An Atlas of Reproductive Development in Rockfishes, Genus Sebastes

An Atlas of Reproductive Development in Rockfishes, Genus Sebastes

Author: Franklin R. Shaw

Publisher:

Published: 2012

Total Pages: 90

ISBN-13:

DOWNLOAD EBOOK

The genus Sebastes consists of over 100 fish species, all of which are viviparous and long-lived. Previous studies have presented schemes on the reproductive biology of a single targeted species of the genus Sebastes, but all appear to possess a similar reproductive biology as evidenced by this and other studies. This atlas stages major events during spermatogenesis, oogenesis, and embryogenesis, including atresia, in six species of Sebastes (S. alutus, S. elongatus, S. helvomaculatus, S. polyspinis, S. proriger, and S. zacentrus). Our study suggests that the male reproductive cycle of Sebastes is characterized by 11 phases of testicular development, with 10 stages of sperm development and 1 stage of spermatozoa atresia. Ovarian development was divided into 12 phases, with 10 stages of oocyte development, 1 stage of embryonic development, and 1 stage of oocyte atresia. Embryonic development up to parturition was divided into 33 stages following the research of Yamada and Kusakari (1991). Reproductive development of all six species examined followed the developmental classifications listed above which may apply to all species of Sebastes regardless of the number of broods produced annually. Multiple brooders vary in that not all ova are fertilized and progress to embryos; a proportion of ova are arrested at the pre-vitellogenic stage. Reproductive stage examples shown in this atlas use S. elongatus for spermatic development, S. proriger for oocyte development, and S. alutus for embryological development, because opportunistic sampling only permitted complete analysis of each respective developmental phase for those species. The results of this study and the proposed reproductive phases complement the recommended scheme submitted by Brown-Peterson et al. (2011), who call for a standardization of terminology for describing reproductive development of fishes.


The Rockfishes of the Northeast Pacific

The Rockfishes of the Northeast Pacific

Author: Milton S. Love

Publisher: Univ of California Press

Published: 2002

Total Pages: 472

ISBN-13: 9780520234383

DOWNLOAD EBOOK

"A major landmark contribution to fisheries science and fish ecology. Rockfish populations are in a severe decline throughout the Northeastern Pacific, and the need for a deep understanding of their biology, ecology, and management has never been more critical. This book addresses all aspects of our current knowledge of this diverse and interesting group of groundfish species, and it is written clearly and with humor. An outstanding work!"--Larry G. Allen, California State University, Northridge "Quite simply the best account ever of the fascinating, diverse, and valuable rockfishes. If you are interested in the marine fishes of the Pacific Coast, you need this book."--Peter B. Moyle, author of Inland Fishes of California


Larval Development and Identification of the Genus Triglops (Scorpaeniformes: Cottidae)

Larval Development and Identification of the Genus Triglops (Scorpaeniformes: Cottidae)

Author: Deborah M. Blood

Publisher:

Published: 2010

Total Pages: 56

ISBN-13:

DOWNLOAD EBOOK

Prior to Pietsch's (1993) revision of the genus Triglops, identification of their larvae was difficult; six species cooccur in the eastern North Pacific Ocean and Bering Sea and three co-occur in the western North Atlantic Ocean. We examined larvae from collections of the Alaska Fisheries Science Center and Atlantic Reference Centre and used updated meristic data, pigment patterns, and morphological characters to identify larvae of Triglops forficatus, T. macellus, T. murrayi, T. nybelini, T. pingeli, and T. scepticus; larvae of T. metopias, T. dorothy, T. jordani, and T. xenostethus have yet to be identified and are thus not included in this paper. Larval Triglops are characterized by a high myomere count (42-54), heavy dorsolateral pigmentation on the gut, and a pointed snout. Among species co-occurring in the eastern North Pacific Ocean, T. forficatus, T. macellus, and T. pingeli larvae are distinguished from each other by meristic counts and presence or absence of a series of postanal ventral melanophores. Triglops scepticus is differentiated from other eastern North Pacific Ocean larvae by having 0-3 postanal ventral melanophores, a large eye, and a large body depth. Among species co-occurring in the western North Atlantic Ocean, T. murrayi and T. pingeli larvae are distinguished from each other by meristic counts (vertebrae, dorsal-fin rays, and anal-fin rays once formed), number of postanal ventral melanophores, and first appearance and size of head spines. Triglops nybelini is distinguished from T. murrayi and T. pingeli by a large eye, pigment on the lateral line and dorsal midline in flexion larvae, and a greater number of dorsal-fin rays and pectoral-fin rays once formed.