Viviparity in the halfbeak genera Dermogenys and Nomorhamphus (Teleostei: Hemiramphidae)

Journal of Morphology
Amy Downing Meisner, John R Burns

Abstract

Gravid ovaries were examined histologically from two species of Nomorhamphus and 21 populations of Dermogenys. In addition, changes in dry-weight throughout gestation are provided for 15 populations. The ovaries are paired organs running along the lateral body wall and are separated along most of their length. In all specimens examined, embryos are fertilized within the ovarian follicle. Viviparity in these species is divided herein into five categories designated types I-V. In types I and II the entire gestation period is intrafollicular, whereas in types III-V only the early stages of gestation are intrafollicular with the major period of development occurring in the ovarian lumen (intraluminal). Type I is characterized by the retention of a large amount of yolk throughout gestation. Superfetation is not observed. Populations of D. pusilla from Vietnam and Thailand decrease in dry-weight throughout gestation. This, coupled with the slight vascularization of the yolk sac, suggests strict lecithotrophy. Populations of D. pusilla from Singapore and Bangladesh undergo an increase in dry weight and exhibit an increased vascularization of the yolk sac, suggesting a form of unspecialized matrotrophy. Type II is characterized by a sm...Continue Reading

References

Jan 1, 1991·Biotechnic & Histochemistry : Official Publication of the Biological Stain Commission·I Quintero-HunterM Muscato
Jun 1, 1978·Evolution; International Journal of Organic Evolution·Roger E Thibault, R Jack Schultz
Jul 1, 1985·Journal of Morphology·Frank M KnightJohn R Burns

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Citations

Apr 6, 2019·Journal of Morphology·María Guadalupe Guzmán-Bárcenas, Mari Carmen Uribe
Apr 17, 2010·Biological Reviews of the Cambridge Philosophical Society·Kathleen RoelligFrank Goeritz
Oct 26, 2018·Mitochondrial DNA. Part B, Resources·Kehua ZhuLiqin Liu
Mar 13, 2021·Behavioral Ecology : Official Journal of the International Society for Behavioral Ecology·Charel ReulandJohn L Fitzpatrick

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