Biologia reprodutiva de Helicops infrataeniatus (Serpentes: Dipsadidae) da região subtropical do Brasil

Abstract

ABSTRACT 1: Reproductive biology studies are funtamental for the understanding of of the life history of a species. In this work we describe the reproductive biology of the males of Helicops infrataeniatus in a Brazilian subtropical climate environment. For this morpho-anatomical and histological analysis were realized of individuals deposited in zoological collections. The reproductive cycle was described through seasonal variation in the reproductive organs: testes, kidneys and ductus deferents. Spermatogenesis occurred during late autumn–winter (June–September), spermiogenesis occurred in spring (September–December) and complete regression of the testis were in autumn (April-May). The testis showed hypertrophy in summer (January-March), while ductus deferents presented spermatozoa all over the year and did not show seasonal variation due to sperm storage. The kidney showed increase in spring (October-December), however the tubular diameter of the sexual segment of the kidney (SSK) was increase in winter (July-Setember). Therefore, at the individual level, males exhibit a discontinuous cyclical reproduction, while population level, the reproductive cycle is seasonal semisynchronous. Finally, we discuss intrinsic and extrinsic factors that influence the reproductive strategies of H. infrataeniatus.

ABSTRACT 2: The annual activity pattern is a fundamental feature for understanding the biology of a species, and is directly associated with the individual's life stage and the reproductive biology of a species. The objective of this study is to describe the reproductive biology of the females and the seasonal activity pattern of Helicops infrataeniatus in a Brazilian subtropical climate environment. The seasonal activity of the species was described based on a study of 24-month sampling. While, the reproductive biology of females was described based on morphoanatomical and histological analyzes of individuals deposited in zoological collections. Females remain reproductively active for a long period of the year, with vitellogenic follicles in all seasons in the year and pregnant females were found in spring and summer (September-April). The peak of secondary vitellogenesis occurs in the period from June to October, ovulation in late winter and early spring (September-December) and mating during spring and summer (October-March). Then, at the individual level females exhibit a discontinuous cyclic reproductive. while population level, the reproductive cycle is seasonal semisynchronous. H. infrataeniatus presents capacity of sperm storage at the utero-vaginal junction (UVJ) and in the uteres. Maternal corporeal size is directly related to reproductive effort and fecundity.The species presents a pattern of unimodal seasonal activity, with peak activity in spring (October-December). Males and famales presente a peack of activity in spring (October-December), coinciding with the reproductive period of the species, while the juveniles showing greater activity in spring and summer (October-March), coinciding with the period of recruitment. The activity pattern of the species was influenced by variables such as air temperature and relative humidity.