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The analyses of molecular genetic data (mtDNA markers 16S, ND4, CYTB, and the nuclear marker c-mos) provided evidence that the Asian cat snake taxa Boiga multomaculata and B. ochracea actually represent a single species. They form mixed clades of low intraclade genetic differentiation. This evidence for conspecificy is supported by the lack of differentiation in all examined pholidotic and morphometric characters. Therefore, we formally place Dipsas ochracea Theobald, 1868 in the synonymy of Dipsas multomaculata Boie, 1827. We provide a summary of the tangled taxonomic history of the taxa involved in this study. Also, we resurrect Dipsadomorphus stoliczkae Wall, 1909 from synonymy of B. ochracea, for specimens exhibiting 21 midbody dorsal scale rows. Boiga stoliczkae is found in the Himalayas north and west of the Brahmaputra valley. Finally, based on the detection of historical genetic lineages within the newly defined species Boiga multomaculata we recognize three subspecies: Boiga multomaculata multomaculata (Boie, 1827), Boiga multomaculata ochracea (Theobald, 1868), and Boiga multomaculata septentrionalis n. ssp. which is distributed in northern Myanmar and Assam and Nagaland, India. We designate BMNH 1946.1.2.60 (1) as neotype of Dipsas ochracea Theobald, (2) as lectotype of D. ochraceus Günther, and (3) as lectotype of Boiga ochracea walli Smith, thereby making these names objective synonyms. Finally, we designate BMNH 94.12.31.55 as lectotype of Dipsadomorphus stoliczkae Wall.
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Colubridae , Lagartos , Animales , Colubridae/genética , Ambiente , FilogeniaRESUMEN
We describe two new species of Draconura-clade semiaquatic anoles from the central Pacific versant of Costa Rica. The two new species are similar to Anolis aquaticus in external appearance and ecology but differ from this species in male dewlap coloration and scalation. Anolis robinsoni sp. nov. and A. riparius sp. nov. differ from each other mainly in male dewlap color. All three species are distinct according to diagnostic morphological traits and a phylogenetic analysis of mitochondrial DNA sequences (669 bases of COI gene). We discuss the distribution and ecology of Anolis aquaticus and the new species.
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Background: The aquatic snakes of the genus Helicops are widely distributed throughout northern South America, but understudied concerning some aspects, including morphological traits and distribution. The most recent publication that provided an identification key to all species of Helicops is over 50 years old. This key is of limited value today since it includes taxa no longer recognised and lacks 8 of the 19 species currently recognised. There never was a publication trying to summarise distributional and morphological information of all species of Helicops. Most knowledge of these species is distributed throughout many small publications, such as short observation notes. New information: Here, we present distribution maps (point records), an identification key and comments on identification for all species in this genus. We base our results on a comprehensive literature review of over 300 scientific publications and own examinations. Our examinations comprise 190 specimens of 10 of the 19 currently recognised species and one Helicops sp. We report range extensions for the species H.danieli, H.infrataeniatus, H.leopardinus, H.pastazae and H.polylepis.
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Rough-skinned newts, Taricha granulosa, which contain tetrodotoxin (TTX), a potent neurotoxin, are widely distributed along the west-coast of North America up to British Columbia (BC), Canada, and Southeast Alaska. Their genetic population structure using DNA-microsatellites and the TTX-content of specimens from British Columbia (Prince Rupert area) and Alaska (Revillagigedo Island, Shelter Island, and Juneau) were analysed. TTX-concentrations were low in newts from BC and Revillagigedo Island, but high in specimens from mainland Juneau, which had been deliberately introduced from Shelter Island, where TTX was not detectable in the individuals sampled. No significant genetic differences were detected between these populations, which may correlate with the high intraspecies variability of TTX. It is still an open question, which factors favour or induce the toxin production in the newts.
