Mandibular gland proteomics of the Mexican alligator lizard, Abronia graminea, and the red-lipped arboreal alligator lizard, Abronia lythrochila.

A useful approach to deepen our knowledge about the origin and evolution of venom systems in Reptilia has been exploring the vast biodiversity of this clade of vertebrates in search of orally produced proteins with toxic actions, as well as their corresponding delivery systems. The occurrence of toxins in anguimorph lizards has been demonstrated experimentally or inferred from reports of the toxic effects of the oral secretions of taxa within the Varanidae and Helodermatidae families. In the present study, we have focused on two alligator lizards of the Anguidae family, the Mexican alligator lizard, Abronia graminea, and the red-lipped arboreal alligator lizard, A. lythrochila. In addition, the fine morphology of teeth of the latter species is described. The presence of a conserved set of proteins, including B-type natriuretic peptides, cysteine-rich secretory proteins, group III phospholipase A2, and kallikrein, in submandibular gland extracts was demonstrated for both Abronia species. These proteins belong to toxin families found in oral gland secretions of venomous reptile species. This finding, along with previous demonstration of toxin-producing taxa in both paleo- and neoanguimorpha clades, provides further support for the existence of a handful of conserved toxin families in oral secretions across the 100+ million years of Anguimorpha cladogenesis.

A mystery revealed: an update on eosinophil and other blood cell morphology of the Argentine black and white tegu (Salvator merianae).

Reptile white blood cell (WBC) morphological features are strikingly variable across species. In the Argentine black and white tegu (Salvator merianae), red tegu (Salvator rufescens), and Savannah monitor (Varanus exanthematicus), previous reports described a WBC type with a single distinct, clear, linear- to ovoid- to crescent-shaped inclusion of presumptive monocytic origin. The objective of this study was to further investigate the origin of this unique WBC type with crescent-shaped inclusions. Blood samples from two Argentine black and white tegus, tegu 1, a 4-year-old female, and tegu 2, a 2-year-old presumed male, were submitted for routine hematological evaluation. Additional blood films were prepared and stained with these cytochemical stains: alkaline phosphatase (ALP; naphthol AS-MX phosphate substrate), alpha-naphthyl butyrate esterase, alpha-chloroacetate esterase, myeloperoxidase, Periodic acid-Schiff, and Sudan black B. Blood films from tegu 1 were also stained with a second ALP stain (5-bromo-4-chloro-3-indoxyl-phosphate and nitroblue tetrazolium substrate), Luna, luxol fast blue, and toluidine blue. The blood from tegu 1 was cytocentrifuged to isolate and fix the buffy coat in glutaraldehyde 2.5% aqueous solution for transmission electron microscopy. Six morphologically distinct WBC types were identified from tegu 1, including heterophils, basophils, monocytes, azurophils, lymphocytes, and the unique WBC type, which were identified as eosinophils with inclusions. WBC types in tegu 2 were similar; however, eosinophils lacked a discernable inclusion. Proper WBC identification will be useful in obtaining accurate hemogram data for this species.

Sperm Incubation in Biggers-Whitten-Whittingham Medium Induces Capacitation-Related Changes in the Lizard Sceloporus torquatus.

Sperm capacitation involves biochemical and physiological changes that enable sperm to fertilize the oocyte. It can be induced in vitro under controlled conditions that simulate the environment of the oviduct. While extensively studied in mammals, its approach in lizards remains absent. Understanding the mechanisms that ensure reproduction is essential for advancing the implementation of assisted reproductive technologies in this group. We aimed to perform a sperm analysis to determine if capacitation-related changes were induced after incubation with capacitating media. Fifteen males of Sceloporus torquatus were collected during the early stage of the reproductive season. The sperm were isolated from the seminal plasma and then diluted up to a volume of 150 µL using BWW medium to incubate with 5% CO2 at 30 °C for a maximum duration of 3 h. A fraction was retrieved hourly for ongoing sperm assessment. The sperm analysis included assessments of its motility, viability, the capacitation status using the chlortetracycline (CTC) assay, and the acrosome integrity with the lectin binding assay to detect changes during incubation. We found that total motility was maintained up to 2 h post incubation, after which it decreased. However, sperm viability remained constant. From that moment on, we observed a transition to a deeper and less symmetrical flagellar bending in many spermatozoa. The CTC assay indicated a reduction in the percentage of sperm showing the full (F) pattern and an increase in those exhibiting the capacitated (B) and reactive (RA) patterns, accompanied by an elevation in the percentage of damaged acrosomes as revealed by the lectin binding assay. In mammals, these changes are often associated with sperm capacitation. Our observations support the notion that this process may also occur in saurian. While sperm analysis is a valuable method for assessing certain functional changes, additional approaches are required to validate this process.

