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1.
Zootaxa ; 5153(1): 1-69, 2022 Jun 10.
Article in English | MEDLINE | ID: mdl-36095641

ABSTRACT

The Neotropical parrot snake genus Leptophis comprises a group of 12 colubrine snakes widely distributed in Mexico, Central- and South America. Among the currently recognized taxa in the genus, L. ahaetulla constitutes a morphologically diverse assemblage of typically slender snakes, with subspecies recorded from Mexico to most of South America. Though extremely variable in scalation, coloration, size and dentition, many of these subspecies are still poorly known, with at least three being known from few specimens, hampering the diagnosability and determination of the taxonomic status of certain populations. Accumulation of new specimens and new analytical approach for species delimitation supported a comprehensive taxonomic revision of these snakes based on the examination of meristic, morphometric, color pattern and hemipenial characters of 1625 specimens. Accordingly, the following taxa are herein referred to as full species: L. a. ahaetulla, L. a. bocourti, L. a. bolivianus, L. a. liocercus, L. a. marginatus, L. a. nigromarginatus, L. a. occidentalis, L. a. praestans and L. a. urostictus. Moreover, L. a. ortoni is placed in the synonymy of L. nigromarginatus, whereas L. coeruleodorsus, a former subspecies recently elevated to species rank, is redescribed, and L. haileyi is placed in the synonymy of this latter taxon. In addition, a dichotomous key including all recognized species of Leptophis is provided.


Subject(s)
Colubridae , Parrots , Animals
2.
Anat Rec (Hoboken) ; 303(9): 2485-2496, 2020 09.
Article in English | MEDLINE | ID: mdl-32003535

ABSTRACT

Amerotyphlops brongersmianus (Vanzolini, 1976) is distributed in Brazil from the Atlantic Rainforest to the Cerrado biome. Only few studies have focused on the gross anatomy, reproductive organs, and histological data of typhlopids. We accessed information from the anatomy of gonads of 95 individuals collected at different months in the Restinga de Jurubatiba National Park, Rio de Janeiro state, Brazil. This included histological sections of the testes, ductus deferens and sexual segment of kidney (SSK) in males, and oviducts in females, from which fecundity was determined. Results revealed a correlation between gross morphology and histology of the reproductive system. Testes volume increased during spermatogenesis, and the ductus deferens diameter increased with the presence of spermatozoa. Additionally, changes occurred in kidney morphology, which showed a smooth or rough surface, the latter corresponding to the development of the SSK. Spermatozoa were found inside the lumen of the SSK of some males. Females lacked left oviducts and showed changes in morphological and histological aspects of the right oviducts throughout the year. In summer and spring the uterus showed undeveloped structures, while during winter this organ showed conspicuously developed glands and appeared pleated and opaque upon gross examination. The infundibulum was pleated in most females throughout the year and one female had spermatozoon in a receptacle located in the posterior infundibulum. In spring, this organ was enlarged compared to winter, with a thinner epithelium. Fecundity corresponded to 7-11 eggs.


Subject(s)
Ovary/anatomy & histology , Oviducts/anatomy & histology , Reproduction/physiology , Snakes/anatomy & histology , Testis/anatomy & histology , Uterus/anatomy & histology , Animals , Brazil , Female , Male , Ovary/physiology , Oviducts/physiology , Snakes/physiology , Spermatogenesis/physiology , Spermatogonia/cytology , Testis/physiology , Uterus/physiology
3.
Zootaxa ; 4105(1): 45-64, 2016 Apr 19.
Article in English | MEDLINE | ID: mdl-27394764

ABSTRACT

The freshwater turtle Acanthochelys radiolata (Mikan, 1820) is endemic to the Atlantic Forest domain in Brazil and few studies have been done on the morphology, geographic variation and taxonomy of this species. In this paper we record the morphological variation, as well as sexual dimorphism and ontogenetic changes in A. radiolata throughout its distribution range. We analyzed 118 morphological characters from 41 specimens, both quantitative and qualitative, and performed statistical analyses to evaluate size and shape variation within our sample. Morphological analysis revealed that A. radiolata is a polymorphic species, especially regarding color and shape. Two color patterns were recognized for the carapace and three for the plastron. Diagnostic characteristics of the species, such as the rounded tubercles on the neck and the shallow dorsal sulcus between the 2nd and 4th vertebral scutes, varied considerably. Acanthochelys radiolata also showed a high level of ontogenetic variation characterized by a change on the color pattern of plastron and limbs starting from the 4th month of life. Sexual size dimorphism was observed for the first time on nine morphometric variables and females showed larger sizes than males. Based on these results we conclude that A. radiolata represents one single polymorphic species distributed in the lowlands of the Brazilian Atlantic Forest from the state of Alagoas to the state of Rio de Janeiro and the south of Minas Gerais state.


Subject(s)
Turtles/anatomy & histology , Turtles/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Body Size , Brazil , Female , Male , Organ Size , Sex Characteristics , Turtles/growth & development , Turtles/physiology , Wetlands
4.
Zootaxa ; 4012(1): 97-119, 2015 Sep 02.
Article in English | MEDLINE | ID: mdl-26623847

ABSTRACT

We conducted a taxonomic review of Chironius flavolineatus on the basis of continuous and discrete morphological characters. We recognize a new species which is distinguished from all currently recognized congeners by the following unique combination of characters: first third of body black or dark gray; vertebral stripe yellowish or creamish white distinct from dorsals of nape and extending throughout almost whole body length; head dorsum tan to brown, distinct from background color of first third of body; posterior temporal scales ranging one to four; cloacal shield frequently divided; two to four rows of keeled dorsal scales at midbody; venter ground color gradually darkening towards cloaca; region of medial constriction of hemipenis slightly covered with spinules separating calyces of apex from spines below region of constriction; in lateral view, sulcus spermaticus positioned on convex face of hemipenis; ascending process of premaxilla oblique anteroposteriorly to longitudinal axis of skull; optic fenestrae not exceeding frontoparietal suture; posterior border of supratemporal exceeding braincase; dorsoventral axis of quadrate oblique mesolaterally, moving away from longitudinal axis of skull. Furthermore, we provide data on morphological variation, distribution, and an emended diagnosis for C. flavolineatus.


Subject(s)
Colubridae/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Body Size , Colubridae/anatomy & histology , Colubridae/growth & development , Female , Male , Organ Size
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