: E, general habitat at type locality; F, male, ZSI-WRC C.2447, in crevice of laterite boulder.
Ghatiana aurantiaca Pati & Sharma, 2014, colour in life: G, crab in its natural habitat during wet season (31 August 2013); H, crab outside of its habitat during dry season (28 November 2011). Figure G is credited to Satyen Mehta, which is modified from inaturalist.org/observations/51882255


Sameer Kumar Pati, Parashuram Prabhu Bajantri, Gopalkrishna Dattatraya Hegde. 2024. The “Mr. and Mrs. Ghat crab”, Ghatiana dvirupa sp. nov. (Decapoda: Brachyura: Gecarcinucidae) from the Central Western Ghats of India.  Zootaxa. 5443(1); 116-126. DOI: 10.11646/zootaxa.5443.1.6
 

Monday, April 8, 2024

[Crustacea • 2018] Helice epicure • A New Species of Varunid Mud Crab (Brachyura: Decapoda: Grapsoidea: Varunidae) from the Ryukyus, Japan


Helice epicure 
Ng, Naruse & Shih, 2018


Helice epicure, a new species of varunid crab, is described from the Ryukyu Islands, Japan. The new species in the genus Helice De Haan, 1833 can be distinguished from its congeners by morphological differences in the chelae and suborbital crenulation. The morphological differences between the new species and a sister clade (the H. latimera complex, including H. latimera Parisi, 1918, H. tientsinensis Rathbun, 1931 and H. formosensis Rathbun, 1931) are supported by mitochondrial cytochrome oxidase subunit I (COI) divergences. However, the phylogenetic relationship within the H. latimera complex is unresolved for the time being.

Key words: Helice epicure, H. formosensis, New species, Varunidae, Mitochondrial cytochrome oxidase subunit I.

  Helice epicure sp. nov. Paratype, male (26.4 × 30.1 mm) (RUMF-ZC-3069).
(A) dorsal entire view; (B) cephalothorax, ventral view; (C) right chela, outer view.


Helice epicure, sp. nov.

Etymology: The species name ‘epicure’ is used here as a Latin noun, derived from ‘epikouros’, a noun in Greek for ‘food lover’ or a person who takes particular pleasure in fine food and drink; this alludes to the late Professor Michael Türkay, a food connoisseur, who strongly believed in eating well and working hard. ‘Epikouros’ in Latin is ‘Epicurus’, also the name of a famous ancient Greek philosopher, whose insistence that nothing should be believed except that which was tested through direct observation and logical deduction made him a key figure in the development of science and scientific methodology. 

Distribution: The new species is found in central to southern Ryukyus, including the islands of Amami-Ohshima, Okinawa, Kumejima, Ishigaki and Iriomote. Authors who recorded Helice from the Ryukyu Islands are almost certainly referring to the new species instead (Table 1), although we were not able to examine their material. Our sampling covered most of the Ryukyu Islands (from Amami to Iriomote), and all the specimens belong to the new species. Paratypes are designated to the specimens collected from Yaeyama Islands (including the islands of Ishigaki and Iriomote), as the other main localities, including the islands of Okinawa and Amami, are located relatively far from the type locality (> 300 km).


Ngan Kee Ng, Tohru Naruse and Hsi-Te Shih. 2018. Helice epicure, A New Species of Varunid Mud Crab (Brachyura, Decapoda, Grapsoidea) from the Ryukyus, Japan. Zool Stud. 57:15. doi:10.6620/ZS.2018.57-15
http://zoolstud.sinica.edu.tw/Journals/57/57-12.pdf

Wednesday, March 27, 2024

[Crustacea • 2024] Caligoplagusia okinawa • A New Genus and Species of A Submarine Cave Crab of the Family Plagusiidae Dana, 1851 (Brachyura: Grapsoidea) from Okinawa Island, Ryukyu Islands, southwestern Japan

  

Caligoplagusia okinawa 
Fujita & Naruse, 2024
 
ヨミノショウジンガニ  ||  DOI: 10.11646/zootaxa.5410.3.8
 
Abstract
Caligoplagusia okinawa n. gen. & n. sp., assigned to the brachyuran family Plagusiidae Dana, 1851 is described on the basis of a male and a female specimens collected from a semi-submerged marine cave on the limestone shore of Okinawa Island, Ryukyu Islands, southwestern Japan. The new monotypic genus is most similar to Euchirograpsus H. Milne Edwards, 1853 and Miersiograpsus Türkay, 1978 in that the frontal margin lacks a deep sublateral cleft adjacent to the orbit, but differs significantly by its subhexagonal carapace shape, the anterolateral margin of the carapace with three teeth including the external orbital tooth, the anterior margin of ambulatory meri each armed with a row of large teeth, and the greatly reduced eyes. The pale body colour, reduced eyes, the very elongate antennal flagellum, and long ambulatory legs are all typical brachyuran adaptations to living in cave environments. This is the first cave-dwelling species of the family Plagusiidae.