Comparative skull osteology of Amphisbaena arda and Amphisbaena vermicularis (Squamata: Amphisbaenidae).

The skull anatomy of amphisbaenians directly influences their capacity to burrow and is crucial for the study of their systematics, which ultimately contributes to our comprehension of their evolution and ecology. In this study, we employed three-dimensional X-ray computed tomography to provide a detailed description and comprehensive comparison of the skull anatomy of two amphisbaenian species with similar external morphology, Amphisbaena arda and Amphisbaena vermicularis. Our findings revealed some differences between the species, especially in the sagittal crest of the parietal bone, the ascendant process, and the transverse occipital crest of the occipital complex. We also found intraspecific variation within A. vermicularis, with some specimens displaying morphology that differed from their conspecifics but not from A. arda. The observed intraspecific variation within A. vermicularis cannot be attributed to soil features because all specimens came from the same locality. Specimen size and soil type may play a role in the observed differences between A. arda and A. vermicularis, as the single A. arda specimen is the largest of our sample and soil type and texture differ between the collection sites of the two species.

Description of an intramonocytic haemoparasite, Hepatozoon lainsoni sp. nov. (Apicomplexa: Adeleorina: Hepatozoidae), infecting Ameiva ameiva lizard (Reptilia: Squamata: Teiidae) in northern Brazil.

Haemogregarine (Apicomplexa: Adeleorina) parasites are considered to be the most common and widespread haemoparasites in reptiles. The genus Hepatozoon (Apicomplexa: Adeleorina: Hepatozoidae) can be found parasitizing a broad range of species and, in reptiles, they infect mainly peripheral blood erythrocytes. The present study detected and characterized a haemogregarine isolated from the lizard species, Ameiva ameiva, collected from the municipality of Capanema, Pará state, north Brazil. Blood smears and imprints from lungs, brain, heart, kidney, liver, bone marrow and spleen were observed using light microscopy and the parasite was genetically identified by molecular analysis. Morphological, morphometric and molecular data were obtained. Parasite gamonts were found in 49.5% (55/111) of the blood smears from A. ameiva, and were characterized as oval, averaging 12.0 ± 0.8 × 5.9 ± 0.6 µm2 in size, which displaced the nuclei of parasitized monocytes laterally. Parasite forms resembling immature gamonts were observed in the spleen and bone marrow of the lizards. Furthermore, phylogenetic analyses of 18S rRNA sequences did not reveal gene similarity with other Hepatozoon spp. sequences from reptiles. Thus, morphological and molecular analyses have identified a new species of Hepatozoon parasite, Hepatozoon lainsoni sp. nov., which infects monocytes of the A. ameiva lizard.

The male reproductive cycle of the brown basilisk Basiliscus vittatus (Squamata: Corytophanidae) from Tabasco, Southern Mexico.

We used histological and morphometric methods to study the testis and associated glands, including the epididymis, ductus deferens, and renal sexual segment (RSS), of specimens of Basiliscus vittatus sampled from Tabasco, Mexico (17.5926° N, 92.5816° W). Samples were collected throughout 1 year, which included the dry (February to May) and rainy (June to January) seasons. Spermatogenesis in B. vittatus is active throughout the year, but a significant increase in the testicular volume, diameters of seminiferous tubules, height of the germinal epithelium, spermiogenesis, and released spermatozoa occur in the dry season. During the rainy season, all aforementioned parameters decreased except the secretory activity of the epididymis and the RSS, which increased concomitant with an increase of the spermatozoa population within the ductus deferens. These data strongly suggest that B. vittatus reproduce year-round, but males exhibit a peak in spermatogenic activity during the dry season and a peak in insemination and/or copulation at the beginning of the rainy season. We highlight the importance of analyzing not only the testis but also accessory ducts and glands when determining the reproductive cycles of reptiles. The reproductive cycle of B. vittatus is discussed in relation to the environmental conditions of Southern Mexico and is compared to that of other squamates.

