Monday, June 22, 2015

[Crustacea • 2015] Uca (Xeruca), A New Subgenus for the Taiwanese Fiddler Crab Uca formosensis Rathbun, 1921 (Decapoda: Ocypodidae), based on morphological and molecular evidence


FIGURE 3. Uca formosensis, ♂ from Haishangu, Hsinchu, Taiwan (NCHUZOOL 13673, CW 27.9 mm),
A, dorsal view; B, frontal view showing the right major chela.
FIGURE 2. Uca formosensis. A, B, holotype (USNM 54472, CW 28.8 mm) recognized by Crane (1975);
E, ♀ from Haishangu, Hsinchu (NCHUZOOL 13849, CW 32.2 mm), showing the tuberculate swelling on carapace behind right dorsolateral margin (arrowed) (E) scale = 5 mm.
DOI: 10.11646/zootaxa.3974.2.1

Abstract
The fiddler crab Uca formosensis Rathbun, 1921 (Crustacea: Decapoda: Ocypodidae), restricted to the western part of Taiwan and the offshore Penghu (Pescadores) Islands in the Taiwan Strait, has been placed under the subgenus Uca (Gelasimus) Latreille, 1817 (= Uca (Thalassuca) Crane, 1975) based on only less than a dozen specimens, but later suggested under the subgenus Tubuca Bott, 1973 because the similarity of external morphology. A suite of characters of carapace, major cheliped, gastric mill, male first gonopod, and chela handedness, as well as the phylogenic relationships (mitochondrial 16S rDNA and cytochrome oxidase subunit I, and nuclear 28S rDNA), nevertheless support this species belongs to its own subgenus. A new subgenus Uca (Xeruca) subgen. nov. is herein established for U. formosensis.

Key words: Xeruca, new subgenus, Uca formosensis, fiddler crab, Ocypodidae, taxonomy, Taiwan, 16S rDNA, cytochrome oxidase subunit I, 28S rDNA


Systematic account

Family Ocypodidae Rafinesque, 1815
Subfamily Ocypodinae Rafinesque, 1815

Genus Uca Leach, 1814

Uca (Xeruca) subgen. nov.
Uca (Thalassuca) Crane, 1975: 75 (part); Rosenberg 2001: 840, 848, 851 (part).
Tubuca Bott, 1973: 322 (part).
Uca (Tubuca)—Beinlich & von Hagen 2006: 10, 14, 15, 25 (part); Ng et al. 2008: 241 (part).

Type species. Uca formosensis Rathbun, 1921, by present designation.
Etymology. From the Greek xeros for “dry,” for the high intertidal habitat of the type species, in arbitrary combination with the genus name Uca. Gender feminine.


Shih, Hsi-te. 2015. Uca (Xeruca), A New Subgenus for the Taiwanese Fiddler Crab Uca formosensis Rathbun, 1921 (Crustacea: Decapoda: Ocypodidae), based on morphological and molecular evidence. Zootaxa 3974(2): 151–169. DOI: 10.11646/zootaxa.3974.2.1