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Salamandridae , Animales , Humanos , América del Norte , Salamandridae/genética , TetrodotoxinaRESUMEN
Based on two male and two female individuals, we describe a new genus and species of mud snake, Myanophis thanlyinensis gen. nov., sp. nov., from the vicinity of the campus of East Yangon University, Yangon, Thanlyin, Myanmar. This species differs from every other homalopsid species by the following combination of characters: (1) dorsal scales smooth, row formula 21-21-19 or 21-21-17; (2) tail short, ratio tail length/SVL 0.185-0.204 in males, 0.160-0.167 in females; (3) nasal scales separated; (4) 125-126 ventral scales in males, 120-122 in females; (5) 38-39 subcaudal scales in males, 32-34 in females; and (6) hemipenis bilobed. Its matrilineal genealogy (based on analyses of 16S and cytochrome b sequences), associates Myanophis thanlyinensis gen. nov., sp. nov. most closely with species of the genera Myrrophis and Gyiophis. The new taxon differs from the species of Myrrophis and Gyiophis by having a bilobed hemipenis (vs. unilobed). Myanophis thanlyinensis gen. nov., sp. nov. differs further from the species of Myrrophis by having 125-126 ventral scales in males and 120-122 in females (vs. 137-162 and 137-164, respectively), and 38-39 subcaudal scales in males and 32-34 in females (vs. 39-55 and 37-52, respectively). Myanophis thanlyinensis gen. nov., sp. nov. differs further from the species of Gyiophis by lacking dark blotches along flank (vs. present), and by having 21 dorsal scales rows at midbody (vs. 25). We provide an identification key to the homalopsid species known to occur in Myanmar. As a novelty to the classic holotype description and characterization, the individual has been genome sequenced by Illumina short-read technology and its genome has been assembled into a draft nuclear genome and a complete, annotated mitochondrial genome. This innovative approach comprehensively and permanently characterizes the genomic variation of the holotype.
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Ecosistema , Lagartos , Distribución Animal , Estructuras Animales , Animales , Femenino , Masculino , Mianmar , FilogeniaRESUMEN
Based on its mandibular gland secretion, the earless monitor lizard, Lanthanotus borneensis, has been considered a venomous animal like other members of the Toxicofera group, including Heloderma. In the present study, the gland structure and teeth of L. borneensis were examined by micro-tomography (µCT) and scanning electron microscopy (SEM), respectively, and proteomic analysis of the gland extract was performed. The mandibular gland consists of six compartments with separate ducts. The pleurodont teeth of the lower and upper jaw are not grooved but possess a sharp ridge on the anterior surface. Proteomic analysis of the gland extract confirmed previous studies that kallikrein enzymes are the major biologically active components. In view of the lizard's biology, its mandibular gland secretion is obviously not needed for prey capture or defence. It seems not justified the labelling of L. borneensis as a venomous animal. However, definitively answering this question requires toxinological studies on natural prey.
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Lagartos , Ponzoñas , Animales , Calicreínas , Proteómica , DienteRESUMEN
A new species of gecko of the genus Hemidactylus (Squamata: Gekkonidae) is described from São Nicolau Island, Cabo Verde Archipelago, and the Sal and Boavista island populations of Hemidactylus boavistensis (i.e., Hemidactylus boavistensis boavistensis comb. nov. and Hemidactylus boavistensis chevalieri comb. nov.) are recognized as subspecies. Hemidactylus nicolauensis sp. nov. is genetically distinct from H. bouvieri, to which it has previously been referred, and from all other closely related endemic Hemidactylus from Cabo Verde Islands in mitochondrial (12S cyt b) and nuclear (RAG2, MC1R) markers. It is characterized morphologically by its distinct colouration and a diagnostically different arrangement of digital lamellae. With the description of this new species, São Nicolau is now known to harbour three single-island endemic gecko species, and the documented reptile diversity in Cabo Verde is raised to 23 endemic species. As a result of our taxonomic changes, existing conservation regulations should be updated and the conservation status of these taxa should be re-evaluated.
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Lagartos , Animales , Cabo Verde , Islas , Mitocondrias , FilogeniaRESUMEN
We present information on primary type specimens for 13,282 species and subspecies of reptiles compiled in the Reptile Database, that is, holotypes, neotypes, lectotypes, and syntypes. These represent 99.4% of all 13,361 currently recognized taxa (11,050 species and 2311 subspecies). Type specimens of 653 taxa (4.9%) are either lost or not located, were never designated, or we did not find any information about them. 51 species are based on iconotypes. To map all types to physical collections we have consolidated all synonymous and ambiguous collection acronyms into an unambiguous list of 364 collections holding these primary types. The 10 largest collections possess more than 50% of all (primary) reptile types, the 36 largest collections possess more than 10,000 types and the largest 73 collections possess over 90% of all types. Of the 364 collections, 107 hold type specimens of only 1 species or subspecies. Dozens of types are still in private collections. In order to increase their utility, we recommend that the description of type specimens be supplemented with data from high-resolution images and CT-scans, and clear links to tissue samples and DNA sequence data (when available). We request members of the herpetological community provide us with any missing type information to complete the list.
