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1.
Parapharyngodon bainae n. sp. (Nematoda:Pharyngodonidae) collected from the small intestine of Tropidurus torquatus (Squamata:Tropiduridae) is described. The new species is the 47 th species in the genus and the 14 th in the Neotropical region. The morphology of male posterior end, ovary position in females, and egg size can be used to differentiate P. bainae from the other congeneric species. Parapharyngodon rotundatus , Parapharyngodon sanisfaciecaudus , and Parapharyngodon riojensis are most closely related to P. bainae. In males of P. sanisfaciecaudus and P. rotundatus , the cloacal lip has a smooth appearance, whereas in P. bainae , males have an echinate cloacal lip. Parapharyngodon riojensis differs from P. bainae because its females have postbulbar ovaries, the eggs are larger, and the esophagi are larger in both sexes. Parapharyngodon spp. nematodes occupy an intermediate phylogenetic position among pharyngodonid parasite lineages in carnivorous and herbivorous reptiles. The average low intensity of infection for P. bainae (4.8 ± 4.6) is typically found in carnivorous reptiles. This fact and the high prevalence value (60%) can be explained by the ingestion of environmental substrata material containing parasite eggs while foraging.  相似文献   

2.
We studied the ecology of Tropidurus itambere and T. oreadicus that occur syntopically in rocky habitats of Cerrado vegetation in central Brazil during the dry season (April to September 2000). The two species are ecologically similar, but somewhat differentiated in vertical microhabitat use. The two species preferred rocky surface microhabitat. Both species demonstrated a unimodal activity pattern, with a peak between 10 and 15 h. Their diets were similar in composition and prey size. The most frequent item used by both species was ants, whereas the most important preys volumetrically were termites and ants. Small morphological differences observed between the two Tropidurus species could explain minor microhabitat divergence: T. itambere is slightly smaller, heavier, and more robust, and uses lower perches. T. oreadicus is larger, lankier, with longer extremities (tail, fore- and hindlegs), and uses a larger vertical microhabitat range. These ecological differences are slight, when compared with those observed between sympatric species of Tropidurus in spatially more heterogeneous landscapes. Considering the slight ecomorphological divergence between the two Tropidurus species and their high abundance in outcrops, we suggest that interspecific territoriality is the mechanism of coexistence.  相似文献   

3.
The effects of different temperature-acclimations on cellular proliferation and migration were studied in the cerebral cortex of the tropical lizard, Tropidurus hispidus. Lizards were divided in two groups: warm-acclimated lizards (WALs), maintained at the temperature and photoperiod conditions of their natural habitat (mean temperature 26°C; 12:12 light:dark) and the cold-acclimated lizards (CALs), maintained at the same cycle of illumination and a mean temperature of 16°C. Animals were injected with the proliferative marker 5-bromodeoxyuridine (BrdU) and euthanized fifteen or thirty days later for the immunostaining. There was no difference in the number of BrdU-positive nuclei between the experimental groups in any of the cortical layers. In CALs, the positive nuclei were found mostly close to the ependyma, whereas in WALs many positive nuclei were also found in the plexiform and cellular layers of the cortex. In CALs, BrdU-positive nuclei appeared grouped (of 2-3 nuclei), a characteristic not seen in the other group. These data suggest that temperature affects the migrating capability of the newly generated neurons in the lizard cortex, but appears not to interfere with its generation.  相似文献   

4.
Development and differentiation of the reproductive system in lizards begin in the embryonic period, although the stage and time of their occurrence vary according to populations and species. In this study, the events of the development and differentiation of the reproductive system of males and females of Tropidurus catalanensis were characterized during the embryonic, neonatal, and juvenile periods. Embryos at Stages 27, 34, 37, 40, and 41, neonates and juveniles, from Corrientes, Argentina, were analyzed. At Stage 27, the genital ridge was not observed but primordial germ cells were recorded in the yolk sac as well as the mesenteric mesenchyme, indicating the beginning of germ cell migration. Gonadal differentiation commenced at Stage 34. In males from Stage 37, the testes possessed seminiferous cords with Sertoli cells and spermatogonia, while in hatchlings seminiferous tubules and interstitial tissue with mature Leydig cells were present. Spermatogenesis was observed in a specimen of 51.9 mm snout-vent length, corresponding to the minimum reproductive size. In females, from Stage 37 until hatching, the ovaries had a cavernous medulla and a cortex with somatic cells and abundant oogonia. The onset of meiosis and folliculogenesis occurred in the juvenile period.  相似文献   

