SistemÃtica e morfometria multivariada de Pyramidellidae (Gastropoda, Heterobranchia)

AUTOR(ES)
DATA DE PUBLICAÇÃO

2003

RESUMO

The mollusks of the family Pyramidellidae Gray, 1840 (Gastropoda, Heterobranchia, Heterostropha)are composed by marine gastropods usually foud in intertidal sediments or dragged in vary deepth, during the oceanographics expedition, and are represented by very small shells, some are minute in length. The principal conchiological diagnostic of this family is the presence of a sinistral heterostrophic apex, with a dextral teleoconch. The position of the apex on the teleoconch axis, varied the 90 to 180Â. The material utilized in this study had following origins: 1. Manual samples collected along coastal beach rocks and shifting sediments of the intertidal zone existing along the coast of Pernambuco; 2. Sediments dragged during the âCanopusâ oceanographic expedition, realized on the continental shelf, taken place off the coasts between Cearà to Sergipe States; 3. Sediments dragged in deep sea during the oceanographic ship Almirante CÃmara off the marginal Plateau of Pernambuco. 4. Sediments dragged by the fishing boat âNaturezaâ (CEPENE/IBAMA), during the REVIZEE â ProspecÃÃo program, between Pernambuco and Sergipe States. The conchiological material was selected under a stereomicroscope, and shells were posteriorly studied using a scanning electron microscope (SEM). The study of the multivariate morphometry measures and the phylogeny were realized with the helping of the analysis of 21 linear measures, five angular measures, including the morphometric relations, conchiological indicator, meristic and descritive date, which were analysed by the multivariate and descritive statistical methods. The analysis of the morphological dispersion, contributed to test the systematic supposition of the conchiological affinity the correlationed taxa. The systematics studies has made possible the identification of 22 genera and 51 species of the Pyramidellidae. The existence of 28 species and eight genera compose the first recording of their presence to the Brazilian coast. A parcimonious phylogenet analysis cannot be entirely presented to the all taxa studied, thus, a great number of the studied characters explained the high conchiological relation existent among the taxa. The observation on the groups, resulted on the formation of the phylogents standards, mono and polifiletics, thus, are recomended the use of the multivariate analysis to the identification and grouping of the morphology of the subfamilies Pyramidellinae and Odostomiinae

ASSUNTO(S)

pyramidellidae malacofauna oceanografia pernambuco microgastrÃpodes

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