Ultrasonographic and radiographic evaluation of gestation in golden lanceheads (Bothrops insularis) in ex situ breeding programs

The golden lancehead (Bothrops insularis) is a critically endangered snake endemic to Queimada Grande Island, southeastern Brazil. Captive breeding programs are vital for the conservation of this species. This study evaluates the gestation of two females golden lanceheads using radiography and ultrasonography. The first female was collected on the island while reproductively active (late vitellogenesis or early pregnancy) and kept in captivity. This female gave birth to five neonates after an 8-month gestation period, which is longer than estimates based on specimens preserved in museums. The second female copulated in captivity in July and probably ovulated in October. In this case, no embryonic development was detected, and the female deposited 14 undeveloped eggs approximately 6 months after ovulation.

First report of male–male combat in free-ranging Amazonian Common Lanceheads (Bothrops atrox)

In many snakes, males engage in agonistic interactions (male–male combat) apparently to establish dominant–subordinate relationships to gain priority access to reproductive females. In the Neotropical genus Bothrops Wagler, 1824 (∼45 species), male–male combat has been recorded only in three species of the monophyletic Bothrops atrox group. However, most male combats recorded in this clade occurred in captivity, an environment that facilitates the emergence of agonistic interactions. Here, we provide the first record of male–male combat in free-ranging Amazonian Common Lanceheads (Bothrops atrox (Linnaeus, 1758)) and discuss the implications of this observation for the species mating system. During fieldwork, we found one immature female and five active adult males, two of them fighting. These observations suggest that reproductive male B. atrox actively search and compete for widely dispersed and scarce receptive females.

Reproductive cycles of neotropical boid snakes evaluated by ultrasound

Snakes have increasingly been bred as pets around the world. Few studies have addressed the reproduction of boid snakes, and no study has addressed their reproductive cycles in captivity. Thus, this paper describes the reproductive aspects of Brazilian boids in captivity. We used ultrasonography to characterize the reproductive cycle of four boid species in captivity in the Southern Hemisphere: the anaconda (Eunectes murinus), the red-tailed boa (Boa constrictor constrictor), the Amazon tree boa (Corallus hortulanus), and the rainbow boa (Epicrates cenchria). Nonvitellogenic follicles occurred from January to December in anaconda and red-tailed boa and for a shorter period from September to February in Amazon tree boa and from January to May in rainbow boa. Vitellogenesis occurred from late June to late March in E. murinus in year-round (12 months), from March to March in Amazon tree boa, from late September to late March in red-tailed boa, and from late March to late September in rainbow boa. Mating occurred from late March to late September in red-tailed boa and rainbow boa and from late September to late March in Amazon tree boa. No mating was observed in anacondas, but a female probably underwent parthenogenesis. Births occurred in July in anaconda and in March to July in Amazon tree boa and from December to March in red-tailed boa and rainbow boa. In males, increases in testicular size were associated with the mating season. Ultrasonography proved to be a safe and noninvasive technique to study the reproductive cycle of giant snakes in captivity.

Bites by Philodryas olfersii (Lichtenstein, 1823) and Philodryas aestiva (Duméril, Bibron and Duméril, 1854) (serpentes, dipsadidae) in São Paulo, Brazil: A retrospective observational study of 155 cases

Despite the biological relevance and abundance of non-front-fanged colubroid snakes, little is known about the medical significance of the majority these species. Herein, we described bites by two green racer species of colubroid snakes, with respect to clinical, epidemiological, and biological features. We retrospectively analyzed proven cases of Philodryas olfersii and Philodryas aestiva bites. Only cases in which the causative animal was brought and identified by an expert were included. Analysis included variables related to the snake, patient demographics, clinical findings, whole blood clotting time (WBCT20), and treatments. Total 155 medical records were analyzed, of which 141 and 14 patients each were bitten by P. olfersii and P. aestiva, respectively. Most bites occurred in spring and summer seasons, predominantly during daytime. Most snakes were female and adult. Bites by P. olfersii adults were more frequent in summer (p < 0.001) and spring (p < 0.001). The hands were most frequently bitten by P. olfersii (59.6%), while the feet and legs (71.4%) were most bitten by P. aestiva. The most common local signs or symptoms observed were pain, edema, erythema, and transitory local bleeding. Severe pain, extensive edema, ecchymosis, and paresthesia were present only in patients bitten by P. olfersii. Significant association was observed between local bleeding and adult snakes (p = 0.019), as well as between the snout-vent-length and pain (p = 0.018), extensive edema (p = 0.024), and erythema (p = 0.047). WBCT20 was normal in the 35 cases in which it was available. Two patients were wrongly treated with anti-Bothrops antivenom. These results indicated that most accidents caused by P. olfersii and P. aestiva present mild local symptomatology. Some bites of P. olfersii bites may present local symptoms, resembling bites by Bothrops-like snakes. Physicians should be informed about these kinds of accidents, to avoid unnecessary distress to the patient and over prescription of antivenom.