A NEW SPECIES OF CHIGGER MITE AND THE RECORD OF A GASTROINTESTINAL NEMATODE IN SCELOPORUS CAUTUS (SQUAMATA: PHRYNOSOMATIDAE) FROM THE CHIHUAHUAN DESERT PROVINCE IN COAHUILA, MEXICO.

The chigger species Acomatacarus coahuilensis n. sp. (Acariformes: Trombidiformes: Leeuwenhoekiidae) inhabiting the neck scales of the wary spiny lizard Sceloporus cautus Smith, 1938 (Squamata: Iguania: Phrynosomatidae), from Chihuahuan Desert Province, Coahuila, Mexico, is described herein. The new mite species is assigned to the genus AcomatacarusEwing, 1942, based on a palptarsus with 6 branched setae plus the tarsala (ω). This new species can be separated from the other species in this genus mainly based on the combination of the following characters: presence of mastisetae (MTa) on tarsus III and tibiala (φ) on tibia III, subterminala (ζ1), parasubterminala (z), and pretarsala (ζ2) on tarsus I, 2 genualae (σ1-2) on genu I, onychotriches and claw-like empodium of legs I-III, and absence of mastisetae on tibia III. In addition to the new species, the gastrointestinal nematode Skrjabinoptera phrynosoma (Ortlepp, 1922) Schulz, 1927 (Physalopteridae), was also found, which represents a new host record in the wary spiny lizard. This study reports the third species of the genus Acomatacarus recorded from Mexico and the first record of chigger mites and helminth parasites associated with Sc. cautus.

Immunolocalization of activin and inhibin at different stages of follicular development in the lizard Sceloporus torquatus.

The activins and inhibins are glycoproteins with a role in the follicular development of vertebrates, that are found in follicular fluid and somatic follicular cells, with a different pattern among taxa. The principal function of activin (Act) is to modulate the follicle-stimulating hormone (FSH) synthesis and secretion, whereas inhibin (Inh) downregulates it. Both factors are modulators of intraovarian follicular recruitment, oocyte maturation, cell proliferation, and steroidogenic activity. Our aim was to characterize the immunolocalization of Act and Inh in the ovarian follicles during the reproductive cycle of the lizard Sceloporus torquatus. Act was detected in the granulosa cells and oocyte cortex in the different stages of follicular development. On the other hand, we identified Inh in the oocyte cortex and the cytoplasm of pyriform and small cells of previtellogenic follicles. Also, we found immunoreactivity in the oocyte cortex, theca, and small cells of vitellogenic and preovulatory follicles. Our data provide evidence that Act and Inh have changes related to the stage of follicular development. This dynamic appears to be conserved among vertebrates and is fundamental to ensure an adequate follicular development in this specie.

RECORD OF Hemidactylus agrius (GEKKONIDAE) IN THE DIET OF Thamnodynastes phoenix (DIPSADIDAE) IN NORTHEASTERN BRAZIL / Registro de Hemidactylus agrius (Gekkonidae) en la dieta de Thamnodynastes phoenix (Dipsadidae) en el noreste de Brasil

ABSTRACT Information on snake diet is scarce, being obtained from specimens deposited in scientific collections or through occasional records. Thamnodynastes species have a generalist diet, although predominantly batracophagus. Thamnodynastes phoenix is an endemic snake in Brazil, which was described recently, and little is known about its ecology. Herein, we report the first record of Hemidactylus agrius in the diet of T. phoenix in northeastern Brazil. Although there is a record of another lizard in its diet, this is the first record of a Gekkonidae as prey for this species. Studies on snake diet provide important information about natural history, contributing to the evolutionary biology and conservation of the species, which are still limited.

