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Miguel Trefaut Rodrigues - One of the best experts on this subject based on the ideXlab platform.
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Two New Highland Species of Amphisbaena Linnaeus, 1758 (Amphisbaenia, Amphisbaenidae) from Bahia State, Brazil
South American Journal of Herpetology, 2019Co-Authors: Mauro Teixeira Junior, Francisco Dal Vechio, Renato Recoder, José Cassimiro, Marco Aurélio De Sena, Miguel Trefaut RodriguesAbstract:Two new species of Amphisbaena are described from Bahia, one from Piata municipality with two precloacal pores, 232 body annuli, 27 caudal annuli, autotomic site at the 7th caudal annulus, and 16 dorsal and 18 ventral segments per annuli at midbody, and the other from Vitoria da Conquista with four precloacal pores, 208 body annuli, 25 caudal annuli, autotomic site at the 10th caudal annulus, and 14 dorsal and 16 ventral segments. The species from Vitoria da Conquista municipality is morphologically more similar to A. mensae than the new species from Piata. Despite their morphological differences, phylogenetic analysis of molecular data revealed that the new species are closely related, with the previously described species recovered in distinct clades.
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Diagnostic clarification, new morphological data and phylogenetic placement of Amphisbaena arenaria Vanzolini, 1991 (Amphisbaenia, Amphisbaenidae).
Zootaxa, 2016Co-Authors: Mauro Junior Teixeira, Francisco Dal Vechio, Miguel Trefaut RodriguesAbstract:Several decades ago, Vanzolini (1991) described Amphisbaena arenaria Vanzolini, 1991 based on a single individual (MZUSP 65817) collected at Raso da Catarina, a large flat sandy deposit at the southern bank of Sao Francisco River. In the same paper he described A. frontalis Vanzolini, 1991 based on specimens collected at another sandy area, at the northern bank of Sao Francisco River, both in Bahia state, Brazil. As conflicting values are presented throughout his paper, the diagnosis of A. arenaria still needs clarification. We here comment on these differences and re-diagnose A. arenaria including new topotypic material, providing its phylogenetic placement and a new state record.
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A New Two-Pored Amphisbaena Linnaeus, 1758, from Western Amazonia, Brazil (Amphisbaenia: Reptilia)
South American Journal of Herpetology, 2014Co-Authors: Mauro Teixeira, Francisco Dal Vechio, Antonio Mollo Neto, Miguel Trefaut RodriguesAbstract:Abstract. Recent efforts to improve sampling of Brazilian biodiversity have yielded a number of undescribed species of amphisbaenids. Herein, we describe a new species of small, two-pored Amphisbaena from western Brazilian Amazonia. The new species can be distinguished from all congeners by the combination of the following characters: two precloacal pores arranged in a continuous series; snout rounded in lateral and dorsal views; tip of tail rounded; 233–250 body annuli; 20–24 caudal annuli; autotomy sites on caudal annuli 6–9; 10 dorsal and 12–14 ventral segments per annulus at midbody; absence of postmalars; suture between frontals slightly smaller than parietal and nasal sutures; and tail short relative to body length (tail length/body length = 0.10). The new species inhabits the rain forest and small patches of savanna vegetation within the Amazon Forest. A Bayesian analysis based on two mitochondrial (16S and ND2) and three nuclear (cmos, BNDF and RAG1) markers recovered the new species as sister to ...
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A new Amphisbaena with chevron-shaped anterior body annuli from state of Pernambuco: Brazil (Squamata: Amphisbaenidae)
Zootaxa, 2009Co-Authors: Tamí Mott, Miguel Trefaut Rodrigues, Ednilza Maranhão Dos SantosAbstract:A new species of Amphisbaena is described from Fazenda Porto Seguro, municipality of Buique, state of Pernambuco, in the Caatingas of northeastern Brazil based on four specimens. The new species is a small and slender Amphisbaenian with four precloacal pores, 333–337 body annuli, 22–23 tail annuli with discrete evidence of an autotomic site on the 10–12 tail annuli, and 14 dorsal and 17–18 ventral segments per annuli at midbody. The high number of body annuli, the presence of chevron-shaped anterior body annuli, and the fusion of frontal scales distinguish Amphisbaena supernumeraria sp. nov. from its congeners.
