Ontogeny of the skull of the blind snake Amerotyphlops brongersmianus (Serpentes: Typhlopidae) brings new insights on the snake cranial evolution

CHULIVER, MARIANA; SCANFERLA, CARLOS AGUSTÍN; KOCH, CLAUDIA

ZOOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2022

0024-4082

Blind snakes represent the mostbasal group of extant snakes and include fossorial species with unusualskeletal traits. Despite their phylogenetic position in the snake phylogenetictree, little is known about their ontogeny and what it might reveal about theorigin of their skull anatomy. Here we describe for the first time theontogenetic transformations of the skull of a blind snake, the typhlopidAmerotyphlops brongersmianus, including embryos and postnatal individuals.Furthermore, we provide data on the size changes relative to skull growth ofthe main elements of the gnathic complex. We observed that the skull of thisblind snake undergoes considerable morphological change during late ontogeny.Additionally, we detected the delayed development of some traits (closure ofthe skull roof, opisthotic-exoccipital suture, ossification of the posteriortrabeculae) simultaneously with clearly peramorphic traits (development of thecrista circumfenestralis, growth of the pterygoid bar). Our analysis suggeststhat the unique skull anatomy of blind snakes displays plesiomorphic and highlyautapomorphic features, as an outcome of heterochronic processes and miniaturization,and is shaped by functional constraints related with a highly specializedfeeding mechanism under the selective pressures of a fossorial lifestyle.@font-face{font-family:"ＭＳ 明朝";mso-font-charset:78;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1791491579 18 0 131231 0;}@font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face{font-family:Cambria;panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1073743103 0 0 415 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin:0cm;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:11.0pt;font-family:Cambria;mso-ascii-font-family:Cambria;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Cambria;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Cambria;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES-AR;mso-fareast-language:EN-US;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:Cambria;mso-ascii-font-family:Cambria;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:"ＭＳ 明朝";mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:Cambria;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-fareast-language:JA;}div.WordSection1{page:WordSection1;}