RESUMEN La información sobre la dieta de las serpientes es escasa, ya que se obtiene a partir de especímenes depositados en colecciones científicas o mediante registros ocasionales. Las especies de Thamnodynastes tienen una dieta generalista, aunque predominantemente batracophagus. Thamnodynastes phoenix es una serpiente endémica de Brasil, que fue descrita recientemente y se sabe poco sobre su ecología. Aquí, reportamos el primer registro de Hemidactylus agrius en la dieta de T. phoenix en el noreste de Brasil. Aunque hay un registro de otro lagarto en su dieta, este es el primer registro de un Gekkonidae como presa de la especie. Los estudios sobre la dieta de las serpientes brindan información importante sobre la historia natural, lo que contribuye a la biología evolutiva y la conservación de la especie, que aún son limitadas.

Drought correlates with reduced infection complexity and possibly prevalence in a decades-long study of the lizard malaria parasite Plasmodium mexicanum.

Microparasites often exist as a collection of genetic 'clones' within a single host (termed multi-clonal, or complex, infections). Malaria parasites are no exception, with complex infections playing key roles in parasite ecology. Even so, we know little about what factors govern the distribution and abundance of complex infections in natural settings. Utilizing a natural dataset that spans more than 20 years, we examined the effects of drought conditions on infection complexity and prevalence in the lizard malaria parasite Plasmodium mexicanum and its vertebrate host, the western fence lizard, Sceloporus occidentalis. We analyzed data for 14,011 lizards sampled from ten sites over 34 years with an average infection rate of 16.2%. Infection complexity was assessed for 546 infected lizards sampled during the most recent 20 years. Our data illustrate significant, negative effects of drought-like conditions on infection complexity, with infection complexity expected to increase by a factor of 2.27 from the lowest to highest rainfall years. The relationship between rainfall and parasite prevalence is somewhat more ambiguous; when prevalence is modeled over the full range in years, a 50% increase in prevalence is predicted between the lowest and highest rainfall years, but this trend is not apparent or is reversed when data are analyzed over a shorter timeframe. To our knowledge, this is the first reported evidence for drought affecting the abundance of multi-clonal infections in malaria parasites. It is not yet clear what mechanism might connect drought with infection complexity, but the correlation we observed suggests that additional research on how drought influences parasite features like infection complexity, transmission rates and within-host competition may be worthwhile.

Macro- and microscopic brain anatomy of the amazon lava lizard (Tropidurus torquatus) (WIED, 1820) / Anatomia macro- e microscópica do encéfalo do calango (Tropidurus torquatus) (WIED, 1820)

Reptiles have a key role in understanding amniotes' reproductive independence of water. Many adaptations arose, including in locomotor patterns and behaviours, and the nervous system adapted to those new habits.We have described the macroscopic anatomy and cytoarchitecture of the Amazon Lava Lizard brain (Tropidurus torquatus), an abundant lizard in South America. Fifteen specimens were captured, euthanized and their brains were dissected, eight of these were processed and stained in haematoxylineosin. Their main areas of the brain are the telencephalon and diencephalon, in the forebrain, tectum and tegmentum, in the midbrain and bulbota and cerebellum, in the hindbrain. The main and accessory olfactory bulbs are the most rostral structure of the brain and are composed of six layers. Brain hemispheres compose the telencephalon and are divided in pallium and subpallium. Medial, dorsomedial, lateral and dorsal cortices are part of the pallium. Striatum, pallidum and septum compose the subpallium. The diencephalon is composed of thalamus, epithalamus and hypothalamus. The midbrain has a ventral tegmentum, composed of torus semicircularis and a dorsal 14 layered optic tectum. Most part of the hindbrain is composed of the bulbo, and the cerebellum arises from it, forming a three-layered plate like structure. In general, the brain of Tropidurus torquatusresembles those of other lizards, with its own adaptations