Crustacea, Thoracotremata, anchialine, dark environment, cryptic fauna

 
Caligoplagusia okinawa n. gen. & n. sp.
 「ヨミノショウジンガニ」


 Yoshihisa Fujita and Tohru Naruse. 2024. A New Genus and Species of A Submarine Cave Crab of the Family Plagusiidae Dana, 1851 (Crustacea: Brachyura: Grapsoidea) from Okinawa Island, Ryukyu Islands, southwestern Japan.  Zootaxa. 5410(3); 408-418. DOI: 10.11646/zootaxa.5410.3.8
Researchgate.net/publication/378179989_A_new_genus_and_species_of_a_submarine_cave_crab_of_the_family_Plagusiidae_from_Okinawa_Ryukyu_Islands_SW_Japan

Sunday, March 10, 2024

[Paleontology • 2024] Pseudocarcinus karlraubenheimeri • A New ‘Southern Giant Crab’ from A Miocene continental slope palaeoenvironment at Taranaki, North Island, New Zealand


Pseudocarcinus karlraubenheimeri 
van Bake & Ossó, 2024

Photographs by Jean-Claude Stahl (NMNZ)

ABSTRACT
Large-sized extinct crab specimens recovered from Waitoetoe beach, North Island, New Zealand form the basis for a new species of ‘Southern Giant Crab’, Pseudocarcinus karlraubenheimeri n. sp. The specimens originate from the upper Miocene Urenui Formation (approximately 8.8 myr) of the Taranaki Basin, in which a series of volcanoes of the Mohakatino Volcanic Centre erupted offshore, leading to the formation of a specific palaeoenvironment. The well-preserved, articulated specimens were found buried in sediments which include reworked volcanogenic material. The crabs inhabited a deep-marine setting. This is the first evidence that Pseudocarcinus inhabited the region that is now New Zealand. New Zealand Miocene environments apparently offered favourable conditions in terms of food sources, metabolic requirements, and calcium-carbonate supply for Pseudocarcinus karlraubenheimeri n. sp. Pseudocarcinus thrived on both sides of the Tasman Sea until it disappeared in New Zealand waters. Pseudocarcinus crabs are characterised by gigantism, which provided them with significant advantages in competition and defence. Their carnivorous nature is reflected in their exceptionally large major cheliped. The broader use of benthic dwelling gastropods and bivalves as prey seems to have led to subsequent advances in brachyuran claw engineering, and an increase of molluscivorous crabs in the Late Cretaceous and Palaeogene.

KEYWORDS: Brachyura, Pseudocarcinidae, new species, Taranaki Basin, Urenui Formation, volcanic deposits

Pseudocarcinus karlraubenheimeri n. sp.,
A, holotype, NMNZ CR.027704, showing dorsal carapace, thoracic sternum and major right cheliped (male); B, detail of right major cheliped and thoracic sternum; B’, annotated detail of thoracic sternum, abbreviations: 4, 5, 6, thoracic sternites 4, 5 and 6; e4, e5, e6, episternites 4, 5 and 6; g4, g5, gynglyme of thoracic sternites 4 and 5; 4/5, 5/6, thoracic sternal sutures 4/5 and 5/6; ag, axial groove; og, oblique groove; pb, press-button for pleonal holding mechanism.
Photographs by Jean-Claude Stahl (NMNZ). Scale bars equal 50 mm.

 Pseudocarcinus karlraubenheimeri n. sp.

Etymology. In honour of Karl Raubenheimer (New Plymouth, North Island, New Zealand), who collected and donated the holotype specimen described in the present study.


Barry W. M. van Bake and Àlex Ossó. 2024. A New ‘Southern Giant Crab’ from A Miocene continental slope palaeoenvironment at Taranaki, North Island, New Zealand. New Zealand Journal of Geology and Geophysics. DOI: 10.1080/00288306.2024.2314472  

Sunday, March 3, 2024

[Crustacea • 2024] Lepidothelphusa menneri (Brachyura: Gecarcinucidae) • First Record of the Genus from Kalimantan, Indonesia


Lepidothelphusa menneri 
Ng & Wowor. 2024 
 
Abstract
The gecarcinucid freshwater crab genus, Lepidothelphusa Colosi, 1920, is known only from Sarawak in northern Borneo, with six recognised species i.e. Lepidothelphusa cognettii (Nobili, 1903); L. flavochela Grinang & Ng, 2015; L. limau Grinang & Ng, 2015; L. loi Grinang & Ng, 2015; L. padawan Grinang & Ng, 2015; and L. sangon Grinang & Ng, 2015. The genus is now reported from Indonesian Borneo for the first time, from specimens recently collected from Gunung Kelam in Sintang Regency, Kalimantan Barat Province. Lepidothelphusa menneri n. sp. has a very distinctive tri-coloured pattern in life, unique among congeners. It can also easily be separated from congeners by carapace, epistome, male pleonal and male first gonopod characters.

