Adrián Márquez

Spondylids of Eastern Pacific Ocean

ABSTRACT Members of the bivalve molluscan family Spondylidae were very important elements in the world view of pre-Hispanic cultures of America, and today remain as symbols of culture heritage in contemporary society. In recent decades, given the importance they have for crafts and jewelry, as well as for fisheries and gastronomy, their exploitation has caused a drastic decrease in natural populations leading to restrictions in fishing. In the present review, data about Spondylus species of eastern Pacific Ocean, describing the symbolism, taxonomy, distribution, biology, and ecology, their status as exploitable resources, the advances in aquaculture of these species, as well as management experiences and conservation efforts are presented.

Spat Production of the Rock Oyster Striostrea prismatica (Gray, 1825)

ABSTRACT The rock oyster Striostrea prismatica is one of the most abundant species in the rocky coastal ecosystems of the tropical and subtropical eastern Pacific; however, natural banks are overexploited or depleted, so production by culture is recommended. Adult S. prismatica obtained from natural banks were conditioned for gonad maturation and spawning. Fertilization, embryogenic, and larval development were performed under laboratory conditions, then settlement of pediveliger larvae and nursing of postlarvae were performed using downwelling methods to produce spat. The early life cycle (embryonic, larval, and postlarval development up to 5 mm in length) is described. The larval development was completed in 22 days, with survival >25%. The larval and postlarval growths were exponential reaching spat size (5 mm) after 28 days of settlement. The methods used in this study supported successful larval and postlarval culture of S. prismatica and provide a basis for large-scale propagation of this species.

Diversity and community structure of soft-bottom benthic molluscs in the Araya Peninsula, Venezuela: a baseline for the assessment of environmental impacts

The north-eastern region of Venezuela includes some of the most productive marine ecosystems of the country, sustaining high abundances of fisheries resources. This feature, coupled with the high diversity of coastal ecosystems, increases the interest for the development of conservation policies to prevent and/or mitigate negative environmental impacts associated with human interventions at the area. However, previous malacological assessments made in the Araya Peninsula are mainly restricted to epibiotic molluscs associated with bivalve banks. In this vein, we performed three different surveys for soft-bottom molluscs in the intertidal (using a stainless steel corer), shallow subtidal (Eckman dredge) and subtidal ( Arca zebra dredge) areas of Araya Peninsula. We found 41 species including Bivalvia, Gastropoda, one Cephalopoda and one Scaphopoda, although according to sample-based rarefaction techniques there may be several more undetected species. Since there is an ongoing project aiming to construct a shipping terminal on Araya Peninsula that could adversely affect coastal marine biodiversity in the region, the knowledge about the molluscan assemblage in the area is a key requirement for designing conservation measures.