Diurnal spermatogenesis and spawning in the secondary male of a protogynous wrasse, Pseudolabrus japonicus (Teleostei, Labridae)

Michiya Matsuyama, Sumito Morita, Nobuhide Hamaji, Masaaki Kashiwagi, Kohei Ohta, Yoshitaka Nagahama

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The bambooleaf wrasse, Pseudolabrus japonicus, exhibits diandric protogyny, and the secondary male performs pair spawning with a female who enters his territory. We examined diurnal spermatogenesis and spawning in the secondary male of a protogynous wrasse. In captivity, a single secondary male spawned daily over one month between 06:00 and 09:00 from October to November. Number of B-type spermatogonia and spermatocytes showed the lowest level at 00:00, increased gradually thereafter, peaked at 15:00, and decreased rapidly from 21:00 to 00:00. Spermatid number did not change significantly throughout the day. The number of spermatozoa increased gradually from 18:00, reached a maximum at 06:00, just prior to spawning, and thereafter decreased markedly at 09:00, after spawning. These results clearly showed that spermatogonial proliferation and meiosis occurred between 00:00 and 15:00, and spermiation occurred between 18:00 and 06:00. Thus, the secondary male of bambooleaf wrasse exhibits a diurnal rhythm of spermatogenesis and spermiation.

Original languageEnglish
Pages (from-to)1001-1008
Number of pages8
JournalZoological Science
Volume14
Issue number6
DOIs
Publication statusPublished - 1997

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Labridae
spermatogenesis
spawning
spermiation
protogyny
spermatogonia
spermatocytes
spermatids
meiosis
circadian rhythm
spermatozoa
Pseudolabrus

All Science Journal Classification (ASJC) codes

  • Animal Science and Zoology

Cite this

Diurnal spermatogenesis and spawning in the secondary male of a protogynous wrasse, Pseudolabrus japonicus (Teleostei, Labridae). / Matsuyama, Michiya; Morita, Sumito; Hamaji, Nobuhide; Kashiwagi, Masaaki; Ohta, Kohei; Nagahama, Yoshitaka.

In: Zoological Science, Vol. 14, No. 6, 1997, p. 1001-1008.

Research output: Contribution to journalArticle

Matsuyama, Michiya ; Morita, Sumito ; Hamaji, Nobuhide ; Kashiwagi, Masaaki ; Ohta, Kohei ; Nagahama, Yoshitaka. / Diurnal spermatogenesis and spawning in the secondary male of a protogynous wrasse, Pseudolabrus japonicus (Teleostei, Labridae). In: Zoological Science. 1997 ; Vol. 14, No. 6. pp. 1001-1008.
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