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A new species of the freshwater shrimp of the genus Macrobrachium irwini sp. nov., is described from the Nandhini River near Kateel, Karnataka region of Western Ghats, India. 11 specimens of Macrobrachium irwini sp. nov. were collected from Nandhini river running through a secondary forest with heavily vegetated banks. The morphological analyses revealed that the new species can be clearly distinguished from the closely related species, M. snpurii and M. scabriculum based on the shape and dentition on rostrum, antennular peduncle, segmental ratios of first pereiopod, tubercles along the cutting edges of immovable and movable fingers of second major pereiopod and telson. Additionally, we provided the striking colour patterns on the new species which could be distinguish this species from congeneric species.

A new species of Diplophryxus Richardson, 1904 is described from shallow waters of Chile infesting Alpheus inca Wicksten & Méndez G., 1981. This is the ninth species described in the genus. Diplophryxus richardsonae Chopra, 1930 from India does not belong in the genus and a new genus, Micropodiphryxus, is erected for it. Diplophryxus is now known to have a circumglobal distribution in temperate and tropical latitudes infesting host shrimp in Alpheidae, Palaemonidae, and Gnathophyllidae, whereas the new genus is known only from the Andaman Islands and Kerala, India, from hosts in Crangonidae. A key to species of both genera is provided along with a summary of all records from the literature. [ABSTRACT FROM AUTHOR]

Macrobrachium madhusoodani new species is described from the upper reaches of Ithikkara River, Kerala, South India. The species shares certain characters with M. scabriculum (Heller, 1862), M. aemulum (Nobili, 1906), and M. nobilii (Henderson & Matthai, 1910) in the number and arrangement of rostral teeth, while it differs remarkably from those three species in distinctive diagnostic characters: rostral formula 10-14/2-3 with 5-6 postorbital teeth; carapace smooth with distal end of rostrum straight; chelae with 4 denticles in the movable and 3 in the immovable finger, in the proximal part of the cutting edge; the distal part of the fingers of the second chelate legs are darkly pigmented except the tip. Three prominent pigment spots are found midlaterally on the last three abdominal somites, with prominent pigmentation at the tip of the telson. [ABSTRACT FROM AUTHOR]

Three new species of Macrobrachium Bate, 1868, i.e., M. gurudeve, M. jayasreei, and M. kunjuramani, collected from the rivers Kabbini and Bhavani (east flowing rivers of Kerala State) are described here in detail. The most important diagnostic features of the species are: in M. gurudeve, the rostrum is broad with 7-9 upper (2 post-orbital) and 3-5 ventral teeth, characteristically arranged; telson broad, dorsal pairs of spines situated at the distal third, and inner distal pair of spines very short; 2nd cheliped with carpus shorter than chela, and fingers ¾ of palm; appendix masculina with 1 long and 4 short distal spinous setae and 13 and 4 stiff lateral setae in two rows; uropodal exopod without accessory spine. In M. jayasreei, the rostrum is very slender, with 7-8 (1 or 2 post-orbital) and 4-5 ventral teeth, maximum width of the rostrum at the level of 2nd ventral tooth, and distal ventral tooth widely separated from the remaining ones; telson slender with 2 pairs of dorsal spines at distal half, and inner distal pair very long and slender; 2nd pair of pereiopods with carpus longer than chela and fingers about half as long as palm, as well as palm longer than half carpus; appendix masculina with 6 distal, stiff spinous and 9 lateral stiff setae, uropodal exopod without accessory spines. In M. kunjuramani, rostrum broad with 7-9 (2 post-orbital) dorsal and 4-5 ventral teeth, characteristically arranged; cephalothorax shorter than rostrum; telson slender with dorsal spines situated at the distal half, and inner distal pair of spines slender; 2nd pereiopods with carpus longer than chela, fingers half as long as palm; appendix masculina with 3 distal, stiff spinous and 6 lateral stiff setae; uropodal exopod with accessory spine. The colouration of the three species is also described. [ABSTRACT FROM AUTHOR]

A preliminary study on humoral defence factors of Indian river prawn, Macrobrachium malcolmsonii was carried out. The serum of animals collected from intermoult stage had an average total protein content of 9.65 g dl-1 and lysozyme-like activity of 0.04 unit ml-1. The phenoloxidase activity in haemocyte lysate supernatant was triggered significantly (P<0.05) by chitosan, Gram-positive and Gram-negative bacterial cells in comparison to other elicitors viz., levamisole, trypsin and glucan. The serum contained an agglutinin against Gram-negative bacteria and a haemagglutinin against a wide range of vertebrate erythrocytes. The haemagglutinin was stable over a wide range of pH (3.0–7.0) and temperatures (-30 °C to 60 °C). A 413 kDa N-acetyl galactosamine-specific haemagglutinin was purified by single step affinity chromatography and the protein was found to be calcium ion-dependent in nature and made up of five different subunits of varied molecular weights on denaturing SDS-PAGE. [Copyright &y& Elsevier]