Short-term cold storage of seminal samples of the golden lancehead pitviper (Bothrops insularis)

Assisted reproductive technologies such as cooling, freezing, and artificial insemination are essential in conserving genetic diversity of critically endangered reptiles like the golden lancehead pitviper (Bothrops insularis). Therefore, we examined viability of semen samples from captive golden lanceheads diluted in coconut-water based extender over a 48-h period of cooling (5°C). Semen evaluations were performed immediately after the dilution and at 6, 24, and 48 h, using computer-assisted sperm analysis and stains to assess plasma membrane and acrosomal status. Our findings showed that the extender and protocol employed here were effective in preserving golden lancehead pitviper spermatozoa for a short periods of time (48 h), allowing semen samples to be transported to distant locations for immediate use without the setbacks of cryopreservation.

Reproductive cycle and sperm storage of female coral snakes, Micrurus corallinus and Micrurus frontalis

We analyzed the hypothesis that the lack of synchronization between the mating and ovulation period of Micrurus frontalis (BRT clade) is indicative of the capacity of females to store sperm. Conversely, since these reproductive events occur in the same season for Micrurus corallinus (BRM clade), sperm storage is not expected. Thus, we analyzed the reproductive cycle of female M. corallinus and M. frontalis, and investigated the occurrence of sperm storage. Our results showed that these two species of coral snakes (clades BRM and BRT) possess different reproductive cycles. Micrurus frontalis exhibits an extensive reproductive period encompassing three seasons (summer, autumn and winter), while M. corallinus directs secondary vitellogenesis and ovulation to the hottest period of the year (spring and summer). We confirm, for the first time, the strategy of sperm storage (SSr) in females of the genus Micrurus. We observed sperm storage receptacles located in the non-glandular uterus in all seasons of the year for M. corallinus and in spring, summer and autumn in M. frontalis. Furthermore, the presence of SSr in females in the non-reproductive (post-ovulatory) period, the verification of myoid cells around the receptacles and secretion of neutral carbohydrates in the lumina of SSrs may indicates a long-term storage. The posterior infundibulum is another possible region of sperm storage by the presence of tubular ciliated gland; however, reproductive studies with other species of the genus are necessary for a better understanding of the reproductive strategies of the BRT and BRM clades.

How Does Oocyte Uptake Occur? A Macroscopic Study of the Ovarian and Oviductal Modifications for Egg Capture in the Coral-Snake Micrurus corallinus

The processes of follicular development, ovulation, egg capture, and egg transport vary among vertebrates. Therefore, analysis of the reproductive tract of several lineages is needed for understanding the evolutionary changes of the reproductive system. In turtles, the ovulated eggs are released into the coelomic cavity and taken up by one of the two oviducts, a phenomenon called extrauterine migration of eggs. However, the process of egg uptake in lizards is different. The egg is ovulated directly into the infundibulum, and oocyte uptake by the contralateral oviduct rarely occurs. The same pattern has been hypothesized to occur in snakes. To test this hypothesis, we analyzed the reproductive tract of female Micrurus corallinus preserved in zoological collections. We examined the anatomical characteristics of the infundibulum and ovary and compared the reproductive output between the ovaries to verify the mechanism of egg capture and the anatomical viability of extrauterine migration of eggs. The reproductive output of the right ovary was higher than that of the left ovary, and the higher number of eggs in the right oviduct is due exclusively to the production of the ipsilateral ovary. Several anatomical features prevent extrauterine migration of eggs, including the asymmetry of the reproductive system, the arrangement of the ovarian follicles in a single row, and the formation of a wrapping around the ovary and infundibulum by the visceral pleuroperitoneum membrane (preventing against ectopic eggs). Therefore, the hypothesis of egg capture by the contralateral oviduct is anatomically infeasible in M. corallinus and possibly in other snakes. Anat Rec, 301:1936-1943, 2018. © 2018 Wiley Periodicals, Inc.

