Distribution and size of the Pacific deep water lobsterette, Nephropsis occidentalis Faxon, 1893 (Decapoda, Astacidea, Nephropidae) in the S.E. Gulf of California, Mexico
Por:
Hendrickx M.E.
Publicada:
1 ene 2003
Resumen:
The medium size Pacific lobsterette, Nephropsis occidentalis Faxon, 1893, is known from only a few records in the east Pacific (Gulf of California to Chile). A recent survey of deep-water benthic communities in the S.E. Gulf of California, Mexico, indicates that it is abundant at depths between 1050 and 1310 m and is tolerant to severe hypoxic conditions (0.38 to 1.4 ml O2/l, with six catches in less than 1 ml/l). Maximum individual size (135 mm, total length) and body weight (31.2 g) are relatively low compared to shallow water commercial shrimps fished in the region, but the species represents a potential by-catch fishery of the pandalid shrimps Heterocarpus affinis Faxon, 1893 and Pandalus amplus Bate, 1886. Sex ratio (n = 46) F:M was 0.6:1. The carapace/total length relationship was significantly different between sexes, while fresh weight/total length relationship was not (t-test on slope and Y intercepts; 0.95). The largest specimens (135 mm TL) barely reach 30 g (29.9 g for the largest male; 31.6 g for the largest female) of fresh weight (30-35 large size specimens per kg of fresh product). Tail weight with carapace is slightly lower than 9 g of fresh weight for the largest specimens (average of 36.5% of total fresh weight). Tail weight without carapace is in the range of 4.5 to 5.6 g for larger specimens.
Filiaciones:
Hendrickx M.E.:
U. Académica Mazatlán, Inst. de Cie. del Mar y Limnologia, UNAM, P.O. Box 811, Mazatlán, Sinaloa 82000, Mexico
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