Growing towards disparity: geometric morphometrics reveals sexual and allometric differences in Aparasphenodon brunoi (Anura: Hylidae: Lophyohylinae) head shape

Sexual dimorphism and allometry feature is the main categories of intraspecific variation found in the animal kingdom, and techniques such as Geometric Morphometrics are effective to investigate variations in shape. Considering that many vertebrates exhibit substantial allometry and sexual dimorphism, we test the hypotheses that (1) Aparasphenodon brunoi displays ontogenetic and static allometry; and that (2) there is sexual dimorphism in head shape in this species. We analyzed 75 specimens of A. brunoi from Parque Nacional da Restinga de Jurubatiba and found significant ontogenetic and static allometries in head shape, as well as sexual dimorphism after size correction. Regarding sexual dimorphism, females tend to have larger heads, besides slightly anteriorly positioned nostrils, smaller eyes, larger canthal ridges, narrower and longer frontoparietal ridges, and larger and laterally shifted squamosal ridges. We discuss the relevance of head morphology variation in the species, as well as the presumed consequences on the species fitness.Dimorfismo sexual e alometria são as principais categorias de variação intraespecífica encontradas em metazoários e técnicas como a Morfometria Geométrica são eficazes para investigar variações na forma. Considerando que muitos vertebrados exibem considerável alometria e dimorfismo sexual, testamos as seguintes hipóteses: (1) Aparasphenodon brunoi exibe alometria ontogenética e estática; e (2) existe dimorfismo sexual na forma da cabeça nesta espécie. Analisamos 75 espécimes de A. brunoi do Parque Nacional da Restinga de Jurubatiba e encontramos alometrias ontogenética e estática significativas na forma da cabeça, além de dimorfismo sexual após a correção do tamanho. Em relação ao dimorfismo sexual, as fêmeas tendem a ter cabeças maiores, além de narinas ligeiramente posicionadas mais anteriormente, olhos menores, cristas cantais maiores, cristas frontoparietais mais estreitas e mais longas e cristas esquamosais maiores e deslocadas lateralmente. Discutimos a relevância da variação da morfologia da cabeça na espécie, bem como as consequências presumidas na aptidão da mesma.Asociación Herpetológica Argentin

Growing towards disparity: geometric morphometrics reveals sexual and allometric differences in Aparasphenodon brunoi (Anura: Hylidae: Lophyohylinae) head shape

Sexual dimorphism and allometry feature is the main categories of intraspecific variation found in the animal kingdom, and techniques such as Geometric Morphometrics are effective to investigate variations in shape. Considering that many vertebrates exhibit substantial allometry and sexual dimorphism, we test the hypotheses that (1) Aparasphenodon brunoi displays ontogenetic and static allometry; and that (2) there is sexual dimorphism in head shape in this species. We analyzed 75 specimens of A. brunoi from Parque Nacional da Restinga de Jurubatiba and found significant ontogenetic and static allometries in head shape, as well as sexual dimorphism after size correction. Regarding sexual dimorphism, females tend to have larger heads, besides slightly anteriorly positioned nostrils, smaller eyes, larger canthal ridges, narrower and longer frontoparietal ridges, and larger and laterally shifted squamosal ridges. We discuss the relevance of head morphology variation in the species, as well as the presumed consequences on the species fitness.Dimorfismo sexual e alometria são as principais categorias de variação intraespecífica encontradas em metazoários e técnicas como a Morfometria Geométrica são eficazes para investigar variações na forma. Considerando que muitos vertebrados exibem considerável alometria e dimorfismo sexual, testamos as seguintes hipóteses: (1) Aparasphenodon brunoi exibe alometria ontogenética e estática; e (2) existe dimorfismo sexual na forma da cabeça nesta espécie. Analisamos 75 espécimes de A. brunoi do Parque Nacional da Restinga de Jurubatiba e encontramos alometrias ontogenética e estática significativas na forma da cabeça, além de dimorfismo sexual após a correção do tamanho. Em relação ao dimorfismo sexual, as fêmeas tendem a ter cabeças maiores, além de narinas ligeiramente posicionadas mais anteriormente, olhos menores, cristas cantais maiores, cristas frontoparietais mais estreitas e mais longas e cristas esquamosais maiores e deslocadas lateralmente. Discutimos a relevância da variação da morfologia da cabeça na espécie, bem como as consequências presumidas na aptidão da mesma.Asociación Herpetológica Argentin

