Journal of the Marine Biological Association of the United Kingdom

Research Article

Reproductive biology of the banded guitarfish, Zapteryx exasperata, from the Gulf of California, México

María-Del-Pilar Blanco-Parraa1 c1, J. Fernando Márquez-Faríasa2a4 and Felipe Galván-Magañaa3

a1 Posgrado en Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, circuito exterior s/n, Ciudad Universitaria, México D.F. C.P. 04510, México

a2 Facultad de Ciencias del Mar, Universidad Autónoma de Sinaloa, Paseo Claussen s/n, Col. Los Pinos, Mazatlán, Sinaloa, México

a3 Centro Interdisciplinario de Ciencias Marinas, Instituto Politécnico Nacional, Avenida Politécnico Nacional s/n, Col. Playa Palo de Santa Rita, La Paz, B.C.S. México

a4 Centro Regional de Investigación Pesquera de Mazatlán, Instituto Nacional de Pesca, Calzada Sábalo–Cerritos, s/n, Mazatlán, Sinaloa, C.P. 82010, México

Abstract

The banded guitarfish, Zapteryx exasperata, is a common species in the artisanal elasmobranch fisheries in the Gulf of California. Fishery-derived specimens were examined to determine critical aspects of the reproductive biology of this poorly known group of rays. Two functional testes and ovaries were found in males and females respectively. Median size at maturity (L50%) for males was 64 cm total length (TL) and for females 69 cm TL. Average length of gravid females was 78.8±3.8 cm TL. Histological analysis showed no evidence of sperm storage in the oviducal gland. Gestation was estimated to occur over a five to six month period (February–July) and was concurrent with vitellogenesis. Mean uterine fecundity was estimated as 7 (range 2–13, SD. = 3). The sex-ratio of embryos was 1:1. The reproductive cycle for Z. exasperata from the Gulf of California was estimated to last one year with parturition, ovulation and copulation occurring during the summer months. Differences found in the reproductive cycle of Z. exasperata between the Gulf of California and the west coast of Baja California could have implications in the future management plans for this fishery in the Gulf of California.

(Received September 20 2008)

(Accepted March 17 2009)

(Online publication August 05 2009)

Correspondence:

c1 Correspondence should be addressed to: M.D.P. Blanco-Parra, Centro Interdisciplinario de Ciencias Marinas, Instituto, Politécnico Nacional, Avenida Politécnico Nacional s/n, Col. Playa Palo, de Santa Rita La Paz, B.C.S. México email: mpblancop@gmail.com