New Species Of Atractus Research Articles

A new species of groundsnake genus Atractus Wagler, 1828 (Serpentes, Dipsadidae) from the Peruvian Andes revealed by unequivocal morphological characters

Based on an exhaustive revision of external morphological characters we describe a new species ofAtractusfrom the humid montane forest of the Andes of northern Peru, Cajamarca department, occurring at elevations of 1641 to 2161 m. This new species was misidentified asA. gigasin the literature and for more than a decade represented the southernmost record of the that species. In the absence of molecular data and limited by a small sample, we use some underreported characters in the genusAtractussuch as the presence of apical pits. Thus, the combination of apical pits as well as other characters mentioned in the literature (i.e., head scutellation and number of subcaudals) distinguishes the Peruvian population fromA. gigas, and strongly supports the morphological separation of this taxon from the rest of its congeners.

Redescription ofAtractus punctiventrisand Description of Two NewAtractus(Serpentes: Dipsadidae) from Brazilian Amazonia

Abstract: We redescribe Atractus punctiventris based on the examination of its holotype, two topotypes, and two additional specimens recently collected. We describe two new species of Atractus with 15 dorsal scale rows, previously confused with Atractus insipidus, from the eastern and western portions of Brazilian Amazonia, respectively. The new species are recognized on the basis of unique combinations of morphological characters. We compare Atractus punctiventris and the two new species with all congeners from most lowland provinces of cis-Andean South America. We discuss potential affinities of the three species, mainly by sharing exclusive hemipenial traits with congeners placed in different phenetic groups, and allocate them to distinct species groups of Atractus.

Two new species of Atractus from Colombia (Reptilia, Squamata, Dipsadidae)

We describe two new species of Atractus from Colombia: one from the Serrania de la Lindosa, south of San José de Guaviare in the province Guaviare, and another from Punta de Betin in the province Magdalena, close to the Caribbean coast. The first new species differs from all congeners by having a combination of 17 smooth dorsal scale rows; loreal present, approximately as long as high; temporals 1+2; seven supralabials; seven infralabials; five maxillary teeth; four gular scale rows; four pre-ventrals; 187 ventrals in single male; 29/31 subcaudals in single male; dorsum of body with longitudinal stripes; venter uniformly dark gray. The second new species differs from all congeners by having a combination of 17 smooth dorsal scale rows; loreal absent; temporals 1+2; seven supralabials; six or seven infralabials; eight maxillary teeth; three gular scale rows; three pre-ventrals; 146 ventrals in single male; 31/32 subcaudals in single male; dorsum of body and tail reddish brown with paired, occasionally slightly alternating lateral vertical cream blotches, approximately one dorsal scale broad, not contacting in vertebral region; venter cream with reddish brown blotches, forming two parallel series on anterior body and a checkered pattern on the rest of body.

A New Species ofAtractus(Serpentes: Dipsadidae) from the Andes of Ecuador

Abstract: A new species of Atractus is described from cloud forests of the extreme northern Ecuadorian Andes, Tulcan County, Carchi Province. Atractus savagei sp. nov. is distinguished from all congeners by the combination of 17 dorsal scale rows, long loreal, six supralabials (third and fourth contacting orbit), seven infralabials (first four contacting chinshields), 5–8 maxillary teeth, 161–165 ventrals in females and 149–154 in males, 23–26 subcaudals in females and 28–33 in males, a brown dorsum with black specks on the margins of scales, two black longitudinal stripes on each side of the body, yellow ventral color of head gradually changing to orange and red toward the back of the body, venter with lateral and median series of black blotches arranged in conspicuous longitudinal stripes, moderate body size, a long tail in males, and a moderately bilobed, barely capitate, and slightly calyculate hemipenis. Based on shared morphological characters, especially hemipenial features, we propose to tentativ...

A new giant Atractus (Serpentes: Dipsadidae) from Ecuador, with notes on some other large Amazonian congeners.