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Reptiles , Animales , Bases de Datos FactualesRESUMEN
We describe the new species Norops arenal sp. nov. from Parque Nacional Volcán Arenal, north-central Costa Rica. In external morphology and genetic similarity of the 16S DNA barcode, Norops arenal is most similar to N. altae, N. fortunensis, N. fuscoauratus, N. gruuo, N. kemptoni, N. monteverde, N. pseudokemptoni, and N. tenorioensis. In morphology it shares with these species the following characteristics: (1) short hind limbs; (2) a single elongate prenasal scale; (3) tiny, smooth, often juxtaposed body scales; and (4) a slender habitus, often delicate. Norops arenal differs from these species, among several scalation details, by having a blackish central area in the male dewlap in life and in preservative (vs. no suffusion of black pigment on male dewlap in the other species), and a small red female dewlap in life (vs. dirty white, cream colored, or orange); extremely short hind legs with the tip of fourth toe of the adpressed hind leg reaching only to level of shoulder (vs. usually at least to level of ear in the other species); a short tail with a tail length/SVL ratio of 1.53 in single specimen with complete tail (vs. this ratio >1.6 in the other species); and a tiny size with 41.5 mm in single known adult male and 38.5 mm in single known adult female (vs. SVL of adults usually >42.0 mm). It further differs from N. altae, N. fuscoauratus, N. gruuo, N. pseudokemptoni, and N. tenorioensis by having a unilobed hemipenis (vs. bilobed in these five species).
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Lagartos , Animales , Costa Rica , Femenino , MasculinoRESUMEN
Single-locus molecular barcoding is a useful method for identifying overlooked and undescribed biodiversity, providing the groundwork for further systematic study and taxonomic investigation. A variety of methods for delimiting species from barcoding libraries have been developed and applied, allowing for rapid estimates of species diversity in a broad range of taxa. However, tree-based and distance-based analyses can infer different group assignments, potentially over- or underestimating the number of putative species groups. Here, we explore diversity of mainland species of anole lizards from the Chortís Block biogeographical province of northern Central America using a DNA barcoding approach, generating and analyzing cytochrome oxidase subunit I (COI) sequences for over 400 samples assignable to 33 of 38 (86.8%) native and one introduced mainland species. We subsequently tested the effects different models of nucleotide substitution, different species-delimitation algorithms, and reducing our dataset had on species delimitation estimates. We performed of two distance-based (ABGD, RESL) and three tree-based (bPTP, mPTP, GMYC) analyses on both the full dataset and a dataset consisting only of unique halotypes. From 34 nominal taxa, analyses of the full dataset recovered between 34 and 64 operational taxonomic units (OTUs), while analyses of the reduced dataset inferred between 36 and 59. Reassigning individuals to either mPTP-inferred or ABGD clustered (7.2% threshold) groups improved the detection of a barcoding gap across three different models of nucleotide substitution, removing overlap between intra- and interspecific distances. Our results highlight the underestimated diversity of mainland Chortís Block anoles, but the lack of congruence between analyses demonstrates the importance of considering multiple analytical methods when dealing with single-locus datasets. We recommend future studies consider the effects of different models of nucleotide substitution on proposed barcoding gaps, as well as the effect reducing a dataset to unique haplotypes may have on proposed diversity estimates.
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Frogs of the family Dendrobatidae are known to contain toxic alkaloids in their skin secretion, but Allobates species of the closely related Aromobatidae family are considered to lack toxic secretions. However, contradictory results have been reported. Analyses of alcohol extracts from three different Allobates species from South-America (Guiana Shield), Central America (Costa Rica), and from the dendrobatid frog Silverstoneia flotator confirm the absence of alkaloids and tetrodotoxin in aromobatids and in a dendrobatid of the subfamily Colostethinae.