Jack L Conrad - One of the best experts on this subject based on the ideXlab platform.
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phylogeny and systematics of squamata reptilia based on morphology
Bulletin of the American Museum of Natural History, 2008Co-Authors: Jack L ConradAbstract:Abstract Squamata (Amphisbaenians, “lizards”, mosasaurs, and snakes) is an extremely diverse clade with a rich fossil record. There is little consensus about the interrelationships of the major squamate clades (i.e., Iguania, Gekkota, Scincomorpha, Anguimorpha, Amphisbaenia, and Serpentes), or even the membership of some of these clades. Morphology-based cladistic analyses typically agree only that the major dichotomy in extant squamates is between Iguania and all other taxa. The phylogenetic placement of Amphisbaenia and Serpentes is particularly problematic. Incomplete taxon sampling is likely a major contributing factor to the absence of a consensus about squamate interrelationships. This study examines squamate relationships using 222 ingroup taxa scored for 363 morphological characters. Analysis of these data recovered 2,213 equally short trees with a length of 3,273 steps and a retention index of 0.7164. The results confirm the monophyly of the clades Scleroglossa (extant squamates exclusive of Igua...
Carlos Jared - One of the best experts on this subject based on the ideXlab platform.
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Rudimentary Eyes of Squamate Fossorial Reptiles (Amphisbaenia and Serpentes)
Anatomical record (Hoboken N.J. : 2007), 2009Co-Authors: Giselle Foureaux, Carlos Jared, Marta M. Antoniazzi, Mizue Imoto Egami, Robson Campos Gutierre, Ricardo Luiz SmithAbstract:The rudimentary characteristic of the eyes of fossorial animals raises some questions regarding its evolution and functionality. Would these eyes result from atrophy or from stagnated development? How would its visual function work? Anatomical investigations of these organs are the fundamental preamble to answer those questions, which are still little explored by the literature. In this article we have studied anatomical aspects of the eyes of three species of fossorial reptiles, within the suborder Amphisbaena (Amphisbaena alba, Amphisbaena mertensi, Leposternon infraorbitale), as well as a species within the ophidian suborder (Typhlops brongersmianus). The minuscule eyes (1–2 mm diameter) were visualized through a scale, a translucent area which corresponds to the spectacle. This spectacle is a thinner and transparent scale, covering a conjunctival sac. The retrobulbar space was filled with the harderian gland. The eyes of Typhlops presented an oval shape, whereas Amphisbaena specimens presented cup-shaped eyes. In Amphisbaenian sclera is comprised of cartilage, while the thin sclera of Typhlops consists of connective tissue and striated muscle fibers. The retina presented all the typical layers found in vertebrates, regardless the species. The characteristics involved in the fossil adaptation of these species include: reduced size of the eyeball, rudimentary cornea, absence of the anterior chamber, presence of a complex iris-ciliary body, and lens with amorphous nucleate cells. The analysis of the eye morphology of these animals suggests that there might be a specific function concerning light perception. Anat Rec, 2010. © 2009 Wiley-Liss, Inc.
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Morphological and physiological specialization for digging in Amphisbaenians, an ancient lineage of fossorial vertebrates
Journal of Experimental Biology, 2004Co-Authors: Carlos A. Navas, Carlos Jared, Marta M. Antoniazzi, José Eduardo De Carvalho, José Guilherme Chaui-berlink, Rob S. James, Tiana Kohlsdorf, Maeli Dal Pai-silva, Robbie S. WilsonAbstract:Amphisbaenians are legless reptiles that differ significantly from other vertebrate lineages. Most species dig underground galleries of similar diameter to that of the animal. We studied the muscle physiology and morphological attributes of digging effort in the Brazilian amphisbaenid Leposternon microcephalum (Squamata; Amphisbaenia), which burrows by compressing soil against the upper wall of the tunnel by means of upward strokes of the head. The individuals tested (
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Epidermal glands in Squamata: microscopical examination of precloacal glands in Amphisbaena alba (Amphisbaenia, Amphisbaenidae).
