Surveys of Afrotemperate forests yields two new freshwater crabs (Decapoda: Potamonautidae: Potamonautes MacLeay, 1838) from South Africa

Sampling of remote inland aquatic habitats in South Africa has constantly been yielding novel endemic freshwater crab species (Potamonautes MacLeay,1838). During the present study, we report on the discovery and description of two new freshwater crab species (Potamonautes baziya sp. nov., and P. mariepskoppie sp. nov.) from Afrotemperate forested mountain regions in the Eastern Cape and Mpumalanga provinces of South Africa, respectively. Phylogenetic evidence derived from DNA sequence data of three partial mitochondrial loci (12S rRNA, 16S rRNA and cytochrome oxidase subunit one, COI) corroborates the evolutionary distinction of the two novel species. In addition, morphological and ecological data for the two new species further delineate their evolutionary distinction from congeneric sister species. A comparison of the taxonomically important gonopods 1 and 2 and carapace features among the sister species and other known freshwater crabs of South Africa was further used to provide evidence for the distinction of the two novel species. The discovery of two new species suggest that remote mountainous areas or unsampled regions in South Africa likely harbor several novel species, reiterating a call to document aquatic inland biodiversity in forested and mountainous regions of the country.

Freshwater crabs could act as vehicles of spreading avian influenza virus

Avian influenza virus (AIV) possessed significant risk to various animals and human health. Wild birds, especially waterfowls are considered to be the natural reservoir of AIVs. The ecology of AIV is still far from being fully understood. Freshwater crabs are nonnegligible biotic factor in AIV ecosystem. We analyzed the ability of freshwater crabs accumulate and spread AIV. We found that AIV remain infectious in water only for 36 h but persist in crabs for 48 h. Crabs could accumulate AIV in their gills and gastrointestinal tracts. The AIV titers in crabs were higher than the surrounding contaminated water. Crabs could accumulate AIV from contaminated water, carry the virus and spread to naïve crabs via surrounding water. Our study identified freshwater crab as a novel transmission vehicle in AIV ecosystem.

First record of a freshwater crab, Maydelliathelphusa masoniana (Henderson, 1893) (Decapoda: Brachyura: Gecarcinucidae) from West Bengal, India

The genus Maydelliathelphusa Bott, 1969 includes five species, M. masoniana (Henderson, 1893), M. edentula (Alcock, 1909), M. falcidigitis (Alcock, 1910), M. harpax (Alcock, 1909), and M. lugubris (Wood-Mason, 1871), and is endemic to India. Out of the five species, only Maydelliathelphusa lugubris (Wood-Mason, 1871) was reported from West Bengal previously. Present study reports the second species, M. masoniana (Henderson, 1893), from West Bengal, India for the first time.

A freshwater crab (Barytelphusa sp.) feeding on a catfish (Pterocryptis sp.)

The freshwater crab, Barytelphusa cunicularis (Westwood, 1836), is a common and widespread crustacean species inhabiting freshwater streams throughout India except the northeast. It is an omnivore that feeds on small crustaceans, gastropods, insects and aquatic vegetation. This species is commonly collected as a food commodity and is also often reared in captivity for the same purpose. In captivity, these crabs seem to prefer animal-based food and are generally fed about 10% of their total biomass in prawn and rice flakes daily. Observations of B. cunicularis feeding in nature are scant in the literature, and to the best of my knowledge there have not been any reports of the species feeding on fish. Herein I report the first observation of B. cunicularis feeding on a Malabar silurus, Pterocryptis wynaadensis, a type of catfish.

Geothelphusa boreas, a new montane freshwater crab (Crustacea: Potamidae: Geothelphusa) from northeastern Taiwan, and the identity of G. hirsuta Tan & Liu, 1998

A new freshwater crab is described from the montane area in northeastern Taiwan based on morphological and molecular evidence. Geothelphusa boreas sp. nov., from the Fushan Botanical Garden situated around New Taipei City and Yilan County, is distinct from similar congeners by the structure of the male first gonopod and the proportions of the male thoracic sternites. In addition, after comparing the holotypes of G. takuan and G. hirsuta Tan & Liu, 1998, no substantial difference could be found. Molecular evidence from mitochondrial cytochrome oxidase subunit I also supports the recognition of the new species and the conspecificity of G. hirsuta with G. takuan.

A new species of freshwater crab of the genus Nanhaipotamon Bott, 1968 (Crustacea, Decapoda, Brachyura, Potamidae) from Longhai, Fujian Province, China

A new species of freshwater crab of the genus Nanhaipotamon Bott, 1968 is described from Xiaye Village, Chengxiang Town, Longhai County, Zhangzhou City, Fujian Province, China. The new species is distinguished from congeners by the combination of characters of its carapace, third maxilliped, unequal chelipeds, triangular male abdomen and unique male first gonopod. Molecular evidence derived from partial mitochondrial 16S rRNA and COI genes also support the species as new.

A new species of freshwater crab of the genus Teretamon Yeo & Ng, 2007 (Decapoda, Brachyura, Potamidae) from southwestern Yunnan, China

A new species of freshwater crab of the genus Teretamon Yeo & Ng, 2007, Teretamon husicum sp. nov., is described here from Husa Town, Longchuan County, Dehong Prefecture, Yunnan Province, China. Teretamon husicum sp. nov. can be distinguished from other species by a suite of morphological characters, including a bilobed frontal margin, smooth posterolateral regions, and a broadly rounded dorsal flap on the G1 terminal segment. An updated identification key for the species of the genus Teretamon is provided.