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 staging tables provide information to standardize embryological investigations and to subsidize discussions about evolution. We have established a developmental staging table for Iguana iguana iguana. The sample was composed of 142 embryos, incubated at a constant temperature and collected at regular intervals. Morphological features as pharyngeal arches, craniofacial structures, eyes, limbs, claws, pigmentation, scales and egg tooth were evaluated to determine development stages. The normal staging table includes 17 stages from oviposition to hatching, based on chronology and morphological external features. Stages from 1 to 27 occur before oviposition. Stage 28 was the first described, because all embryos presented limb bud anlage, key feature of the previous stage. We used pharyngeal arches and limb buds to describe the first stages; claws, genital papilla and scales to describe the middle stages; and pigmentation, size and egg tooth to describe the last stages. Incubation lasted approximately 2 months in a controlled environment. The results were similar to the data from other lizards, confirming the embryonic conservative pattern of the group. K E Y W O R D S development, embryos, lizard, squamata | 233 LIMA et AL.

Bokermannohyla (tribe Cophomantini) is an endemic genus of Brazilian treefrogs containing 32 species arranged into four phenetic groups. The B. pseudopseudis group includes nine species, which are typically found in rupestrian ecosystems of disjunct Brazilian mountain ranges. Tadpoles have been shown to be important sources of information for the taxonomy of this genus, although careful analyses of character variation and descriptions of internal anatomy remain scarce. Since the first description of B. pseudopseudis tadpoles was based on a mixed series containing specimens of B. pseudopseudis and B. sapiranga, we describe the larvae of these two species from their type localities, including their external morphology, oral cavity, and skeletal system. Tadpoles of B. pseudopseudis are easily distinguished from those of B. sapiranga by aspects of their coloration and characters of their oral disc (more labial tooth rows, more numerous submarginal papillae and flaps with labial teeth). These morphological differences may be diagnostic for these two similar species, whereas their chondrocranium, hyobranchial apparatus, and oral cavity are alike, suggesting less variability in these character systems between closely related species. Finally, we provide the first comparison of data on the skeletal system of Bokermannohyla and other Cophomantini, highlighting characters of potential relevance to the systematics of the tribe.

Developmental studies are an important contribution to the interpretation of evolutionary patterns responsible for extant phylogenetic lineages. Squamates are a highly diverse group that is still underrepresentated in embryological investigations. The present study describes the sequence of in ovo development of Tropidurus torquatus. Gravid females were collected by noose in antropized surroundings of Brasília, Brazil, and maintained in terrariums until oviposition. Once deposition occurred, eggs were transferred to a 30ºC (± 0,1º C) temperature incubator. Daily collection of embryos were accomplished from oviposition to hatching, which took place after approximately 75 days, resulting in a total of 209 embryos obtained in two reproductive seasons. Fifteen developmental stages were established based on external morphological characteristics widely used in lizard literature such as visual structures, pharyngeal arches, facial primordial fusion, limb development, pigmentation and scales.Organogenesis was already in progression at the moment of oviposition, at which embryos resemble stage 28 of other studies. 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 order of T. torquatus fore-and hindlimb formation differs from that most commonly observed in lizards. The development of the phallic and cranial lip of the cloaca anlages are compared with that of other lizards. The adult skeleton of T.torquatus was describes and served as a guide for the developmental descriptions. The chondrocranium of T. torquatus presented reduction of orbitotemporal elements such as the teania marginalis and pila antotica. Dermal elements apparently show a conserved ossification sequence amongst lizards, main variations occurring in the ossification sequence of chondral elements. Vertebrae ossify in a cranial-caudal gradient, but are dissociated from the ossification of the ribs which do not follow this gradient. An independent center of ossification for the sacral and caudal ribs was not visualized. In the limbs, a continuous cartilaginous condensation forming a "Y" was first seen, followed by the development of the limb understructure which consists in the formation of the primary axis and the digital arch. The autopodial elements of the hindlimbs developed slightly earlier than the forelimbs. All distal carpals were seen, distal carpal I remaining in close contact with its metacarpal. The dcV did not show an embryonic connection with dcIV. In regard to the distal tarsals, only the chondrogenic condensation of distal tarsal I was not visualized. We found an embryonic connection between distal tarsal V and distal tarsal IV, indicating that dtV is probably not a de novo condensation. The distal tarsal II and V consisted in transitory condensations that rapidly fused with their respective metatarsal. Three chondrogenic elements were identified as constituents of the tarsus: fibular,...