Journal of morphology, 1999Co-Authors: Carlos Jared, Marta M. Antoniazzi, Jose Roberto Machado Cunha Da Silva, Edna FreymüllerAbstract:The femoral or cloacal region of many species of lizards and Amphisbaenians exhibits epidermal glands. The pores of these glands are plugged with holocrine solid secretions that serve as semiochemical sources. Many authors assume that these glands are mainly associated with reproduction and demarcation of territory. The structure of precloacal glands in Amphisbaena alba was previously studied by Antoniazzi et al. (Zoomorphology 113:199-203, 1993; J. Morphol. 221:101-109, 1994). These authors suggested that as the animal moves inside tunnels, the secretion plugs are abraded against the substrate, releasing a secretion trail. Some aspects of the plug were difficult to interpret in fine sections due to the dense and brittle nature of the plug. The morphology of the trail, and the manner of deposition on the substrate, have never been reported. This study presents a primarily scanning electron microscopic description of A. alba precloacal glands and of the secretion plugs. It also demonstrates experimentally the formation of the trail and its fine morphology. The results show that when the plugs scrape against the substrate, their constitution helps them to fragment into tiny pieces, which are spread on the ground, thus forming a trail. Each one of the fragments corresponds to a secretion granule of the precloacal gland's secretory cells. In this way, the trail might have an extensive area for volatilization of semiochemicals, constituting an efficient means of intraspecific communication inside the tunnels.
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a possible advantage of displaying the tail a comparison between the tail and body integument structure in amphisbaena alba and leposternon microcephalum squamata Amphisbaenia
Annales Des Sciences Naturelles-zoologie Et Biologie Animale, 1998Co-Authors: Carlos Jared, Marta M. Antoniazzi, Edna Freymüller, Luiz Carlos Uchoa JunqueriraAbstract:Abstract Amphisbaena alba when in a defensive position adopts a horseshoe posture, raises its head and tail and opens its mouth. The tail is rigid; the dorsal surface often has non-pigmented areas which resemble scars. Leposternon microcephalum lives sympatrically with A. alba; it has a soft tail which does not appear to be involved in defensive display. Both species have been observed in captivity. The height to which A. alba raises head and tail during defensive display was measured. Morphometrics and morphology of the integument structure in both species were studied in the body and in the tail from the collagen bundles organization viewpoint. The results reveal a mechanical resistance of the tail in A. alba, but not in L. microcephalum. It is possible that this structure, formed of a dense piece of collagen, serves as a ‘biting block’ ; lesions caused by potential predators could cause no great harm. The skin of the remainder of the body in A. alba (but not in L. microcephalum) is also very resistant; the animal is practically covered by a flexible armour.
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Comparative cytomorphology of maturing Amphisbaenian (Amphisbaena alba) and snake (Waglerophis merremii) erythroid cells with regard to haemoglobin biosynthesis
Comparative Haematology International, 1998Co-Authors: D. D. Spadacci-morena, O. Brunner, P. Morena, Carlos Jared, Marta M. Antoniazzi, A. BrunnerAbstract:A comparativeultrastructural study on organelles involved in haemoglobin (Hb), biosynthesis processing in the course of Amphisbaena alba (Amphisbaenia, Squamata, Reptilia) and Waglerophis merremii (Ophidia, Squamata, Reptilia) erythroid cells maturation, was accomplished; for this purpose, erythropoiesis was enhanced by phenylhydrazine hydrochloride and saponin, respectively. The fossorial Amphisbaenians, which live in an hypoxic environment, denoted a lower metabolic rate than that of snakes; they presented a slow response to intoxication and to anaesthesia, and an apparently slow transformation of erythroid cell organelles for Hb biosynthesis. Iron uptake, probably via transferrin, results in accumulation in the form of siderosomes, which constitute iron sources for haeme biosynthesis. The inner compartment membrane of mitochondria differentiates to a lamellated body, from which a long doubly lamellated expansion arises for ferruginous compounds and globin polypeptides gathering; by folding upon itself the expansion compartmentalises all caught material into a prehaemosomal vesicle, which condenses and changes to a prohaemosome. This stage is followed by a haemosome, wherein haeme and globin assembly and the final Hb molecule formation take place. Basically, haemosomegenesis is very similar in the two squamates, as in other vertebrates, except that Amphisbaenian erythroid cells exhibit haemosomes containing Hb molecules temporarily arranged in a transverse disposition, like steps within the organelle matrix.
