A Staging Table of Post‐Ovipositional Development for the South American Collared Lizard Tropidurus torquatus (Squamata: Tropiduridae)

Abstract

The mouse, chicken, African clawed frog, and zebrafish are considered ¨model organisms¨ due to their extensive embryological and genetic characterization. However, they are far from representative of known diversity, impairing phylogenetic analyses of developmental patterns. Since squamates have historically received limited attention in developmental studies, we here describe the developmental sequence for Tropidurus torquatus, and provide the first post-ovipositional developmental series for the lizard family Tropiduridae. Fifteen developmental stages are described based on morphological traits such as the eye and accessory visual structures, pharyngeal arches, fusion of facial primordia, limb development, pigmentation, and scales. Organogenesis is already in progression at oviposition (Stage 28), with embryos continuing to develop at the incubation temperature of 30°C ± 1°C, and hatching after 75 ± 5 days, at Stage 42. Comparisons with other lizards show a conserved embryonic sequence, however developmental timing differences were found in features such as the pharyngeal arches, endolymphatic sacs, pigmentation and scales. The development of the phallic and cranial lip of the cloaca anlages are compared with that of other lizards. The order of T. torquatus fore- and hindlimb formation differs from that most commonly observed in lizards. The abundance and close association of this species with urban environments, as well as the ease of capturing and managing females, makes T. torquatus an attractive source of developmental data for future experimental and ontogenetic studies. Anat Rec, 300:277-290, 2017. © 2016 Wiley Periodicals, Inc.

Embryonic development of a parthenogenetic vertebrate, the mourning gecko (Lepidodactylus lugubris)

“…Paired hemiphallic bulges of L. lugubris appear at stage 32, which is later than the gecko P. picta, the same timing as some pleurodonts, acrodonts, and gymnophthalmids, but earlier than anguimorphs, and later than other pleurodonts and lacertids. 6,50,60,85,[87][88][89][90] All three podial elements appear in the forelimbs at L. lugubris stage 32, which matches the timing of most geckos, gymnophthalmids, lacertids, some acrodonts, and anguimorphs, but is earlier than other acrodonts and pleurodonts, and later than other pleurodonts. Finally, fusion of the facial primordia occurs at stage 33 which is the same timing as other geckos, some acrodonts, and anguimorphs, but earlier than lacertids, other acrodonts, and pleurodonts, and later than gymnophthalmids.…”

“…Scale bar is in substitutions per-site primordia than pleurodonts. 85 Indeed, pupil diameter of embryonic gekkotans, including L. lugubris, is relatively larger than pleurodont and lacertid pupils. 47,86 However, L. lugubris exhibit deviations from the other three gecko-specific character states.…”

“…Gekkotan development has been characterized by the following: later appearance of the paired hemiphallic bulges when compared to other squamates (excluding gymnophthalmids 84 ), appearance of the three podial elements later than acrodonts but earlier than pleurodonts, 84 larger relative pupil diameter than pleurodonts and lacertids, 85 and earlier fusion of facial F I G U R E 9 Maximum-likelihood gene tree of paralogous BMP sequences. Each paralogous BMP gene clade is highlighted in alternating colors/shades.…”

Distinct patterns of pigment development underlie convergent hyperpigmentation between nocturnal and diurnal geckos (Squamata: Gekkota)

“…However, the early onset temporal pattern of pigment development exhibited by G. kuhli has not been described in any other gecko species to date [26,31,37,43,45,74,78,80,83], let alone other lizard species (e.g. [18,42,46,53]). Heterochrony, specifically an early onset of melanophore migration, maturation, or pigment production, may explain the hyperpigmented adult phenotype of G. kuhli (Fig.…”

The embryo of the silky shrew opossum, Caenolestes fuliginosus (Tomes, 1863): First description of the embryo of Paucituberculata

“…In this context, and due to the need of a standard method to objectively describe and compare embryonic variation and development, Werneburg (2009) proposed a Standard Event System (SES), which has been used subsequently to describe staging series (Ollonen, Da Silva, Mahlow, & Di-Poi, 2018;Polachowski & Werneburg, 2013;Roscito & Rodrigues, 2012;Werneburg, Polachowski, & Hutchinson, 2015), or as counterpart to other describing methodologies (Rapp Py-Daniel et al, 2017).…”