Nótulas Ictiológicas: III. sôbre a ocorrência de Xenomelaniris brasiliensis (Quoy & Gaimard) no litoral do E. de S. Paulo (Brasil) (Pisces - Mugiloidei - Atherinidae)

• Autor(a) principal: Carvalho, J. de Paiva
• Data de Publicação: 1954
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Boletim do Instituto Oceanográfico
• Texto Completo: https://www.revistas.usp.br/biocean/article/view/27674

Gathering regular samples of "Peixe-rei" from the southern coast of the State of S.Paulo (Brazil), the author examined 374 specimens distributed as follows: 805 specimens caught monthly from March 20, 1952, to February 19, 1963; 39 caught in December 18, 1961, all at the same place and 30 collected at the mouth of the Santo Amaro River, in Santos. Sohultz (1949, p. 107) referring to specimens from Venezuela, in consequence of the enormous variation and small series of specimens at his disposal, had written: "...it is not possible to separate the Lago de Maracaibo population from that of the Gulf of Venezuela or of Brazil. Perhaps when an adequate number of specimens has been studied throughout the range of this species, it may be possible to break it up into subspecies. " This is the problem that the author has been trying to solve. Receiving regular samples of different age groups the author studied them carefully and concluded that he was dealing with the same species described by Quoy & Gaimard under the name of Atherina brasiliens is and, at present, included by Schultz in the genus Xenomelaniris. A comparison with 30 specimens from Santos, an harbour located in the central portion of the State coast, was made. Beginning his paper with a few considerations about the research made in relation to the South American representatives of the family Atherinidae, the author follows with an analysis of the biometrioal data obtained from the specimens collected. These data were confronted with the ones given by other authors and only slight differences in relation to number of scales and vertebrae were observed. For the time being the author believes in the existence of a mixture of genotypioal and phenotypioal characters interfering with the perfect distinction between the population of Lago de Maracaibo, Gulf of Venezuela and Brazil. Due to the difficulties of interpretation and the small differences observed in the confrontation of data, the author sees no convenience, at least for the moment, in separating the population of the State of S.Paulo into a new subspeoifioal unit. The information available concerning this species being rather poor, the author thought it useful to give the diagnosis of the specimen studied and presents a photo for illustration. A few complementary considerations are also made pointing out small osteological divergences between the material studied by the author and some diagrammatic drawings from Schultz (1948, p. 35). TheBe divergences may be attributed to the scarcity of material with which the North American author had worked. Summing up his work the author makes a reference to the presence of teeth of substitution in the maxila and mandibula of the Peixe-rei, and mentions some of the frequent anomalies found in the branchial lamelae or gill rakers of the specimen examined.