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Alcaloides/análisis , Anuros , Tetrodotoxina/análisis , Animales , Costa Rica , Guyana , Piel/químicaRESUMEN
Adaptive radiation is a widely recognized pattern of evolution wherein substantial phenotypic change accompanies rapid speciation. Adaptive radiation may be triggered by environmental opportunities resulting from dispersal to new areas or via the evolution of traits, called key innovations, that allow for invasion of new niches. Species sampling is a known source of bias in many comparative analyses, yet classic adaptive radiations have not been studied comparatively with comprehensively sampled phylogenies. In this study, we use unprecedented comprehensive phylogenetic sampling of Anolis lizard species to examine comparative evolution in this well-studied adaptive radiation. We compare adaptive radiation models within Anolis and in the Anolis clade and a potential sister lineage, the Corytophanidae. We find evidence for island (i.e., opportunity) effects and no evidence for trait (i.e., key innovation) effects causing accelerated body size evolution within Anolis. However, island effects are scale dependent: when Anolis and Corytophanidae are analyzed together, no island effect is evident. We find no evidence for an island effect on speciation rate and tenuous evidence for greater speciation rate due to trait effects. These results suggest the need for precision in treatments of classic adaptive radiations such as Anolis and further refinement of the concept of adaptive radiation.
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Adaptación Biológica , Especiación Genética , Lagartos/genética , Animales , FilogeografíaRESUMEN
Tropidurus is a Neotropical genus of iguanoid lizards characterized by a conspicuously enlarged interparietal plate, the presence of gular folds, presence of infradigital keels, and the absence of femoral pores. Currently, 29 species are recognized within the genus, seven of which are present in Paraguay: T. etheridgei, T. torquatus, T. guarani, T. lagunablanca, T. spinulosus, T. tarara, and T. teyumirim. We generated genetic data based on two DNA mitochondrial markers (16S and COI) and one nuclear (PRLR) marker for all the seven Paraguayan species with the goal to identify the taxonomic relationships among taxa based on the intra- and interspecific genetic variation and the construction of molecular clusters. ML and BI analyses match in the recognition of two main clusters: groups torquatus and spinulosus, and within the torquatus group the differentiation between T. catalanensis and T. etheridgei is highly supported. Nevertheless, there is a complete lack of congruence between mitochondrial and nuclear genes in the topology within the spinulosus group. Tropidurus guarani and T. spinulosus are more differentiated from the remaining species of the spinulosus group with genetic p-distances from 4.0 to 6.0. Low distances were found between T. lagunablanca and T. tarara (1.0-1.1%), and slightly higher, among T. teyumirim, T. lagunablanca, and T. tarara (2.0-2.6% respectively). From a morphological perspective, species of the Tropidurus torquatus group are easily distinguished; but we found strong overlaps of scalation characters in the spinulosus group. We interpret the low genetic distances documented among the nominal taxa Tropidurus lagunablanca, T. tarara, and T. teyumirim as evidence for conspecificity. This hypothesis is supported by the lack of morphological characters that would diagnose any of the three taxa. Similarly, we found low genetic distances among populations assigned to the nominal taxa T. guarani and T. spinulosus, including samples from near the type locality of the former, and therefore we recognize only two species of the T. spinulosus complex in Paraguay: T. spinulosus and T. lagunablanca.
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Lagartos , Animales , Variación Genética , Paraguay , FilogeniaRESUMEN
The pineal and parapineal organs are dorsal outpocketings of the vertebrate diencephalon that play key roles in orientation and in circadian and annual cycles. Lampreys are four eyed in that both the pineal and parapineal form eyelike photosensory structures, but the pineal is the dominant or sole median photosensory structure in most lower vertebrate clades. The pineal complex has been thought to evolve in a single direction by losing photosensory and augmenting secretory function in the transitions from three-eyed lower vertebrates to two-eyed mammals and archosaurs [1-3]. Yet the widely accepted elaboration of the parapineal instead of the pineal as the primary median photosensory organ [4] in Lepidosauria (lizards, snakes, and tuataras) hints at a more complex evolutionary history. Here we present evidence that a fourth eye re-evolved from the pineal organ at least once within vertebrates, specifically in an extinct monitor lizard, Saniwa ensidens, in which pineal and parapineal eyes were present simultaneously. The tandem midline location of these structures confirms in a striking fashion the proposed homology of the parietal eye with the parapineal organ and refutes the classical model of pineal bilaterality. It furthermore raises questions about the evolution and functional interpretation of the median photosensory organ in other tetrapod clades.
