Morphology of the larval shell of three oyster species of the genus Crassostrea Sacco, 1897 (Bivalvia: Ostreidae).
نویسندگان
چکیده
In this study we describe the morphology of the larval shell of three oyster species of Crassostrea genus. Two species, C. rhizophorae and C. brasiliana, are native to the Brazilian coast, and C. gigas is an introduced species. Samples of laboratory reared larvae, obtained through artificial fertilisation, were collected at intervals during the cultivation process for analysis using Scanning Electron Microscopy (SEM). Prodissoconch morphology was observed in relation to the presence, position, form and number of teeth in the three larval stages: D-shaped larva, umbo larva and pediveliger. Characteristic of D-shaped larvae of C. rhizophorae was the total absence of teeth in the provinculum area while C. brasiliana and C. gigas had two anterior and two posterior teeth in each valve. In the umbo larval phase, the three species had the same number of teeth in each valve: two posterior and two anterior teeth in the right valve and three posterior and three anterior in the left valve. In the pediveliger stage the three species could be differentiated by the number of anterior teeth of the right valve: C. rhizophorae had two teeth, C. brasiliana one tooth and C. gigas three teeth.
منابع مشابه
Crassostrea gigas
Scientific names: Crassostrea gigas (Thunberg 1793), Ostreidae, Bivalvia Synonyms: Gryphaea angulata Lamarck 1819; Ostrea gigas Thunberg 1793; Ostrea laperousii Schrenk 1861; Ostrea talienwhanensis Crosse 1862. Note: The Portuguese oyster Crassostrea angulata is a name often used for this species. According to genetic studies it was shown that Crassostrea angulata is likely a strain of Crassost...
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ورودعنوان ژورنال:
- Brazilian journal of biology = Revista brasleira de biologia
دوره 70 3 شماره
صفحات -
تاریخ انتشار 2010