5.
The helminth community of Tropidurus torquatus (Squamata: Tropiduridae) from a rocky outcrop area located in the state of Minas Gerais, southeastern Brazil, was studied. Ninety-two of the 110 individuals examined (83.6%) harbored helminths. Five species were found, including 3 nematodes ( Physaloptera lutzi , Parapharyngodon bainae , and Oswaldofilaria chabaudi ), 1 unidentified cestode species, and 1 acanthocephalan cystacanth also not identified. Only the nematode species had sufficient data to perform ecological analysis, with P. lutzi exhibiting the highest prevalence (67.3%). Prevalence between male and female hosts differed only for Oswaldofilaria chabaudi , with males exhibiting the highest values. The intensities of infection by P. lutzi and O. chabaudi were different among male and female hosts, with males also exhibiting the highest values. The host body size was positively related to intensity of infection for all nematode species. Local seasonality had some influence on the helminth community structure. Host diet, sexual dimorphism, and behavior (territorialism, forage strategy) represented important factors for the structure of this parasite community. In general, the helminth community was species poor, depauperate, and non-interactive, representing a typical structure observed in lizard hosts.  相似文献   

6.
7.
Allopharynx daileyi n. sp. (Digenea: Plagiorchiidae) from the small intestine of the tropidurid lizard Uranoscodon superciliosus from Amazonian Brazil is described and illustrated. Of the 11 currently recognized species of Allopharynx, we consider Allopharynx megorchis Simha, 1961 a synonym of Allopharynx mehrai (Gogate, 1935) Price 1938 and Allopharynx puertoricensis Acholonu, 1976 a synonym of Allopharynx riopedrensis Garcia-Diaz; thus, A. daileyi becomes the 10th species assigned to the genus. The trematode species Mesocoelium monas and 2 species of Nematoda, Africana chabaudi and Cosmocerca vrcibradici, were also present.  相似文献   

8.
Geographical variation in the degree of thermoregulatory behaviour of the lizard Tropidurus torquatus was studied in 10 restinga populations along approximately 1500 km of Brazilian coast. An index of thermoregulation was estimated using the difference between body and environmental (air and substrate) temperatures and the percentage of negative values for these differences (proportion of body temperatures lower than environmental temperatures). In most populations, the lizards primarily used active thermoregulation, through behavioural means, and mainly in relation to substrate temperatures. Along the restingas, the degree of active thermoregulation increased as a function of the increase in the local environmental temperatures along the restingas. Behavioural thermoregulation of T. torquatus helps the lizards to maintain their body temperatures within an optimal range in which to perform their normal daily activities.  相似文献   

9.
In this study, we used a recently developed supertrees method to test for shared phylogeographical signal in partially overlapping geographical ranges of lizards of the genus Liolaemus from the Andean Range in south-central Chile. We reconstruct mtDNA gene trees for three partially codistributed species ( Liolaemus tenuis, L. lemniscatus and L. pictus ), and our sampling effort is sufficient to allow statistical tests of shared signal between the combinations L. tenuis–L. pictus , and L. tenuis–L. lemniscatus . For both combinations, standardized maximum agreement subtrees scores showed statistically significant signal for shared pattern in regions of overlap, as evaluated by randomization tests ( P <  0.001 and < 0.05, respectively). The matrix representation with parsimony tree obtained from the combination of the three different gene trees revealed concordant phylogeographical associations of all species, and was consistent with the geographical association of intraspecific haploclades with three Chilean bioclimatic zones. A multidimensional scaling analysis of several climate variables showed highly significant differences among these zones, which further suggests that they may have contributed to similar patterns of intraspecific divergence across all three species. In the mesomorphic zone in Central Chile, the species L. tenuis and L. lemniscatus may have codiverged in response to shared orogenic vicariant events, which likely predominated over climatic events associated with cycles of glacial advance and retreat. In the hygromorphic zone in southern Chile, however, glacial cycles likely predominated in structuring the phylogeographical histories of L. tenuis and L. pictus , although important ecological differences between these two caution against broad generalizations at this point.  相似文献   

