A new species of palaemonid prawn Macrobrachium ramae sp.nov. (Malacostraca:Decapoda:Palaemonidae) from Rupnarayana River, West Bengal, India with its molecular profiles

A new species Macrobrachium ramae is described from Rupnarayana river, West Bengal, India along with its molecular characterization and Scanning electron microscopy. The species shares certain characters with M.gurudeve, M.jayasreei, M.kunjuramani and M.saengphani but differs remarkably from these species in the structure and shape of rostrum, telson, appendix masculina and in the size of the proximal segment of the antennular peduncle. Molecular characterization and phylogenetic analysis of M.ramae with mitochondrial COI and 16S rRNA genes reinforce the morphological conclusion and supports the view that it is a new species.

Integrative taxonomy uncovers a new stygobiotic Caridina species (Decapoda, Caridea, Atyidae) from Guizhou Province, China

Collecting much-needed information on the taxonomy, distribution, and ecology of cave-dwelling shrimp is vital for addressing the urgent challenges in conservation biodiversity in fragile cave ecosystems. Caridina incolorsp. nov., a new atyid shrimp from an underground stream of Yaoshui Cave, Daqikong scenic area, Libo County, Guizhou Province, southwestern China is described based on morphology and DNA analysis (mitochondrial COI). Caridina incolorsp. nov. differs from epigean congeners by its smaller eyes which range from reduced to completely blind; colorless body and appendages; long stylocerite and sixth abdominal segment; and relatively large eggs. In comparison to other cave species, Caridina incolorsp. nov. presents a long rostrum and stylocerite; slender sixth abdominal segment; and unique shape of the appendix masculina. Data on the habitat, ecology, and levels of threat are provided and suggest that it should be categorized as Critically Endangered (CR) under the current IUCN criteria.

Utilizing integrative taxonomy uncovers a new stygobiotic Caridina species (Decapoda: Caridea: Atyidae) from Guizhou Province, China

Collecting much-needed information on the taxonomy, distribution, and ecology of cave-dwelling shrimp is the foundation for addressing urgent challenges in conservation biodiversity and these fragile ecosystems. Caridina unicolor sp. nov., a new atyid shrimp from an underground stream of Yaoshui Cave, Daqikong scenic area, Libo County, Guizhou Province, southwestern China is described based on morphology and DNA analysis (mitochondrial COI). Caridina unicolor sp. nov. differs from epigean congeners by the variable eye, ranging from reduced to blind; colorless body and appendages; the long stylocerite and sixth abdominal segment; and relatively large eggs. In comparison to other cave species, Caridina unicolor sp. nov. presents a long rostrum and stylocerite; the slender sixth abdominal segment; and the unique shape of appendix masculina. The data on the habitat, ecology, and the levels of threat are provided and suggest that it be categorized as Critically Endangered (CR).

Caridina sinanensis, a new species of stygobiotic atyid shrimp (Decapoda, Caridea, Atyidae) from a karst cave in the Guizhou Province, southwestern China

From a biodiversity survey of a subterranean habitat near Sinan County, Guizhou Province, southwestern China, a new atyid shrimp of the genus Caridina H. Milne Edwards, 1837, C. sinanensissp. nov. was discovered. The new species can be separated from other congeners based on a combination of characters including depigmentation in body and reduction of eyes, small pigment spot at the centre of the cornea, the shape of rostrum and the endopod of the 1st male pleopod, and the relatively longer appendix interna on the appendix masculina of the 2nd pleopod. Mitochondrial COI and 16S rRNA gene sequences also support the establishment of the new species. Information on the habitat, and the levels of threat are discussed to guide the conservation of C. sinanensissp. nov.

A new species of Bragasellus (Isopoda, Asellidae) from NW Spain, with a key to the known species of the genus

During a survey on the benthic invertebrates of the upper reaches of river Eo (Galicia, NW Spain), a dense population of epigean asellid isopods were detected in the source of the river. After examination, these specimens resulted to belong to a new species of the genus Bragasellus Henry & Magniez, 1968. The new species comes to fill a geographical gap between the two alleged ancestral areas of the genus and is characterized by its appendix masculina (male pleopod II endopod), which bears a short but distinct cylindrical cannula and lacks basal process. Other characteristic traits are uniform black pigmentation in live specimens, pereopod I dactylus shorter than the palm of the propodus, smooth (instead of plumose) texture of the marginal setae on male pleopod I exopod, and pleopod III exopod with a straight internal side. In this job, description of the new taxon is provided, as well as a key to all the known species belonging to the genus.

A new record and mitochondrial identification of Pentias thompsoni Collinge, 1916 (Isopoda, Valvifera, Idoteidae) from the Nanji Islands, China

Pentias thompsoni Collinge, 1916 is recorded for the first time from China. The male specimen is described firstly, including the micromorphological characters of penes and appendix masculina. The partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI) of the species are also provided for a molecular characterization.