Growing towards disparity: geometric morphometrics reveals sexual and allometric differences in Aparasphenodon brunoi (Anura: Hylidae: Lophyohylinae) head shape

Sexual dimorphism and allometry feature is the main categories of intraspecific variation found in the animal kingdom, and techniques such as Geometric Morphometrics are effective to investigate variations in shape. Considering that many vertebrates exhibit substantial allometry and sexual dimorphism, we test the hypotheses that (1) Aparasphenodon brunoi displays ontogenetic and static allometry; and that (2) there is sexual dimorphism in head shape in this species. We analyzed 75 specimens of A. brunoi from Parque Nacional da Restinga de Jurubatiba and found significant ontogenetic and static allometries in head shape, as well as sexual dimorphism after size correction. Regarding sexual dimorphism, females tend to have larger heads, besides slightly anteriorly positioned nostrils, smaller eyes, larger canthal ridges, narrower and longer frontoparietal ridges, and larger and laterally shifted squamosal ridges. We discuss the relevance of head morphology variation in the species, as well as the presumed consequences on the species fitness.Dimorfismo sexual e alometria são as principais categorias de variação intraespecífica encontradas em metazoários e técnicas como a Morfometria Geométrica são eficazes para investigar variações na forma. Considerando que muitos vertebrados exibem considerável alometria e dimorfismo sexual, testamos as seguintes hipóteses: (1) Aparasphenodon brunoi exibe alometria ontogenética e estática; e (2) existe dimorfismo sexual na forma da cabeça nesta espécie. Analisamos 75 espécimes de A. brunoi do Parque Nacional da Restinga de Jurubatiba e encontramos alometrias ontogenética e estática significativas na forma da cabeça, além de dimorfismo sexual após a correção do tamanho. Em relação ao dimorfismo sexual, as fêmeas tendem a ter cabeças maiores, além de narinas ligeiramente posicionadas mais anteriormente, olhos menores, cristas cantais maiores, cristas frontoparietais mais estreitas e mais longas e cristas esquamosais maiores e deslocadas lateralmente. Discutimos a relevância da variação da morfologia da cabeça na espécie, bem como as consequências presumidas na aptidão da mesma.Asociación Herpetológica Argentin

A new species of Brachycephalus (Anura: Brachycephalidae) from the northern portion of the state of Rio de Janeiro, southeastern Brazil

Abstract Brachycephalus is a genus of small ground-dwelling anurans, endemic to the Brazilian Atlantic Forest. Recent molecular analyses have corroborated the monophyly of three species groups within this genus (B. ephippium, B. ephippium, and B. ephippium). In the meantime, the genus has been targeted as a group with recent taxonomic issues owing to its interspecific morphological similarity and genetic conservatism. Herein, we describe a new species of Brachycephalus from the northern portion of Serra do Mar mountain range, in the state of Rio de Janeiro, Brazil. It belongs to the B. ephippium species group, exhibiting moderate hyperossification of the skull and vertebral column. The new species can be distinguished from all other congeners based on morphological, acoustic, and molecular data. Furthermore, we provide information on osteology and natural history of the new species

An evolutionary paradox on threadsnakes: Phenotypic and molecular evidence reveal a new and remarkably polymorphic species of Siagonodon (Serpentes: Leptotyphlopidae: Epictinae) from Amazonia

Threadsnakes are known for their conserved external morphology and historically controversial systematics, challenging taxonomic, biogeographic and evolutionary researches in these fields. Recent morphological studies—mostly based on µCT data of the skull and lower jaw—have resolved systematic issues within the group, for instance leading to the description of new taxa or re-positioning little-known scolecophidian taxa in the tree of life. Herein we describe a new polymorphic species of the genus Siagonodon from Amazonia based on morphological (external, osteology and hemipenis) and molecular data, and provide the first hemipenial description for the genus. We also reassign Siagonodon acutirostris to the genus Trilepida based on osteological data in combination with molecular evidence. The new species described represents an evolutionary paradox for scolecophidians because the species displays a remarkable variation in the shape of the snout region that is otherwise always highly conserved in this clade. Finally, this study reinforces the importance of protected areas as essential in maintaining vertebrate populations, including those that are not yet formally described

