Biodiversidad, morfometría y alimentación de los cangrejos del género Callinectes (Decapoda: portunidae) en Santiago de Cuba / Biodiversity, morphometry and diet of Callinectescrabs (Decapoda: portunidae) in Santiago de Cuba

RESUMEN

El objetivo del presente trabajo es el estudio del género Callinectes en la zona costera del municipio de Santiago de Cuba. Se realizó una recolecta de 257 ejemplares durante marzo de 2007 a abril de 2008, en ocho estaciones a lo largo de la costa. El género resultó estar ampliamente distribuido en el litoral y representado al menos por cuatro especies C. sapidus, C. similis, C. rathbunae y C. larvatus, las dos últimas no incluidas en la lista publicada de crustáceos (Crustacea Decapoda) cubanos. Las especies más abundantes resultaron ser C. sapidus y C. similis. C. rathbunae fue la más ampliamente distribuida. El análisis del contenido estomacal permitió identificar nueve categorías alimentarias, siendo las más importantes los peces y las macroalgas. Las especies de Callinectes tienen un amplio espectro trófico; comen no sólo lo disponible, sino también lo más abundante(AU)

ABSTRACT

On the basis of fishery intensity and proximity to river mouth, a total of 257 swimming Callinectes crabs were collected from March 2007 to April 2008 in eight localities. Captures were made with hanging nets, to a maximal depth of 1.5m, establishing a top time of 2 hr. The genus was widely distributed, and it is represented at least by four species C. sapidus, C. similis, C. rathbunae and C. larvatus, the last two not included in the last list of Cuban crustaceans (Crustacea Decapoda). The size and shape of the gonopods were very useful as taxonomical criteria, considering the prevalence of males. The most abundant species were C. sapidus (47.08 percent), and C. similis (30.35 percent). C. rathbunae, which was identified at 75 percent (6) of the localities, showed a better distribution, followed by C. sapidus, which appears in the 63 percent (5). Sex rate (R s ) by species (malefemale) was 6.20 for C. rathbunae, 3.58 for C. similis, 1.40 for C. larvatus and 0.40 for C. sapidus. The most abundant species had a lower R s value. Morphometrical analysis and weight allowed us to know the average carapace width (CW) and weight (W). C. sapidus had an average CW = 110.57 mm (DS 21.55, n = 121) and W = 84.46 g (SD 43.25, n =121); C. rathbunae a CW = 115.50 mm (DS 14.94, n = 36) and W = 140.44 g (DS 55.02, n = 36); C. larvatus a CW = 76.04 mm (DS 10.88, n = 22) and W = 31.70 g (DS 14.67, n = 22); and C. similis had the minimal parameter values, with a CW = 59.77 mm (DS 14.09, n = 78) and W = 13.80g (DS 10.00, n = 78). These are the first records of the coastal crabs in the area. All values are lower than in previous reports. The largest individuals (CW>140 mm C. rathbunae and C. sapidus) were captured in localities with adequate environmental characteristics. The stomach content suggests nine dietary categories, mainly fishes and macroalgae. The genus Callinectes has a diversified trophic spectrum(AU=