We describe a new species of Atractus from Cordillera de los Guacamayos in the Andes of Ecuador. This new species is the largest known species of Atractus, reaching almost 120 cm in total length with a robust habitus. We also use multivariate statistical analyses of morphometric data to look into the taxonomic confusion involving other large, banded/blotched, species of Atractus in Western Amazonia. We show that A. snethlageae has a widespread distribution in Amazonia and has been repeatedly confused with A. major in Ecuador owing to its color polymorphism. Our multivariate statistical analyses support previous suggestions to recognize A. snethlageae as a distinct species relative to A. flammigerus. Taxonomic accounts are provided for both A. major and A. snethlageae including detailed color pattern descriptions. We also find that there are no valid morphological differences to support recognizing A. arangoi as a separate species from A. major; consequently we synonymize the former name with the latter.

A new species of Atractus (Serpentes: Dipsadidae) from Serra do Cipó, Espinhaço Range, Southeastern Brazil, with proposition of a new species group to the genus

We describe a new species of Atractus from Serra do Cipó, at the southeastern versant of Serra do Espinhaço, an inland mountain range nearly parallel to the Brazilian Atlantic coast. The new species is morphologically similar to A. paraguayensis and A. potschi with which it shares: 15 dorsal scale rows; white occipital region in juvenile specimens; dorsal ground color reddish pink to red (in life) with alternate black transversal spots, blotches or transversal bands; seven upper and lower labial scales; ventrals and subcaudals creamish white; hemipenis slightly bilobed, semicapitate and semicalyculate. The new species differs from both taxa mainly on the basis of exclusive coloration characters (number and shape of transversal bands) and hemipenial morphology (median face of the lobes without ornamentation), besides punctual meristic (number of ventral scales and maxillary teeth) and morphometric (adult snout-vent length) differences. Finally, we provide a discussion regarding the potential affinities of the new species and we redefine some Atractus species groups in order to better accommodate species sharing unique combinations of morphological characters.

Pacific lowland snakes of the genus Atractus (Serpentes: Dipsadidae), with description of three new species

The taxonomic status of the Pacific lowland Atractus is revised on the basis of meristic, morphometric, colour pattern, and hemipenial characters. Geographical variation is reported for six Atractus species (A. boulengerii, A. clarki, A. iridescens, A. melas, A. multicinctus, and A. paucidens). Atractus boulengerii is rediscovered and redescribed from a specimen from the Colombian coast. The first voucher specimens are reported for A. melas. The current status of A. microrhynchus is maintained based on the discovery of new material referrable to that species. Three new species of Atractus are described from the Pacific lowland of Colombia: A. echidna sp. nov., A. medusa sp. nov., A. typhon sp. nov. Two new Atractus species groups (multicinctus and paucidens) are proposed based on external morphology, maxillary dentition, and hemipenial characters. A new key to Pacific lowland species of Atractus is provided.

Three New Atractus (Serpentes: Dipsadidae) from the Andes of Colombia

Three new species of Atractus are described from the northern Cordillera Central of Colombia. The new species, previously confused with older names, are easily distinguished from any currently recognized Atractus by unique combinations of morphological characters. Additionally, we provide comments on the Atractus diversity and distribution pattern in the Colombian Andes.

Description of two new species from Venezuela in the highly diverse dipsadine genus Atractus (Serpentes: Colubridae)

Abstract Two new species of Atractus are described from Venezuela uplands and highlands on two northern Andean cordilleras. Atractus acheronius, known only from Sierra de Perijá, can be distinguished from congeners by having 17 dorsal scale rows, presence of preocular scales, seven upper and lower labials, seven maxillary teeth, 166 ventrals in the single female, 23 subcaudals, dorsum brown with small dark brown dots, large body size, huge body diameter, and small tail size. Atractus multidentatus, known only from north versant of the Cordillera de Mérida, can be distinguished from congeners by having 17 dorsal scale rows, eight upper and lower labials, 18 maxillary teeth, 153 ventrals in the single female, nine subcaudals, dorsum reddish brown with five longitudinal dark brown stripes, small body size, small body diameter, and small tail size. Additionally, a discussion concerning the species description of Atractus based on unique specimens is provided.

A new species of the colubrid snake genus Atractus (Reptilia: Serpentes) from the central Amazon of Brazil

A new species of Atractus is described from upper Cururu River in the Amazon Basin of Brazil. The new species differs from all currently recognized Atractus by having a dorsal colour pattern reddish brown, with first two dorsal scale rows creamish white, hemipenis slightly bilobed, with alary spines at intrasulcar region, and lateral projections of the lobes depressed in their basal portions. In addition, a discussion concerning putative close relative taxa is provided.