The cleaning rock pool shrimp commonly inhabit the shallow waters of reef and crevices regions at 0.5-3.0 m depth. Recent exploration conducted off the Gulf of Mannar and Agatti Island yielded the species, Urocaridella antonbruunii (Bruce, 1967) from the bottom curve of the coral boulder at a depth of 0.5-1.0 m. This is the new record for the Gulf of Mannar and Lakshadweep waters. Major distinguishing morphological characters of the congener's were described and illustrated. The molecular analysis confirmed the species occurrence in Indian waters followed the intraspecific and interspecific genetic divergences (16S gene) were estimated between 0.3-2.1% for within species and 6.4-11.2% for between species respectively. Additionally, we updated and provided the illustrative key characters for all members of the genus Urocaridella.

A new species of the genus Urocaridella Borradaile, 1915, Urocaridella arabianensis n. sp. is described and illustrated based on fifty-five specimens collected from the reef regions of Agatti Island, Lakshadweep, Arabian Sea. Urocaridella arabianensis n. sp. is morphologically close to U. pulchella Yokes Galil, 2006, reported from the Mediterranean Sea. However, the present specimen is clearly distinguished with its rostrum length, which is 1.7 to 2.1 times as long as carapace, 10 ventral rostral teeth, carpus of 1st pereopod is 2.5 times long as palm, carpus of 2nd pereopod is 1.8 times as long as palm, presence of a spine in latero-middle of the fourth and fifth abdomens and the sixth abdominal segment is 2.3 times long as the fifth segment. Partial segment of the mitochondrial COI, 16S rRNA and nuclear gene 18S rRNA and H3 indicates that the new species is sister to a clade comprising of U. pulchella, U. antonbruunii and U. degravei. The pair wise genetic distance of COI showed great distance with the closest congeneric species.

The recent collection of Palaemonid shrimps from Agatti Island, Lakshadweep, Arabian Sea, have provided further additions to the Indian marine fauna. In the manuscript, a new species, Periclimenella agattii sp. nov. is described and illustrated. The new species is morphologically most similar to P. spinifera among other congeners, but it strongly differs from that species by having upper the antennular flagellum with 14-16 segments, short free ramus with 12-13 segments, lower antennal flagellum thin and bearing 35-37 segments; 4 minute lateral spines on basal segment of 3rd maxilliped; male palm:carpus ratio of second pereopod higher than in female, propodus of 3rd pereopod with 7-8 ventral spines and hepatic spine with groove. Genetic analysis using the mitochondrial COI and 16S rRNA genes sequences proved that, the new species is significantly distinct from the closed related species.

It is important to understand nutrient budgets of aquaculture practices for efficiency of input resources and to utilize all output nutrient sources. The aim of the present study was to develop a nutrient budget for giant freshwater prawn (Macrobrachium rosenbergii) culture ponds. The study was conducted in farmer's ponds (0.25-0.5 ha) of Odisha, India, and the results showed that feed accounted 97% total nitrogen (N), 98.7% total phosphorus (P) and 90% total organic carbon (OC), respectively. The harvested prawn accounted for recovery of 37% N, 10% P and 15% OC, respectively. The N, P and OC accumulated in sediment were 52%, 76%, and 65%, respectively. Nutrient loads in the effluents were 2.22 ± 0.66 kg inorganic N, 0.40 ± 0.15 kg P, and 21.01 ± 6.4 kg OC per ton of prawn production. The present study implicated that high nutrient values observed in both water and sediment provide important opportunities for nutrient reuse through pond sediment applications to croplands as an organic manure, as well as pond water irrigation to crops as a "liquid fertilizer".

The giant freshwater prawn, Macrobrachium rosenbergii, is facing increased threat due to disease as its culture becomes more widespread. A disease characterized by the swelling of the branchiostegal region and deformities of the appendages, named balloon disease by farmers, has caused considerable economic loss in the Nellore region of Andhra Pradesh, India. Clinical signs of diseased animals include a voluminous hypertrophy of some gill filaments and the inner area of the branchiostegite. By histology, hypertrophied areas at the level of the gill filaments or branchiostegite had an identical structure corresponding to a large cyst filled with a fluid containing a few free haemocytes, limited on one side by the cuticle and on the other by the subcuticular epithelial layer. Analysis of the diseased prawns did not reveal any pathogenic agent leading us to conclude that the disease is idiopathic, probably due to suboptimal water quality conditions.