Sexual maturity of the small shrimp Potimirim brasiliana Villalobos, 1959 (Crustacea, Atyidae), from the southeastern coast of Brazil

The shrimp Potimirim brasiliana plays an important role in streams along the Brazilian coast as it feeds on the organic debris from the surrounding ecosystem. We determined the morphological sexual maturity of P. brasiliana by means of relative growth. Monthly throughout a year, we used sieves (2 mm mesh diameter) to collect the specimens in a coastal stream. A total of 3,521 specimens had their carapace length (CL) measured, as well as their second pleura length (PL) and the length (AML) and width (AMW) of the appendix masculina. The studied relationships were the following: CL vs. PL; CL vs. AML and CL vs. AMW, with the data adjusted to a logistic equation. All the relationships tested among the demographic groups differed statistically. The CL50 of females measured 3.45 mm, while the CL50 of males measured 2.75 mm. Two adult morphological groups were set apart for each sex. The CL vs. AMW relationship is the best at demonstrating the separation of the morphological groups for males. This fact is an intriguint issue as it suggests the presence of morphotypes in males, probably, playing different roles in the reproductive process.

A remarkable burrow-dwelling alpheid shrimp, new genus and new species, from the tropical eastern Pacific (Malacostraca: Decapoda: Caridea)

A new alpheid shrimp genus, Pachelpheus gen. nov., is established to accommodate Pachelpheus pachyacanthus sp. nov., described based on two specimens from the Las Perlas Archipelago, Pacific coast of Panama. Pachelpheus pachyacanthus sp. nov. appears to be an obligate symbiont dwelling in burrows of yet unknown infaunal hosts, on shallow near-shore subtidal sand flats. The main morphological characters of Pachelpheus gen. nov. are: (1) frontal margin of carapace with broadly rounded rostral projection, without orbital teeth; (2) sixth pleonite with articulated plate; (3) telson with two pairs of cuspidate setae dorsally, without anal tubercles; (4) eyes concealed in dorsal view, partly visible in lateral view; (5) chelipeds equal in size, symmetrical in shape, moderately enlarged, stout, carried extended; (6) cheliped carpus without rows of setae mesially; (7) cheliped fingers without snapping mechanism, each finger armed with one stout tooth; (8) second pereiopod carpus with five sub-articles; (9) third, fourth and fifth pereiopods with ischia armed with single robust cuspidate seta, meri armed with one to several unusually robust cuspidate setae; (10) second pleopod with appendix masculina in males only; (11) uropodal exopod and endopod with rows of slender spiniform setae on their distal margins; (12) uropodal diaeresis unusually thickened laterally, with two very stout spiniform setae; and (13) lateral lobe of the uropodal protopod rounded. The new genus appears to be morphologically most similar to Jengalpheops Anker & Dworschak, 2007 and Leslibetaeus Anker, Poddoubtchenko & Wehrtmann, 2006.

A new interstitial species of the genus Caecianiropsis Menzies & Pettit, 1956 (Isopoda, Asellota) from Korea

A new interstitial species, Caecianiropsisgoseongensissp. n. is described from littoral off the east coast of Korea (Sea of Japan). The species can be distinguished from its congeners by the number of antennular articles, shape of the male appendix masculina, setation of pereopods, and length ratio of the uropodal rami. To aid species identification a taxonomic key to all species of Caecianiropsis Menzies & Pettit, 1956 is also provided as well as a partial 16S mitochondrial ribosome RNA of the new species, which is the first genetic information for the genus.

Caridean prawn (Crustacea, Decapoda) with description of a new species and an invasive crayfish from Yuelu mountain national park, Hunan, China

Yuelu mountain national park (5A scenic area) is a rare urban mountain scenic area. The major impacts from human activity are growing, such as largely unplanned tourist activity, urbanization, and accelerated the others responsible for environmental changes. It is unavoidable to have great pressure and influence on the diversity of fauna on the scenic area. In order to better understand the diversity of the decapod fauna in the Yuelu mountain national park, an intensive field survey has been carried out. A total of five species was collected, three species of atyid shrimps, Neocaridina palmata (Shen, 1948), N. yueluensis, new species, and Paracaridina longispina (Guo & He, 1992), one species of palaemonid prawn, Macrobrachium nipponense (De Haan,1849), and an invasive crayfish, Procambarus clarkii (Girard, 1852). N. yueluensis is distiguished from congeners by the shorter rostrum, the stout carpus of first pereiopod and the stout chela of second pereiopod, not sexual dimorphism of the third and fourth pereiopods, the long appendix interna and arising from the inner border of appendix masculina, and the narrower scaphocerite.