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Evolución Biológica , Ojo/anatomía & histología , Lagartos/anatomía & histología , Lagartos/fisiología , Glándula Pineal/anatomía & histología , Glándula Pineal/fisiología , Animales , FilogeniaRESUMEN
Homonota is a Neotropical genus of nocturnal lizards characterized by the following combination of characters: absence of femoral pores, infradigital lamellae not dilated, claws without sheath, inferior lamellae laterally not denticulate, and presence of a ceratobranchial groove. Currently the genus is composed of 10 species assembled in three groups: two groups with four species, and the fasciata group with only two species. Here, we analyzed genetic and morphologic data of samples of Homonota fasciata from Paraguay; according to Maximum Likelihood and Bayesian inference analyses, the Paraguay population represents an undescribed species. Additionally, morphological analysis of the holotype of H. fasciata (MNHN 6756) shows that it is morphologically different from the banded, large-scaled Homonota commonly referred to as "H. fasciata". Given the inconsistency between morphological characters of the name-bearing type of H. fasciata and the species commonly referred to as H. fasciata, we consider them as different taxa. Thus, H. fasciata is a species inquirenda which needs further studies, and we resurrect the name H. horrida for the banded, large-scaled Homonota. The undescribed species from Paraguay is similar to H. horrida, but can be differentiated by the high position of the auditory meatus relative to the mouth commissure (vs. low position in H. horrida); and less developed tubercles on the sides of the head, including a narrow area between the orbit and the auditory meatus covered with small granular scales with or without few tubercles (vs. several big tubercles on the sides of the head even in the area between the orbit and the auditory meatus). The new species is distributed in the Dry Chaco in South America. With the formal description of this species, the actual diversity of the genus Homonota is increased to 12 species. Furthermore, we infer phylogenetic relationships for 11 of the 12 described species of the genus, based on 11 molecular markers (two mitochondrial and nine nuclear genes), with concatenated and species tree approaches.
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The family Gymnophthalmidae contains nearly 235 species with a distribution range from southern Mexico to central Argentina as well as in the Antilles. Among gymnophthalmids, the genus Colobosaura is a member of the tribe Iphisini, and currently is considered monotypic (C. modesta). The diversity of the tribe was studied recently, with the erection of several new genera. In this work genetic and morphological data of specimens of Colobosaura recently collected in Paraguay were analyzed. Genetic (16S barcode) data indicate that these samples are not conspecific with C. modesta and they are allocated to the nominal species C. kraepelini. Because the original primary type of the latter taxon is considered to be lost, a neotype (SMF 101370) is designated for this species and a redescription provided based on our material. Colobosaura kraepelini is distributed in the Humid Chaco, being the only member of the whole tribe in this ecoregion.
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Anolis lizards (anoles) are textbook study organisms in evolution and ecology. Although several topics in evolutionary biology have been elucidated by the study of anoles, progress in some areas has been hampered by limited phylogenetic information on this group. Here, we present a phylogenetic analysis of all 379 extant species of Anolis, with new phylogenetic data for 139 species including new DNA data for 101 species. We use the resulting estimates as a basis for defining anole clade names under the principles of phylogenetic nomenclature and to examine the biogeographic history of anoles. Our new taxonomic treatment achieves the supposed advantages of recent subdivisions of anoles that employed ranked Linnaean-based nomenclature while avoiding the pitfalls of those approaches regarding artificial constraints imposed by ranks. Our biogeographic analyses demonstrate complexity in the dispersal history of anoles, including multiple crossings of the Isthmus of Panama, two invasions of the Caribbean, single invasions to Jamaica and Cuba, and a single evolutionary dispersal from the Caribbean to the mainland that resulted in substantial anole diversity. Our comprehensive phylogenetic estimate of anoles should prove useful for rigorous testing of many comparative evolutionary hypotheses. [Anoles; biogeography; lizards; Neotropics; phylogeny; taxonomy].