Taxonomic status and redescription of Flectonotus ulei (Anura: Hemiphractidae), with a key for the species of Fritziana

Based on preserved specimens from the states of São Paulo and Rio de Janeiro, Flectonotus ulei Miranda-Ribeiro, 1926 is resurrected from its synonymy with Flectonotus fissilis (Miranda-Ribeiro, 1920) and is redescribed. Analysis of osteological characters and brood pouch structure confirms that F. ulei belongs to Fritziana. The species is small for the genus (snout-vent length in males, 19.2-26.9 mm, n = 2; in females, 20.3-21 mm, n = 4) and was found in bromeliads. Flectonotus ulei is characterized by dorsal pattern consisting of interorbital pentagon or hexagon-shaped mark delimited by heavy dark line, diameter of tympanum smaller than that of disc of third digit, and a brood pouch covering the eggs dorsally except for a narrow longitudinal slit; eggs arranged in rosette

Taxonomic status and redescription of Flectonotus ulei (Anura: Hemiphractidae), with a key for species of Fritziana

Based on preserved specimens from the states of São Paulo and Rio de Janeiro, Flectonotus ulei Miranda-Ribeiro, 1926 is resurrected from its synonymy with Flectonotus fissilis (Miranda-Ribeiro, 1920) and is redescribed. Analysis of osteological characters and brood pouch structure confirms that F. ulei belongs to Fritziana. The species is small for the genus (snout-vent length in males, 19.2-26.9 mm, n = 2; in females, 20.3-21 mm, n = 4) and was found in bromeliads. Flectonotus ulei is characterized by dorsal pattern consisting of interorbital pentagon or hexagon-shaped mark delimited by heavy dark line, diameter of tympanum smaller than that of disc of third digit, and a brood pouch covering the eggs dorsally except for a narrow longitudinal slit; eggs arranged in rosette

A fifth species of the genus Euparkerella (Griffths, 1959), the advertisement calls of E. robusta Izecksohn, 1988 and E. tridactyla Izecksohn, 1988, and a key for the Euparkerella species (Anura: Brachycephaloidea: Craugastoridae)

Hepp, Fábio, De Carvalho-E-Silva, Sergio P., Telles De Carvalho-E-Silva, Ana M. P., Folly, Manuella (2015): A fifth species of the genus Euparkerella (Griffths, 1959), the advertisement calls of E. robusta Izecksohn, 1988 and E. tridactyla Izecksohn, 1988, and a key for the Euparkerella species (Anura: Brachycephaloidea: Craugastoridae). Zootaxa 3973 (2): 251-270, DOI: http://dx.doi.org/10.11646/zootaxa.3973.2.

Revision of the Chironius bicarinatus complex (Serpentes: Colubridae): Redefined species boundaries and description of a new species

Abstract Currently, the proposed diagnoses for the Chironius bicarinatus complex reflect a wide variation in color pattern and pholidosis. Herein, we review the Chironius bicarinatus complex based on morphological and molecular data from a sample of 485 specimens covering the species distribution. Our results corroborate the recognition of C. bicarinatus and C. gouveai, and diagnose a distinct lineage without an available name. Thus, here we describe this new species restricted to the Baturité Massif, a relictual rainforest isolated in the Caatinga xerophytic domain, in the state of Ceará, northeastern Brazil. The new species can be distinguished from its congeners by its unique combination of qualitative and quantitative morphological characters (scale counts, morphometric, color pattern), and is also supported by molecular and ecological evidence. Additionally, we rectify data on the distribution and morphological variability of C. gouveai to accurately infer the boundaries between this taxon and C. bicarinatus, which was not properly addressed. Finally, we discuss our results in the light of previous studies that suggest diversification hypotheses in the Atlantic Forest already detected for other taxa, highlighting the importance of conserving the areas of “Brejos de Altitude”, in northeastern Brazil, and the southern limit of Serra do Mar up to Serra do Tabuleiro, in southern Brazil