S. V. Brito

Helminths and Pentastomida of two synanthropic gecko lizards, Hemidactylus mabouia and Phyllopezus pollicaris, in an urban area in Northeastern Brazil.

Helminths and pentastomids were examined in exotic Hemidactylus mabouia and native Phyllopezus pollicaris lizards, living synanthropically in an urban area in the municipality of Crato, Ceará state, northeastern Brazil. A total of 194 lizards were collected, being 76 specimens of H. mabouia e 118 specimens of P. pollicaris. Six parasite species were found infecting H. mabouia: the cestode Oochoristica sp., the nematodes Parapharyngodon sceleratus, Physaloptera retusa, Physalopteroides venancioi, and Spauligodon oxkutzcabiensis and the pentastomid Raillietiella mottae; while four parasite species were found associated with P. pollicaris: Oochoristica sp., P. sceleratus, P. retusa, and S. oxkutzcabiensis. Three new host records were reported: P. retusa infecting H. mabouia and P. retusa and Oochoristica sp. infecting P. pollicaris. About 75% of the parasites species found were shared by both lizards. Moreover, H. mabouia showed greater diversity than P. pollicaris (6 versus 4 species), while P. pollicaris had higher intensity of infection than H. mabouia (1536 versus 121 specimens).

Parasitic nematodes of Polychrus acutirostris (Polychrotidae) in the Caatinga biome, Northeastern Brazil

We present data on nematode infracommunity of the arboreal lizard Polycrhus acutirostris in the semiarid Caatinga biome, northeastern Brazil. Twenty- twolizard specimens collected in the municipality of Várzea Alegre in Ceará State and in the municipality of Exu in Pernambuco State were analyzed. Two species of nematodes were found, an Oxyuridae, Gynaecometra bahiensis, which had a mean intensity of infection 23.5 ± 5.8 (prevalence 22%) and a Physalopteridae, Physaloptera retusa which had infection intensity of 21 (prevalence 9%). There were no significant differences between the parasitism rates of male or female lizards. Polychrus acutirostris demonstrated low richness of nematode parasites, but high levels of infection with G. bahiensis. Polychrus acutirostrisis reported here as a new host for P. retusa.

Helminths of the Lizard Salvator merianae (Squamata, Teiidae) in the Caatinga, Northeastern Brazil

The lizard Salvator merianae is a widely distributed species in South America, occurring from southern Amazonia to the eastern Andes and northern Patagonia. Studies on the parasitic fauna of this lizard have revealed that it is a host for helminths in various Brazilian biomes. The present work provides new parasitological data on the gastrointestinal nematodes associated with the lizard S. merianae. Sixteen specimens were analyzed from nine different locations in a semi-arid region in northeastern Brazil. Five species of nematodes were identified. Oswaldofilaria petersi was first recorded as a parasite of the S. merianae, thus increasing the knowledge of the fauna of parasites that infect large Neotropical lizards.

Nematodes associated with Iguana iguana (Linnaeus, 1758) (Squamata, Iguanidae) in Semi-arid areas of Northeastern Brazil

Nematodes were analyzed in Iguana iguana, a large lizard Iguanidae that is widely distributed throughout the Americas. The aims of the study were investigate the helminths associated with the lizard, I. iguana in semi-arid areas of northeastern Brazil and analyze the parasitological indices (prevalence, and mean intensity of infection). A total of 18 specimens of I. iguana were examined (8 males and 10 females). The overall prevalence of infection was 66.6% (12/18), while in males, it was 75% (6/8) and in females, 60% (6/10). Iguana iguana was identified as a new host for Physaloptera sp., Atractis sp., Piratuba sp. and Subulura sp. This registered contributes to the knowledge of helminth diversity associated with this host.

Helminth parasites of Mabuya arajara Rebouças-Spieker, 1981 (Lacertilia: Mabuyidae) from Chapada do Araripe, northeastern Brazil

We provide data on the helminth fauna from the digestive tract of the lizard Mabuya arajara Rebouças-Spieker, 1981 from Chapada do Araripe, northeastern Brazil. Seventy one of the 127 lizards examined (56%) were infected with four nematode species: Physalopteroides venancioi and Physaloptera sp. (Physalopteridae), Strongyluris oscari (Heterakidae), and Parapharyngodon alvarengai (Pharyngodonidae), the latter being the component species (prevalence 53.5%; mean intensity of infection 3.37u2009±u20092.0; discrepancy index Du2009=u20090.69). The helminth P. alvarengai infected M. arajara throughout the year and showed increased infection rates in July, at the beginning of the dry season. In addition to the relationship with seasonality, lizards with greater body length and/or body mass were more infected. Relationships between number of parasites and body mass and with the sexes of lizards, on the other hand, were not found. Mabuya arajara represents a new host for these nematodes. This study contributes to the knowledge of the helminth fauna associated with the digestive tract of lizards from South America and the Caatinga domain.

