Sanjeevi Prakash

A new species of Lysmata Risso, 1816 (Crustacea, Decapoda, Lysmatidae) from the Gulf of Mexico

A new species of peppermint shrimp, Lysmata baueri n. sp., is described based on a single specimen from the eastern Gulf of Mexico. The new species can be distinguished from other morphologically similar species of Lysmata Risso, 1816 by the number of teeth, length and shape of the rostrum, the length of the antennular peduncle relative to the scaphocerite, the number of meral and ischial articles in the second pereiopods, and the number of spines on the flexor margin of the dactyli from the third to fifth pereiopods. Morphological characters demonstrate that L. baueri n. sp., is most closely related to the eastern Pacific L. californica (Stimpson, 1866), L. nayaritensis Wicksten, 2000 and L. porteri (Rathbun, 1907).

Reproductive morphology and mating behaviour in the hingebeak shrimp Rhynchocinetes durbanensis Gordon, 1936 (Decapoda: Caridea: Rhynchocinetidae) in India

The present study tests hypotheses about sexual dimorphism in body size and morphology versus differential mating behaviours of three male ontogenetic stages (typus, intermedius and robustus morphotypes) of the hingebeak shrimp Rhynchocinetes durbanensis Gordon using canonical discriminant analysis. There is strong sexual dimorphism in this species, in that robustus morphotypes are greater in size and with larger appendages (extended third maxillipeds and major [first] chelipeds) than females. As typus males grow bigger in size, their third maxillipeds and major chelipeds become proportionately larger than those of females, and the numbers of corneous spines on the terminal segment of the maxillipeds are reduced. Although there is no sexual dimorphism in body size between typus and intermedius males and females, the robustus males are often substantially larger than females. During mating and spermatophore transfer, all male morphotypes performed similar behaviours (touching, overlapping and holding), but only intermedius and robustus morphotypes appeared to fertilize the broods of the females successfully. Robustus males were faster in approaching as well as mating with receptive females than subordinate males. When mating with robustus males, females spawned more quickly than after mating with typus and intermedius males. Additionally, the time taken for spermatophore transfer by typus males was longer. Rejection by females during the initial approach by typus males often resulted in unsuccessful spermatophore attachment. Results of this study suggest a dominance hierarchy in R. durbanensis similar to certain other rhynchocinetid species in which females appear to prefer mating with the larger robustus males.

New records of marine ornamental shrimps (Decapoda: Stenopodidea and Caridea) from the Gulf of Mannar, Tamil Nadu, India

Marine ornamental shrimps found in tropical coral reef waters are widely recognized for the aquarium trade. Our survey of ornamental shrimps in the Gulf of Mannar, Tamil Nadu (India) has found three species, which we identify as Stenopus hispidus Olivier, 1811, Lysmata debelius Bruce, 1983, and L. amboinensis De Man, 1888, based on morphology and color pattern. These shrimps are recorded for the first time in Gulf of Mannar, Tamil Nadu. Detailed information, including the description of specimens, habitat and distribution, is provided.

Breeding and Rearing of Marine Ornamentals

The marine aquarium trade is a billion dollar business that may sustain continued growth in the coming years. In the past decade, there has been a worldwide increase in the popularity of reef tanks, which has led to an increased demand for marine ornamental organisms (Wood 2001; Green 2003). In contrast to the freshwater ornamental species, most marine organisms being marketed in the aquarium trade are collected from the wild, particularly from coral reef areas. The prevalence of destructive low-cost harvesting techniques, such as the use of cyanide and explosives, has caused dramatic and drastic impacts on the health and biodiversity of the reef ecosystems. Developing hatchery technology for marine ornamental species is therefore urgently needed to guarantee the sustainable supply for the industry while minimising the negative impacts on the natural environment (Lin et al. 2002). In the recent years, researchers, traders, collectors and hobbyists have begun a worldwide effort to minimise the growing pressure on the natural populations of marine ornamental species and to promote the sustainable use of these high-valued resources (Corbin 2001).

Checklist of the Porcellanidae (Crustacea: Decapoda: Anomura) of India

Although the porcellanid fauna of Indian waters has been studied for more than 150 years, diversity of this family remains underestimated. In order to complement the knowledge on the porcellanid fauna of India, an annotated checklist is herein provided on the basis of published literature. A total of 30 species belonging to 11 genera are currently known from Indian waters. The distribution ranges of two porcellanids Porcellanella haigae and Pseudoporcellanella manoliensis indicate that they are endemic, as they are, so far, known only from their type locality (Gulf of Mannar, Tamilnadu). The list is arranged alphabetically by genus and species with information on species’ distribution and ecology.

First records of four species of Petrolisthes (Decapoda: Anomura: Porcellanidae) in Lakshadweep, India

Four porcellanid species, Petrolisthes coccineus (Owen, 1839), P. lamarckii (Leach, 1820), P. moluccensis (De Man, 1888) and P. tomentosus (Dana, 1852), are reported on the basis of specimens collected from an intertidal area of Agatti Island, Lakshadweep Archipelago in south-western India. All the four species are recorded from the archipelago for the first time, and P. moluccensis is new to the Indian fauna. Morphological diagnoses, notes on the habitats and distributions are provided for the four species.

DNA Barcoding of Sharp Tail Sunfish Masturus lanceolatus Lienard, 1840 (Tetraodontiformes: Molidae)

Detailed analyses on morphometry (expressed as % standard length and % head length), meristic characters and mitochondrial barcode region sequence of the sharp tail sunfish Masturus lanceolatus Lienard, 1840 have made to confirm the species identity. Further, investigations on phylogenetic relationships between species of the Molidae family have been taken into consideration by constructing neighbor-joining tree to fulfill the gaps on taxonomical validation and their biological information.

Occurrence of Urchin Crab Echinoecus pentagonus A. Milne Edwards, 1879 (Decapoda, Brachyura, Eumedonidae) in Lakshadweep, India

Sea urchin crab Echinoecus pentagonus A. Milne Edwards was documented based on specimen collected from the intertidal region of Agatti Island, Lakshadweep. It was found clinging on the ventral side of the sea urchin host Echinothrix calamaris Pallas. Species identification was confirmed with the help of elongated rostrum and carapace morphology. E. pentagonus found in Lakshadweep constitutes the known geographical range extension. In the present paper, description of species, host and distribution were discussed in detail.