Sexual dimorphism, ontogeny and static allometry of a semi-fossorial snake (genus Atractus)

Autor(es)

Abegg, Arthur Diesel ^{[1, 2]} ; Passos, Paulo ^[3] ; Mario-da-Rosa, Conrado ^[4] ; Azevedo, Weverton dos Santos ^[1] ; Malta-Borges, Leandro ^[4] ; Bubadue, Jamile de Moura ^{[4, 5]}

Afiliação do(s) autor(es)

^[1] Inst Butantan, Lab Colecoes Zool, Ave Vital Brazil 1500, BR-05503900 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Dept Zool, Inst Biociencias, Programa Posgrad Zool, Travessa 14, Rua Matao 321, Cidade Univ, BR-05508090 Sao Paulo, SP - Brazil

^[3] Univ Fed Rio de Janeiro, Museu Nacl, Dept Vertebrados, BR-20940040 Rio De Janeiro, RJ - Brazil

^[4] Univ Fed Santa Maria, Programa Posgrad Biodiversidade Anim, Ave Roraima 1000, BR-97105900 Santa Maria, RS - Brazil

^[5] Univ Estadual Norte Fluminense, Lab Ciencias Ambientais, BR-28013602 Campos Dos Goytacazes, RJ - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ZOOLOGISCHER ANZEIGER; v. 287, p. 95-104, JUL 2020.
• Citações Web of Science: 0

Resumo

Sexual dimorphism in snakes has been mainly evaluated for size and number of some morphological traits, but few studies address on sexual shape dimorphism. Here we evaluated the existence of sexual size and shape dimorphism in the semi-fossorial snake Atractus reticulatus. We use linear and geometric morphometrics to evaluate differences between sexes and among different ontogenetic stages (neonates, juveniles and adults). We have shown that A. reticulatus is sexually dimorphic for some traits such as body length and head shape, with females being larger and having more robust heads than males, but the sexes do not differ in head size. Males and females are sexually dimorphic in head shape even in neonates, suggesting that this differentiation is prenatal. Differences in head shape may be associated with trophic segregation, allowing females to feed on larger prey than males. Body size dimorphism progressively increases throughout the ontogenetic stages, which is possibly related to the late sexual maturation of females and/or different growth rates between the sexes. We also found that males and females shows some sex-specific patterns towards static and ontogenetic allometry, with males showing stronger predictive response on static allometry than females, whereas females have ontogenetic allometry, but males do not. Additionally, the allometric slopes in A. reticulatus between sexes converge by presenting similar shapes as head size increases, an expected result for sexes with similar lifestyles. Further investigation on some physiological and natural history aspects in Atractus will be particularly useful for a better understanding of the significance of the morphological differences found in this study. (c) 2020 Elsevier GmbH. All rights reserved. (AU)

• Processo FAPESP: 19/03587-9 - Escalas da biodiversidade: estudos integrados de evolução e função de venenos ofídicos nos múltiplos níveis da diversidade
• Beneficiário: Weverton dos Santos Azevedo
• Modalidade de apoio: Bolsas no Brasil - Programa Capacitação - Treinamento Técnico