Composição, riqueza e abundância de anuros em um remanescente de Cerrado e Mata Atlântica no estado de São Paulo

Apesar da fauna de anuros no estado de São Paulo ser considerada a mais conhecida no país, ainda existem consideráveis lacunas amostrais no estado, sobretudo em remanescentes de vegetação natural das bacias hidrográficas do rio Paranapanema. Neste contexto, o objetivo deste estudo foi gerar informações sobre a composição, riqueza e abundância de anuros na Estação Ecológica de Angatuba, um remanescente de Cerrado e Mata Atlântica presente na bacia hidrográfica do Alto Paranapanema. O levantamento das espécies foi realizado em duas etapas de campo: março e novembro de 2007 e outubro de 2008 a março de 2009, totalizando 38 dias de inventário. A amostragem foi realizada por meio de armadilhas de interceptação e queda, encontro ocasional, procura auditiva e procura visual. Foram registradas 31 espécies de anuros pertencentes a 16 gêneros e oito famílias (Bufonidae, Centrolenidae, Craugastoridae, Cycloramphidae, Hylidae, Leiuperidae, Leptodactylidae e Microhylidae). Deste total, 15 espécies representam novos registros para os municípios de Angatuba e Guareí, SP. Este estudo é uma importante contribuição para ampliar o conhecimento sobre a diversidade de anuros no Cerrado e Mata Atlântica, os dois hotspots mundiais prioritários para a conservação biológica existentes no país.

Herpetofauna de um remanescente de cerrado no estado de São Paulo, sudeste do Brasil

Apesar da grande extensão e biodiversidade, ainda existem lacunas amostrais no Cerrado. Este domínio fitogeográfico vem sofrendo modificações acentuadas devido à sua conversão em pastagens e monoculturas. Nas últimas quatro décadas ocorreu uma redução de 88,5% das áreas de Cerrado no estado de São Paulo. Restam menos de 0,8% da área original do Cerrado paulista, que originalmente cobria 14% da área do estado. Este estudo apresenta a composição de espécies, abundância e uso de hábitat dos anfíbios e répteis que ocorrem na Estação Ecológica de Assis, um remanescente de Cerrado no estado de São Paulo. O inventário foi realizado entre setembro de 2007 e março de 2008, em sete etapas de campo mensais de cinco dias cada, totalizando 35 dias de trabalho de campo. A amostragem foi realizada por meio de armadilhas de interceptação e queda (AIQ), encontros ocasionais (EO), procura auditiva (PA) e procura visual (PV). Além da amostragem em campo, foram incluídos na lista de espécies os registros obtidos para o município de Assis presentes nas principais coleções científicas de anfíbios e répteis do estado de São Paulo. Foram registradas 27 espécies de anfíbios pertencentes a 13 gêneros e seis famílias (Bufonidae, Cycloramphidae, Hylidae, Leiuperidae, Leptodactylidae e Microhylidae) e 53 espécies de répteis pertencentes a 38 gêneros e 13 famílias (Amphisbaenidae, Anguidae, Gekkonidae, Gymnophthalmidae, Polychrotidae, Scincidae, Teiidae, Anomalepididae, Boidae, Colubridae, Dipsadidae, Elapidae e Viperidae). Este estudo é uma importante contribuição para o conhecimento destas taxocenoses no ameaçado Cerrado paulista. Nesse sentido, remanescentes como a Estação Ecológica de Assis são de extrema importância não só para a conservação da herpetofauna no estado de São Paulo, mas também para o domínio do Cerrado.