10.
A new species of Dipsas is described from the Pakaraima Mountains of Guyana. The new species is characterised by 15 dorsal scale rows with the middorsal row slightly enlarged. four pairs of chinshields with the first pair elongate, elongate loreal entering orbit, one preocular, six upper labials, and head narrow anteriorly, increasing in width posteriorly. It could not be determined to which of Peters' (1960) species groups the new species belongs. The new species is known only from 1490 m elevation on Mount Ayanganna. a tepui in the Guiana Shield, where it was found in high-tepui low-canopy habitat, in bromeliads or branches. This is the first record of Dipsas as a member of the Guiana Shield high-tepui herpetofauna.  相似文献   

11.
Based on comprehensive distributional records of the 23 species currently assigned to the lizard genus Tropidurus, we investigated patterns of endemism and area relationships in South America. Two biogeographic methods were applied, Parsimony Analysis of Endemicity (PAE) and Brooks Parsimony Analysis (BPA). Two areas of endemism were detected by PAE: the first within the domains of the semiarid Brazilian Caatinga, which includes seven endemic species, and the second in the region of the Serranía de Huanchaca, eastern Bolivia, in which three endemic species are present. The area cladograms recovered a close relationship between the Atlantic Forest and areas of the South American open corridor. The results revealed a close relationship among the provinces Caatinga (Cerrado, Parana Forest (Pantanal+Chaco)). The uplift of the Brazilian Central Plateau in the Late Pliocene-Early Pleistocene (4-2 Myr BP) has been interpreted as a major event responsible for isolation and differentiation of biotas along these areas. However, we emphasize that without the establishment of a temporal framework concerning the diversification history of Tropidurus it is premature to correlate cladogenetic events with specific time periods or putative vicariant scenarios. The limiting factors hampering the understanding of the biogeographic history of this genus include (1) the absence of temporal references in relation to the diversification of distinct clades within Tropidurus; (2) the lack of an appropriate taxonomic resolution of the species complexes currently represented by widely distributed forms; and (3) the need for a comprehensive phylogenetic hypothesis. We suggest that these three important aspects should be prioritized in future investigations.  相似文献   

12.
We describe Lonchophylla inexpectata sp. n. from the Caatinga of Brazil. This new species can be distinguished from all known species of Lonchophylla that occur in Brazil by dental traits, cranial size, and fur colour. Specimens of Lonchophylla inexpectata have been misidentified as Lonchophylla mordax; but Lonchophylla inexpectata is a pale-venter species, similar in external appearance to Lonchophylla dekeyseri. We have found Lonchophylla inexpectata in the Caatinga of North-eastern Brazil; Lonchophylla mordax along the eastern border of the Caatinga and in the Atlantic Forest–Caatinga ecotone in North-eastern Brazil; and Lonchophylla dekeyseri in the Cerrado of Mid-western Brazil, in the Brazilian Cerrado–Caatinga ecotone, and as far west as the Cerrado of Bolivia.  相似文献   