Os répteis têm um papel fundamental para a compreensão da independência reprodutiva da água que surgiu nos amniotas. Várias adaptações ocorreram, inclusive em padrões e comportamentos locomotores, e o sistema nervoso se adaptou a esses novos hábitos. Descrevemos a anatomia macroscópica e a citoarquitetura do encéfalo do calango (Tropidurus torquatus), um lagarto abundante na América do Sul. Quinze espécimes foram capturados, eutanasiados e seus encéfalos dissecados, oito destes foram processados e corados em hematoxilina-eosina. As principais áreas do cérebro são o telencéfalo e o diencéfalo, na parte anterior do encéfalo, teto e tegmento, no mesencéfalo e bulbo e cerebelo, na parte posterior do encéfalo. Os bulbos olfatórios principais e acessórios são as estruturas mais rostrais do cérebro e são compostos por seis camadas. Os hemisférios cerebrais compõem o telencéfalo e são divididos em pálio e subpálio. Os córtices medial, dorsomedial, lateral e dorsal fazem parte do pálio. Estriado, pálido e septo compõem o subpálio. O diencéfalo é composto pelo tálamo, epitálamo e hipotálamo. O mesencéfalo possui um tegmento ventral, composto de torus semicircularis e um tecto óptico dorsal com 14 camadas. A maior parte da parte posterior do encéfalo é composta pelo bulbo, e o cerebelo surge como uma projeção dessa estrutura, em formato plano, com três camadas. Em geral, o encéfalo de Tropidurus torquatusse assemelha ao de outros lagartos, com suas próprias adaptações.

Ciclo reprodutivo do lagarto teiú, Salvator merianae (Squamata, Teiidae)

Salvator merianae é um lagarto teiú ovíparo, de grande porte, diurno, forrageador ativo e terrestre. Possui a maior distribuição geográfica do gênero, com ocorrência em todos os biomas brasileiros. Os teiús são vistos expostos ao sol durante o verão e no inverno permanecem entocados e inativos por longos períodos. Apesar de S. merianae ser uma espécie bastante conhecida e de ampla distribuição, sua biologia reprodutiva é pouco explorada. Desta maneira, foi descrito o ciclo e outros aspectos da biologia reprodutiva de machos e fêmeas da espécie através de análises morfológicas e histológicas de 86 espécimes brasileiros. Foram avaliados tecidos coletados de vagina, ovários, útero e infundíbulo de 26 fêmeas, assim como testículos, epidídimo, ducto deferente e rim de 60 machos dos espécimes salvaguardados em coleções biológicas científicas. As amostras foram processadas para análises histológicas por Hematoxilina/Eosina (H/E) e observadas sob microscopia de luz. O comprimento rostro-cloacal (CRC) dos animais variou de 85,44 mm a 420 mm nos machos e de 89,12 mm a 360 mm nas fêmeas. Nos machos imaturos, o testículo foi caracterizado por túbulos seminíferos em formação e sem lúmen. O menor macho ativo reprodutivamente foi coletado na primavera e apresentou o CRC de 250 mm. Este espécime estava no início da espermatogênese e o segmento sexual renal (SSR) não estava hipertrofiado, pois ainda não havia recebido a indução hormonal da testosterona produzida pelo testículo. Os demais exemplares machos adultos coletados na primavera apresentaram testículo em pico de espermatogênese, com observações de espermatozoides no epidídimo e SSR hipertrofiado. Nas fêmeas, a maioria se encontrava em vitelogênese primária (v1). Apenas um espécime (MNRJ27516) estava em vitelogênese secundária (v2) e um espécime com ovos (MNRJ27506), ambos coletados na primavera. Foi observado também receptáculos de estocagem no infundíbulo posterior, porém, sem presença de espermatozoides. Os teiús apresentam um ciclo reprodutivo sazonal com um estágio de desenvolvimento folicular ativo e espermatogênese no início da primavera, época do ano em que ocorre a cópula.