Theodore J. Papenfuss - One of the best experts on this subject based on the ideXlab platform.
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The complete mitochondrial genome of an agamid lizard from the Afro-Asian subfamily agaminae and the phylogenetic position of Bufoniceps and Xenagama.
Molecular phylogenetics and evolution, 2006Co-Authors: J. Robert Macey, James A. Schulte, Jonathan J. Fong, Indraneil Das, Theodore J. PapenfussAbstract:Squamate reptiles are traditionally divided into six groups: Iguania, Anguimorpha, Scincomorpha, Gekkota (these four are lizards), Serpentes (snakes), and Amphisbaenia (the so-called worm lizards). The Iguania is recognized as having two major lineages the Iguanidae and Acrodonta (Agamidae and Chamaeleonidae). Currently, there are complete mitochondrial genomes from three Anguimorpha (Kumazawa, 2004; Kumazawa and Endo, 2004), two from the Scincomorpha (Kumazawa, 2004; Kumazawa and Nishida, 1999), one from Gekkota (Macey et al., 2005) two from Serpentes (Kumazawa, 2004; Kumazawa et al., 1998) and 12 from Amphisbaenia (Macey et al., 2004). In addition, two representatives of the Iguanian family Iguanidae (Janke et al., 2001; Kumazawa, 2004) have been sequenced. Its’ sister taxon, the Acrodonta, consists of seven monophyletic groups-the family Chamaeleonidae and six distantly related subfamilies of the family Agamidae (Macey et al., 2000b). Currently, the only acrodont lineage sequenced for the complete mitochondrial genome is Pogona vitticeps from the Australasian agamid subfamily Amphibolurinae (Amer and Kumazawa, 2005a). Here, we report the complete mitochondrial genome of Xenagama taylori, a North African representative of the agamid subfamily Agaminae and compare it to P. vitticepes. The agamid lizard genus Xenagama is distributed in a
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Phylogenetic relationships among Amphisbaenian reptiles based on complete mitochondrial genomic sequences
Lawrence Berkeley National Laboratory, 2004Co-Authors: J. Robert Macey, Theodore J. Papenfuss, Jennifer V. Kuehl, H. Matthew Fourcade, Jeffrey L. BooreAbstract:Complete mitochondrial genomic sequences are reported from 12 members in the four families of the reptile group Amphisbaenia. Analysis of 11,946 aligned nucleotide positions (5,797 informative) produces a robust phylogenetic hypothesis. The family Rhineuridae is basal and Bipedidae is the sister taxon to the Amphisbaenidae plus Trogonophidae. Amphisbaenian reptiles are surprisingly old, predating the breakup of Pangaea 200 million years before present, because successive basal taxa (Rhineuridae and Bipedidae) are situated in tectonic regions of Laurasia and nested taxa (Amphisbaenidae and Trogonophidae) are found in Gondwanan regions. Thorough sampling within the Bipedidae shows that it is not tectonic movement of Baja California away from the Mexican mainland that is primary in isolating Bipes species, but rather that primary vicariance occurred between northern and southern groups. Amphisbaenian families show parallel reduction in number of limbs and Bipes species exhibit parallel reduction in number of digits. A measure is developed for comparing the phylogenetic information content of various genes. A synapomorphic trait defining the Bipedidae is a shift from the typical vertebrate mitochondrial gene arrangement to the derived state of trnE and nad6. In addition, a tandem duplication of trnT and trnP is observed in B. biporus with a pattern of pseudogene formation that varies among populations. The first case of convergent rearrangement of the mitochondrial genome among animals demonstrated by complete genomic sequences is reported. Relative to most vertebrates, the Rhineuridae has the block nad6, trnE switched in order with cob, trnT, trnP, as they are in birds.
