The Kenyan caecilian, Boulengerula taitanus inhabits a climate characterised by two distinct dry and wet seasons, and a single thermal minimum in June. It is oviparous with direct development and a remarkable dermatophagous maternal care, but the female reproductive cycle until now remains unknown. The purpose of this work was to complete the knowledge about the reproductive modes of this species, using anatomical and histological studies of the ovaries. Quantitative variations of follicle categories showed a continuous folliculogenesis. Yet, young corpora lutea were only detected between November and February during the short rain season and the short dry season, indicating ovulation occurred during these four months during the thermal maximum. Oestrogen and progesterone detection allowed determination of three reproductive periods during the year: preparation in September and October, ovulation from November until February and quiescence from March until August. So, the female reproductive cycle of B. taitanus appears to be annual and synchronised with testicular evolution. Because the ovulation was observed following the second peak of follicle production (beginning of June), temperature is supposed to be the main regulating factor of reproductive pattern in this caecilian.

Typhlonectes compressicauda is an aquatic gymnophionan amphibian living in South America. Its breeding cycle is linked to seasons, characterized by a regular alternation of rainy and dry seasons. During a complex biennial cycle, the female genital tract undergoes a series of alternations of increasing and decreasing, governed by equilibrium of proliferation and apoptotic phenomena. Immunohistochemical methods were used to visualize cell proliferation with the detection of Ki67 antibody, a protein present in proliferative cells; terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and Apostain were performed to detect apoptotic cells on sections of ovaries and oviducts. In ovaries, both phenomena affect the germinal nests and follicles according to the cycle period. In the oviduct, the balance was in favor of proliferation during preparation for reproduction, and in favor of apoptosis when genital ducts regress. Apoptosis and proliferation are narrowly implicated in the remodeling of the genital tract and they are accompanied by the differentiation of tissues according to the phase of the breeding cycle. These variations permit the capture of oocytes at ovulation, always at the same period, and the parturition after 6–7 months of gestation, at a period in which the newborns live with their mother, protected in burrows in the mud. During the intervening year of sexual inactivity, the female reconstitutes body reserves.

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