13.
Based on morphological and genetic evidence we evaluated the taxonomic status of a newly discovered forest-dwelling population of skink(genus Scincella)from the Keo Seima Wildlife Sanctuary, Mondulkiri Province, Cambodia. From phylogenetic analysis of a668-bp fragment of the mt DNA COI and diagnostic morphological characters we allocate the newly discovered population to the Scincella reevesii–S.rufocaudata species complex and describe it as Scincella nigrofasciata sp. nov. The new skink species can be distinguished from all other Southeast Asian congeners by the following combination of morphological characters: snout-vent length(SVL)40.0–52.6 mm; relative tail length(TaL/SVL ratio)1.25–1.94; prefrontals in broad contact; infralabials 6;primary temporals 2; relative forelimb length(FIL/SVL ratio) 0.20–0.22; relative hindlimb length(HIL/SVL ratio) 0.30–0.33; relative forearm length(FoL/SVL ratio) 0.14–0.16; adpressed forelimbs and hind limbs either overlapping(0.4–2.2 mm) or separated(1.9–2.3 mm); midbody scale rows 32–33, paravertebral scales69–74, vertebral scales 65–69; dorsal scales between dorsolateral stripes 8; comparatively slender fingers and toes, subdigital lamellae under fourth toe 15–17;dark discontinuous regular dorsal stripes 5–7; distinct black dorsolateral stripes, narrowing to lateral sides and extending to 52%–86% of total tail length. We provide additional information on the holotype of Scincella rufocaudata(Darevsky Nguyen, 1983), and provide evidence for the species status of Scincella rupicola. Our discovery brings the number of Scincella species in Cambodia to five and emphasizes the incompleteness of knowledge on the herpetofaunal diversity of this country.  相似文献   

14.
Behuria comosa Tavares, Baumgratz & Goldenberg is a new species from Minas Gerais and Espírito Santo, Brazil. It can be recognized by the branch nodes, sinuses of the leaf margins and domatia comose, leaves and inflorescence axes frequently three‐whorled, flowers five(–six)‐merous, calyx lobes broadly triangular and with the apex laterally flattened, and petals glabrous, thickly apiculate. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 489–492.  相似文献   

15.
In a survey of 1,732 amphibians and reptiles collected across S?o Paulo Province, Brazil, and 7 provinces in Paraguay, 26 species were found infected with acanthocephalans. Of 1,510 anurans, 14 anurans, representing 11 species, were infected with cystacanths of Centrorhynchus spp. and 1 anuran with cystacanths of Oligacanthorhynchus sp. Of 107 lizards, 1 lizard was infected with cystacanths of Centrorhynchus sp. and 1 lizard with cystacanths of Oligacanthorhynchus sp. Acanthocephalus caspanensis was found in 3 anurans (3 species) and Acanthocephalus lutzi in 3 anurans (2 species) and 2 snakes (2 species). The systematic position of A. lutzi cannot be resolved using presently available morphological data. Acanthocephalus saopaulensis n. sp. was found in a single individual of Bufo ictericus. The new species can be differentiated from all its congeners except A. caspanensis in having a sigmoid-shaped male posterior end and from A. caspanensis in having a proboscis armature of 16 rows of 5-7 hooks rather than 18-19 rows of 6-7 hooks and larger eggs. The status of Acanthocephalus and Pseudoacanthocephalus continues to be problematic.  相似文献   

16.
17.
Abildgaardia disticha from Estado da Bahia in Brazil is described as new. This species is unique in the tribe Abildgaardieae in having orthodistichous spikelets, and in several respects is intermediate between the subgenera Abildgaardia and Bulbostylis.  相似文献   

18.
Campomanesia espiritosantensis Landrum is described from the coastal forests of Espírito Santo, Brazil. Its relationship to other species in the genus is discussed.  相似文献   

19.
Rosana Romero 《Brittonia》2000,52(2):142-144
A new species of the genusMicrolicia,M. flava, from the highland “campo rupestre” vegetation of Serra da Canastra National Park, São Roque de Minas, Minas Gerais, Brazil, is described and illustrated.  相似文献   

20.
Casearia souzae R.Marquete & Mansano,sp.nov. (S4-1.Fig.1) Type:Brazil.Espírito Santo:(A)guia Branca,Comunidade S(a)o Pedro,propriedade Sr.Jo(a)o Ferreira,Pedra da Bandeira,2008-01-17,M.C.Souza,M.M.Saavedra,R.F.Monteiro & C.N.Fraga 610 (holotype,RB;isotypes,IAC,IBGE,SPF).  相似文献   

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