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