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Phylogenetic relationships among Amphisbaenian reptiles based on complete mitochondrial genomic sequences
Molecular phylogenetics and evolution, 2004Co-Authors: J. Robert Macey, Theodore J. Papenfuss, Jennifer V. Kuehl, H. Matthew Fourcade, Jeffrey L. BooreAbstract:Complete mitochondrial genomic sequences are reported from 12 members in the four families of the reptile group Amphisbaenia. Analysis of 11,946 aligned nucleotide positions (5797 informative) produces a robust phylogenetic hypothesis. The family Rhineuridae is basal and Bipedidae is the sister taxon to the Amphisbaenidae plus Trogonophidae. Amphisbaenian reptiles are surprisingly old, predating the breakup of Pangaea 200 million years before present, because successive basal taxa (Rhineuridae and Bipedidae) are situated in tectonic regions of Laurasia and nested taxa (Amphisbaenidae and Trogonophidae) are found in Gondwanan regions. Thorough sampling within the Bipedidae shows that it is not tectonic movement of Baja California away from the Mexican mainland that is primary in isolating Bipes species, but rather that primary vicariance occurred between northern and southern groups. Amphisbaenian families show parallel reduction in number of limbs and Bipes species exhibit parallel reduction in number of digits. A measure is developed for comparing the phylogenetic information content of various genes. A synapomorphic trait defining the Bipedidae is a shift from the typical vertebrate mitochondrial gene arrangement to the derived state of trnE and nad6. In addition, a tandem duplication of trnT and trnP is observed in Bipes biporus with a pattern of pseudogene formation that varies among populations. The first case of convergent rearrangement of the mitochondrial genome among animals demonstrated by complete genomic sequences is reported. Relative to most vertebrates, the Rhineuridae has the block nad6, trnE switched in order with the block cob, trnT, trnP, as they are in birds.
Francisco Dal Vechio - One of the best experts on this subject based on the ideXlab platform.
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Two New Highland Species of Amphisbaena Linnaeus, 1758 (Amphisbaenia, Amphisbaenidae) from Bahia State, Brazil
South American Journal of Herpetology, 2019Co-Authors: Mauro Teixeira Junior, Francisco Dal Vechio, Renato Recoder, José Cassimiro, Marco Aurélio De Sena, Miguel Trefaut RodriguesAbstract:Two new species of Amphisbaena are described from Bahia, one from Piata municipality with two precloacal pores, 232 body annuli, 27 caudal annuli, autotomic site at the 7th caudal annulus, and 16 dorsal and 18 ventral segments per annuli at midbody, and the other from Vitoria da Conquista with four precloacal pores, 208 body annuli, 25 caudal annuli, autotomic site at the 10th caudal annulus, and 14 dorsal and 16 ventral segments. The species from Vitoria da Conquista municipality is morphologically more similar to A. mensae than the new species from Piata. Despite their morphological differences, phylogenetic analysis of molecular data revealed that the new species are closely related, with the previously described species recovered in distinct clades.
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A new four-pored Amphisbaena Linnaeus, 1758 (Amphisbaenia, Amphisbaenidae) from Brazilian Amazon.