Structural aspects and physiological implications of the hemoglobin of green iguana (Iguana iguana)

Abstract Iguana iguana is a lizard found in South America, and its metabolism is directly related to ambient heat. However, the physiology underlying the effect of temperature change on the metabolism of these reptiles has not been fully elucidated. I. iguana hemoglobin (iHb) was isolated and purified by exclusion chromatography. Mass spectrometry, circular dichroism, SAXS and spectroscopic characterization were used to evaluate the primary and secondary structures and oligomeric state of iHb. The secondary structure of intact iHb, which mainly consisted of α-helices, was not stable if heated at 60u202f°C. Autoxidation rates of iHb were measured at 30 and 40u202f°C, revealing a suggestive bi-exponential behavior. Furthermore, by lowering the pH from 7.4 to 6.0, an increase in autoxidation rate was observed, indicating a behavior responsive to metabolic changes. Compared to ATP, ADP showed an allosteric effect on iHb oxygenation by lowering its oxygen binding. Alignment of the amino acid sequences revealed that iHb exhibits conserved substitution of a residue at the allosteric site, suggesting that some unknown molecular mechanism accounts for the allosteric effect caused by ADP. The ability of iHB to oxygenate is directly related to metabolic changes, ensuring the survival of Iguana iguana in different environments.

Raillietiella mottae (Pentastomida: Raillietiellidae) parasitizing four species of Gekkota lizards (Gekkonidae and Phyllodactylidae) in the Brazilian Caatinga

Summary We tested the role of sex, size, and mass of the lizards Phyllopezus pollicaris, Gymnodactylus geckoides, Hemidactylus agrius, Lygodactylus klugei, and Hemidactylus brasilianus on the rates of pentastomid infection in the Brazilian Caatinga. We collected 355 individuals of these five species, of which four (prevalence of infection: P. pollicaris 15.9 %, G. geckoides 1.4 %, H. agrius 28.57 %, and H. brasilianus 4.16 %) were infected by Raillietiella mottae. Parasite abundance was influenced by host body size and mass only in P. pollicaris. Host sex did not influence the abundance of parasites in any species. Hemidactylus agrius, G. geckoides, and H. brasilianus are three new host records for pentastomids.

Helminths infecting Dryadosaura nordestina (Squamata: Gymnophthalmidae) from Atlantic Forest, northeastern Brazil

Abstract We analyzed the patterns of infection by helminths in populations of the Gymnophthalmidae lizard Dryadosaura nordestina from three Atlantic Forest fragments in Northeast Brazil. Prevalence and mean intensity of infection by location showed the following results: ARIE Mata de Goiamunduba (60.8 % and 10.4 ± 8), RPPN Engenho Gargaú (83.3 % and 20.8 ± 19.7) and Benjamim Maranhão Botanical Garden (70.4 % and 7.78 ± 5.8). We provide the first records of helminth infection for the lizard D. nordestina, in which three species of nematodes, Aplectana sp., Cosmocerca sp. and Physaloptera lutzi and one trematode Haplometroides odhneri were recovered. Trematodes of the genus Haplometroides were previously known as parasites only in snake and amphisbaenian hosts in South America. Now, our study provides the first record of a species belonging to this genus parasitizing lizards. In conclusion, our study shows that D. nordestina have a depleted helminth fauna (three species at maximum), similar to other studies with lizards of this family in Brazil and that its parasite abundance is related to host snout-vent length, but not to the sex.

Raillietiella mottae (Pentastomida: Raillietiellidae) infecting Ameiva ameiva (Squamata: Teiidae) in Araripe Plateau, Northeast Brazil

We investigated the infection by pulmonary parasites in the lizard Ameiva ameiva (Teiidae) inhabiting the Environmental Protection Area of Araripe (APA-Araripe). A total of 45 specimens were collected in three areas between the cities of Várzea Alegre and Barbalha. A Pentastomid species (Raillietiella mottae) was parasitizing (nine specimens) a male of A. ameiva with a prevalence of 2.22% considering all lizards collected in the region and prevalence of 50% considering only rainforest environment. The Pentastomids infection rates shown in this study are similar to data found for infections of other insectivorous lizards. Raillietiella mottae is considered a generalist parasite, which uses insects as intermediate hosts. The results of this study represent the first record of a Pentastomid infecting this species of lizard in South America.