Crustacea, taxonomy, Gecarcincoidea, new taxon, freshwater crab, western Borneo, Southeast Asia.




Peter K. L. Ng and Daisy Wowor. 2024. Lepidothelphusa menneri n. sp. (Crustacea: Brachyura: Gecarcinucidae), First Record of the Genus from Kalimantan, Indonesia. Zootaxa. 5397(2); 218-224. DOI: 10.11646/zootaxa.5397.2.3
 Researchgate.net/publication/377151155_Lepidothelphusa_menneri_n_sp__first_record_of_the_genus_from_Kalimantan_Indonesia

Monday, January 8, 2024

[Crustacea • 2024] Garymunida namora, Trapezionida macilenta, T. pulex, etc. • DNA Barcoding and Morphology revealed the Existence of Seven New Species of Squat Lobsters in the Family Munididae (Decapoda: Galatheoidea) in the southwestern Pacific


A Trapezionida macilenta sp. nov., male holotype, Papua-New Guinea
B Trapezionida pulex sp. nov., ovigerous female paratype, New Caledonia.

Macpherson, Rodríguez-Flores & Machordom, 2024
 
Abstract
Specimens of squat lobsters belonging to the family Munididae Ahyong et al., 2010, representing the genera Garymunida Macpherson & Baba, 2022, Trapezionida Macpherson & Baba, 2022 and Typhlonida Macpherson & Baba, 2022, were collected during several cruises around New Caledonia and Papua New Guinea, Southwest Pacific. The integrative study of these specimens revealed the presence of one new species in Garymunida, five in Trapezionida and one in Typhlonida. We describe and illustrate these new species, providing some new data on the taxonomy of several rare or scarcely studied species of Trapezionida. Molecular data from different markers (mitochondrial and nuclear) was also included, based on data availability, to support the taxonomic status of different species. Finally, a key to species for each genus is also provided.

Key words: Crustacea, integrative taxonomy, molecular characters, morphology, Pacific Ocean


Superfamily Galatheoidea Samouelle, 1819
Family Munididae Ahyong, Baba, Macpherson & Poore, 2010

Genus Garymunida Macpherson & Baba, 2022 in Machordom et al. 2022

 Garymunida namora sp. nov.

Etymology: "Namora" is a mythological woman participating in the creation of New Guinea. Used as noun in apposition.


Genus Trapezionida Macpherson & Baba, 2022 in Machordom et al. 2022

 Trapezionida brachytes (Macpherson, 1994)

 Trapezionida leptitis (Macpherson, 1994)

 Trapezionida brevitas sp. nov.

Etymology: From the Latin, brevitas, shortness, in reference to the small size of the species.

 Trapezionida diluta sp. nov.

Etymology: From the Latin, dilutus, thin, in reference to the shape of the antennular peduncle.

Colour in life A Trapezionida macilenta sp. nov., male holotype, 5.7 mm (MNHN-IU-2013-1094), Papua-New Guinea
B Trapezionida pulex sp. nov., ovigerous female paratype, 4.4 mm (MNHN-IU-2013-1882), New Caledonia.

 Trapezionida macilenta sp. nov.

Etymology: From the Latin, macilentus, thin, in reference to the long and slender antennular peduncle.

 Trapezionida microtes sp. nov.

Etymology: From the Greek, mikrossmall, in reference to the small size of the species.


 Trapezionida pulex sp. nov.

Etymology: From the Latin, pulexflea, in reference to the small size of the species.


Genus Typhlonida Macpherson & Baba, 2022 in Machordom et al. 2022

 Typhlonida eluminata sp. nov.

Etymology: From the Latin, eluminatus, blinded, in reference to the small eyes.


Enrique Macpherson, Paula C. Rodríguez-Flores and Annie Machordom. 2024. DNA Barcoding and Morphology revealed the Existence of Seven New Species of Squat Lobsters in the Family Munididae (Decapoda, Galatheoidea) in the southwestern Pacific. ZooKeys. 1188: 91-123. DOI: 10.3897/zookeys.1188.114984