Zootaxa, 2018Co-Authors: Elaine C.s. Oliveira, Roberta Graboski, Wilian Vaz-silva, Alfredo P. Santos-jr, Mauro Teixeira, Francisco Dal Vechio, Síria RibeiroAbstract:A new species of Amphisbaena is described from the Brazilian Amazon, within the area impacted by the Teles Pires hydroelectric power plant, Jacareacanga municipality, State of Para. Amphisbaena hoogmoedi sp. nov. can be diagnosed from its congeners by the following combination of characters: snout convex in profile view, sligthly compressed not keeled; pectoral scales arranged in regular annuli; conspicuous autotomic site between 7 th –8 th caudal annuli; 247–252 dorsal half-annuli; 27 caudal annuli; tail length 9.5–10.4% of snoutvent length; four precloacal pores arranged in sequence; three supralabials; a rounded tail; 22–24 dorsal segments in midbody annulus; postmalar row absent; head length 2.1–2.9% of snout-vent length; prefrontals length 46.6–49.5% of head length; prefrontals suture length 38–44.6% of head length; small malar length 10.6–13.4% of ventral length of head ; second infralabial length 33.8–38.5% of head length; ventral length of head 2.7–2.9% of snout-vent length; mouth length 80.2–81.8% of head length; third infralabial length 16.4–19.6% of head length; snout length 62.5–78.6% of head length; ocular length 23.4–26.2% of head length; mental length 23.2–25.4% of ventral length of head; postmental length 27.2–31.3% of ventral length of head; frontals suture length 23.4–32.3% of head length; postocular width 25–31.9% of maximun width of head; first supralabial length 24.9–30.6% of head length; second supralabial length 27.7–30% of head length and second supralabial height 26.9–28.8% of maximun head height. The hemipenis is bilobed, capitate and with lateral lamellae on the lobes; with a centrally-positioned spermatic groove, bifurcated at the base of the lobes, and with each branch extending to the tip of organ.
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Diagnostic clarification, new morphological data and phylogenetic placement of Amphisbaena arenaria Vanzolini, 1991 (Amphisbaenia, Amphisbaenidae).
Zootaxa, 2016Co-Authors: Mauro Junior Teixeira, Francisco Dal Vechio, Miguel Trefaut RodriguesAbstract:Several decades ago, Vanzolini (1991) described Amphisbaena arenaria Vanzolini, 1991 based on a single individual (MZUSP 65817) collected at Raso da Catarina, a large flat sandy deposit at the southern bank of Sao Francisco River. In the same paper he described A. frontalis Vanzolini, 1991 based on specimens collected at another sandy area, at the northern bank of Sao Francisco River, both in Bahia state, Brazil. As conflicting values are presented throughout his paper, the diagnosis of A. arenaria still needs clarification. We here comment on these differences and re-diagnose A. arenaria including new topotypic material, providing its phylogenetic placement and a new state record.
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A New Two-Pored Amphisbaena Linnaeus, 1758, from Western Amazonia, Brazil (Amphisbaenia: Reptilia)
South American Journal of Herpetology, 2014Co-Authors: Mauro Teixeira, Francisco Dal Vechio, Antonio Mollo Neto, Miguel Trefaut RodriguesAbstract:Abstract. Recent efforts to improve sampling of Brazilian biodiversity have yielded a number of undescribed species of amphisbaenids. Herein, we describe a new species of small, two-pored Amphisbaena from western Brazilian Amazonia. The new species can be distinguished from all congeners by the combination of the following characters: two precloacal pores arranged in a continuous series; snout rounded in lateral and dorsal views; tip of tail rounded; 233–250 body annuli; 20–24 caudal annuli; autotomy sites on caudal annuli 6–9; 10 dorsal and 12–14 ventral segments per annulus at midbody; absence of postmalars; suture between frontals slightly smaller than parietal and nasal sutures; and tail short relative to body length (tail length/body length = 0.10). The new species inhabits the rain forest and small patches of savanna vegetation within the Amazon Forest. A Bayesian analysis based on two mitochondrial (16S and ND2) and three nuclear (cmos, BNDF and RAG1) markers recovered the new species as sister to ...