New Species of Atractus Wagler, 1828 (Serpentes: Dipsadinae) from Guyana Plateau in Northern Brazil

A new species of Atractus is described from Serra do Surucucu, a mountain slope at 1,000 m in the Guyana Shield, State of Roraima, Brazil. This species, only known by females, is diagnosed from all congeners by the following combination of characters: 17/17/17 smooth dorsal scale rows, without apical pits; 200–207 ventral scales; 25–26 subcaudal scales; moderate sized loreal, contacting second and third supralabials; seven supralabials, third and fourth contacting orbit; seven infralabials, first three contacting chinshields; moderate size, 222–388 mm SVL; short tail (7.7–8.8% snout–vent length); dorsal color pattern, in preservative, uniform chocolate to dark brown, with two conspicuous light paraventral lines, and a light incomplete occipital collar; venter immaculate creamish-white; tail uniform black; five maxillary teeth. We compared the new species with all currently recognized cis-Andean Atractus, and its affinities with Atractus alphonsehogei, Atractus caxiuana, Atractus collaris, Atractus gaigeae, Atractus limitaneus, and Atractus zidoki are discussed on the basis of putative morphological synapomorphies.

A New Species of Atractus (Serpentes: Dipsadinae) from a Relictual Forest in Northeastern Brazil

A new species of Atractus is described from Serra de Baturité, an Atlantic Forest enclave in the semiarid Caatinga of the state of Ceará, northeastern Brazil. The new species is distinguished from all congeners by the combination of 17 dorsal scale rows at midbody, long loreal, two postoculars, seven upper and lower labials, first four infralabials in contact with chinshields, seven maxillary teeth, moderate body and tail sizes, slightly bilobed and semicapitate hemipenis with lateral-tip projections, light dorsal color pattern uniformly scattered with small dark brown dots, and ventral color pattern uniformly creamish white. The new species shares most of the external morphology and hemipenis characters with A. pantostictus, differing from this taxon by general color pattern and number of subcaudal scales.

A NEW SPECIES OF ATRACTUS (SERPENTES: COLUBRIDAE: DIPSADINAE) FROM THE ATLANTIC FOREST OF ALTO PARANÁ, PARAGUAY

We here describe a new species of Atractus from the Atlantic Forest of Alto Paraná Paraguay. The new species differs from other Atractus by the combination of the following characters: 17 dorsal scale rows without reduction, six supralabial and infralabial scales, only one post-ocular, a uniformly gray dorsum and a whitish belly with iridescent tonalities. The new species of Atractus is known only by the holotype which is a female specimen, and two paratypes. This is the third species of the genus recorded in Paraguay. Given the current status of the Atlantic Forest in Paraguay and in South America, the present species might be classified as highly threatened.

A NEW SPECIES OF ATRACTUS (SERPENTES: COLUBRIDAE) FROM SOUTHERN BRAZIL

A new species of Atractus is described from grasslands of the State of Rio Grande do Sul, southern Brazil. The new species is distinguished from all congeners by the combination of a single postocular, long loreal, six supralabials, generally six infralabials, 17 dorsal scales rows, six or seven maxillary teeth, and a dorsal color pattern in preservative uniformly grayish-brown with a creamish-white temporal region. Comparisons of the new species are made with all other Atractus species, and its affinities with A. reticulatus and allied species are suggested based on the morphology of the hemipenis.

A New Species and a New Record of Atractus (Serpentes: Colubridae) from the Andes of Venezuela

A new species of Atractus is described from the Cordillera de Merida, Venezuela. The new species can be distinguished from all other congeners by the combination of 15 dorsal scale rows at midbody and a color pattern consisting of two pale dorsolateral stripes on a dark ground color. Additionally Atractus pamplonensis is reported for the first time for Venezuela.

A New Species of Snake in the Genus Atractus (Colubridae: Xenodontinae) from Northeastern Brazil

A New Species of Snake in the Genus Atractus (Colubridae: Xenodontinae) from Northeastern Brazil