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Clasificación , Lagartos/clasificación , Filogenia , Américas , Distribución Animal , Animales , Biodiversidad , Región del Caribe , Lagartos/genética , FilogeografíaRESUMEN
The lizard genus Teius is composed by three species: Teius teyou, T. oculatus, and T. suquiensis and is distributed in South America, east of Andes. Teius teyou and T. oculatus have wide parapatric distributions with contact zones. Teius suquiensis is present in a small range along a sympatric area of the former species. In this work we analyze the distribution of the three species of Teius across its whole geographic range, examining its relationships with climatic parameters. We based our analysis on specimens in collections and literature records. Our analysis shows that the genus Teius is distributed from central Bolivia southwards to north of Río Negro Province in northern Patagonia, Argentina. Teius teyou reaches the northernmost range limit of the genus whereas T. oculatus occupies the southernmost limit. Teius oculatus is related to open and moist environments whereas T. teyou is more adapted to xeric and forested areas. Teius suquiensis is present in xerophytic areas of Dry Chaco and Espinal. Climatic factors in the distribution of the distribution of the two widespread species show marked differences and seasonality.
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Distribución Animal , Lagartos/fisiología , Animales , Ecosistema , Lagartos/clasificación , América del SurRESUMEN
We describe a new species of Leiocephalus from the coastal dunes of Bahía de las Calderas in the southwestern Dominican Republic. In external morphology, Leiocephalus sixtoi sp. nov. is most similar to L. schreibersii and L. inaguae. Leiocephalus sixtoi differs from L. inaguae in having a U-shaped bony parietal table (vs. V-shaped in L. inaguae), 3 or 4 enlarged postcloacal scales in males (vs. 2 in L. inaguae), most scales on snout posterior to internasal scales rugose to keeled scales (vs. smooth in L. inaguae), and a patternless throat in males, spots on the throat in females (vs. throat with dark streaks and bars in males and females of L. inaguae). Leiocephalus sixtoi differs from L. schreibersii in having the scales of the lateral fold only slightly smaller than adjacent scales (vs. scales of lateral fold distinctly smaller than adjacent scales), having prominent caudal crest scales in adult males (vs. caudal crest scales of moderate size, even in very large males in L. schreibersii), a pattern of dark gray bars on a grayish brown background in the region above the lateral body fold (vs. dense turquoise blue mottling with heavy suffusion of red pigment in L. schreibersii), a darker dorsal ground color (vs. paler in L. schreibersii), and a red iris in adult males (vs. pale grayish blue in adult male L. schreibersii). Leiocephalus sixtoi differs further from L. schreibersii in several osteological characters as follows: in L. sixtoi the nasal process of the premaxilla reaches to mid-level of the bony external nares (vs. to level of posterior margin of the bony external nares in L. schreibersii), lacking a constriction at the base of the nasal process of the premaxilla (vs. such a constriction present in L. schreibersii), and having a reduced nasal-prefrontal contact leaving the nasal processes of the frontal bone exposed (vs. nasal and prefrontal bones contact one another, thereby obscuring the nasal processes of the frontal bone in L. schreibersii). We designate SMF 26228, an adult male from Saint Marc, Province Artibonite, Haiti, as the neotype of L. schreibersii.
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Lagartos/anatomía & histología , Lagartos/clasificación , Animales , República Dominicana , Femenino , Geografía , Haití , Lagartos/genética , Masculino , Osteología , Filogenia , PigmentaciónRESUMEN
Giant anoles of the genus Dactyloa have been considered to be represented in eastern Panama by six species. In this contribution, we describe a seventh species that is restricted to the Majé, San Blas, Darién, and Piedras-Pacora mountain ranges. The new species resembles D. ibanezi, D. limon, and D. purpurescens in external morphology but differs from these species in dewlap coloration, dorsal color pattern, morphometrics, and scalation. The recognition of the new species is further supported by DNA barcoding (genetic distances >2.7% in 16S and >7.8% in COI between the new species and all other species of Dactyloa). We discuss the taxonomic identity of D. purpurescens, and, based on morphological evidence, we place D. chocorum in the synonymy of the former species. An identification key for all 11 Dactyloa species occurring in Panama is provided.