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Spawning of Basilichthys microlepidotus (Jenyns)
Author(s) -
Comte S.,
Vila I.
Publication year - 1992
Publication title -
journal of fish biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.672
H-Index - 115
eISSN - 1095-8649
pISSN - 0022-1112
DOI - 10.1111/j.1095-8649.1992.tb02724.x
Subject(s) - gonadosomatic index , biology , zoology , reproductive biology , reproduction , vitellogenesis , anatomy , fishery , oocyte , fecundity , ecology , population , embryogenesis , demography , embryo , sociology
Characteristics of the reproductive cycle of Basilichthys microlepidotus (Jenyns), an atherinid fish living in a South American Mediterranean arid zone, are analysed. Specimens 9‐170 mm in total length were captured from August 1982 to April 1984 in the Rio Choapa, in northern Chile (31%%45′ S, 71°15′ W). Analysis of gonadosomatic index fluctuations, and determination of the proportion of mature males and females captured during the study period, allowed the estimation of the duration of the reproductive cycle. Females 70–170 mm in total length contained 2000–9000 intraovarian oocytes, of which approximately 80% were vitellogenic (100–1300 μm in diameter) and exhibited a polymodal distribution. A further 4 to 15% of the total oocytes, measured 1700–2000 μm in diameter and appeared ready to be spawned. In 30% of the examined ovaries some of the largest oocytes exhibited signs of degeneration, or atresia. Juveniles approximately 30 mm in total length were captured over most of the study period. Results strongly suggest that B. microlepidotus has multiple spawnings.