Uca (Petruca), a new subgenus for the rock fiddler crab Uca panamensis <br />(Stimpson, 1859) from Central America, with comments on some species of the American broad-fronted subgenera

Abstract

Among the fiddler crabs from the Americas, Uca panamensis (Stimpson, 1859) (Crustacea: Decapoda: Ocypodidae) is unusual in its behavior and ecology, living in stony habitats rather than sandy or muddy substrates. This species also has several unusual morphological characters of the carapace and major and minor chelae, and had been placed in either the subgenera Minuca Bott, 1954, or Leptuca Bott, 1973. The armature at the inner corner of the orbital floor, as well as the morphology of the urocardiac ossicles of the gastric mill of U. panamensis, are, however, plesiomorphic characters, and are closer to the condition in species belonging the subgenera Uca and Afruca. Phylogenetic relationships, based on mitochondrial 16S rDNA and cytochrome oxidase subunit I, and nuclear 28S rDNA, supported by its unusual morphological features indicate that this species belongs to its own subgenus. A new subgenus Uca (Petruca) subgen. nov. is herein established for U. panamensis. In addition, the status of Uca thayeri Rathbun, 1900, U. umbratila Crane, 1941, U. virens Salmon & Atsaides, 1968, and U. longisignalis Salmon & Atsaides, 1968, are revised and discussed based on a reappraisal of their phylogenetic relationships.

Constraints on geographic variation in fiddler crabs (Ocypodidae: Uca) from the western Atlantic

“…The analysis of Shih et al . () represents the most comprehensive molecular phylogenetic tree to date and includes all of the species analysed herein. Shih et al .…”

“…Shih et al . () estimated divergence times on some nodes by applying a substitution rate for combined 16S and COI of marine sesarmids (brachyurans belonging to a superfamily closely related to that containing Uca ) to the p‐distance between clades. By their estimates, the subgenera Minuca and Leptuca diverged around 9 million years ago.…”

“…A Bayesian inference phylogenetic tree was obtained from Shih et al . (). This tree is based on mitochondrial 16S rDNA, cytochrome oxidase subunit I (COI), and nuclear 28S rDNA from 55 species representing 12 subgenera.…”

“…We used phylogenetic independent contrasts (PIC, Felsenstein, 1985;Paradis et al, 2004) in order to compare the within-and among-population covariation properties across species. A Bayesian inference phylogenetic tree was obtained from Shih et al (2015). This tree is based on mitochondrial 16S rDNA, cytochrome oxidase subunit I (COI), and nuclear 28S rDNA from 55 species representing 12 subgenera.…”

“…This tree is based on mitochondrial 16S rDNA, cytochrome oxidase subunit I (COI), and nuclear 28S rDNA from 55 species representing 12 subgenera. The analysis of Shih et al (2015) represents the most comprehensive molecular phylogenetic tree to date and includes all of the species analysed herein. Shih et al (2015) estimated divergence times on some nodes by applying a substitution rate for combined 16S and COI of marine sesarmids (brachyurans belonging to a superfamily closely related to that containing Uca) to the p-distance between clades.…”