Preferência alimentar em lagartos teiús , pertencentes a espécie Salvator merianae (Duméri l & Bibron, 1839)

The suborder Sauria, corresponds to the group with the highest diversity of species within the Squamata, totaling 7310 currently living species. For Brazil are found 387 species divided into 86 genus. The tegulizard, targed of this work , belongs to the Teiidae famil y and the Salvator merianae species , but there are other animals popularly called tegus belonging to the genus Tupinambis . The tegulizard is the representative of the largest lizard found in Brazil, reaching up to 500mm in Snout- vent length (SVL). S. merianae has an elongated body, a pointed snout and a whip- shaped tail, similar characteristics to those of the Teiidae family. The objective of this work is to observe and clarify whether the target species has a food preference. According to the literature, this species has omnivorous, generalist, opportunistic and seed - dispersing eating habits, but little is said about having a preference for certain types of food to the point of making choices. For the experiment, seven adult animals, were used, males and in full health, were offered several pairs of food separated in feeders, in the amount of 50g for each type of food and observed which animals invested, fed and if all was ingested, within 20 minutes. The foods offered were animal protein (mouse, beef or chicken), fruits, eggs and industrialized feed. The results previously showed that the lizards studied, showed a food preference, sometimes invested in a feeder due to the smell of the food, but did not consume it, later they went to the second feeder and ingested the food, this found that there was a choic e of food item.

A subordem Sauria , corresponde ao grupo com maior diversidade de espécies dentro dos Squamata, totalizando 7310 espécies viventes atualmente. Para o Brasil são encontradas 387 espécies dividid as em 86 gêneros. O lagarto teiú, alvo deste trabalho pertence a família Teiidae e a espécie Salvator merianae, mas existem outros animais popularmente chamados de teiús que pertencem ao gênero Tupinambis. O lagarto teiú é o representante do maior lagarto encontrado no Brasil, podendo atingir até 500mm de comprimento rostro - cloacal (CRC). O S. merianae apresenta corpo alongado, focinho pontiagudo e cauda em forma de chicote, características semelhantes dos representantes da família Teiidae. O trabalho tem como objetivo observar e esclarecer se a espécie alvo apresenta preferência alimentar. De acordo com a literatura esta espécie apresenta hábito alimentar onívoro, generalista, oportunista e dispersor de semente, contudo pouco se fala sobre apresentar preferência por determinados tipos de alimentos a ponto de realizarem escolhas . Para o experimento foram utilizado s sete animais adultos, machos e em plena saúde, onde foram ofertadas combinações em duplas de alimentos separados em comedouros, na quantia de 50g para cada tipo de item alimentar e observado em qual os animais investiam, se alimentavam , e se era ingerido todo o alimento, no período de 20 minutos. Os alimentos ofertados foram proteína animal (camundongo, carne bovina ou frango), frutas, ovos e ração industrializada. Os resultados mostraram previamente que os lagartos alvo d o estudo demonstraram preferência alimentar, por vezes investiram em um comedouro devido ao cheiro do alimento, mas não chegaram a consumir: posteriormente foram até ao segundo comedouro fazendo a ingestão do alimento. Isso constatou que houve escolha preferencial do item alimentar.

Visual Signaling in the Semi-Fossorial Lizard Pholidobolus montium (Gymnophthalmidae).

It has been suggested that gymnophthalmids, like most semi-fossorial lacertoids, rely more in chemical cues to communicate, in comparison to other groups, like Iguanids, on which communication is mostly based on visual signaling. We present the first description of visual signaling in the Andean lizard Pholidobolusmontium (Gymnophthalmidae) and a complete ethogram based on ex situ observations (34 different types of behaviors including positions and simple movements). Through the design of conspecific stimulus experiments, we were able to recognize leg-waving as a visual signal, as it is only displayed in presence of conspecifics or in presence of a mirror and was one of first and most frequent displays in this context. We also detected other visual displays like neck-arching and tail-undulation which may also be relevant as visual signals. Based on our results, we propose that visual signaling is also possible in semi-fossorial lizards; however, further studies regarding chemical signal recognition and color detection are required to confirm our hypothesis.

Ampliación de la distribución geográfica y estado de conservación de Ctenoblepharys adspersa (Tschudi, 1845)

Ampliamos la distribución geográfica de Ctenoblepharys adspersa (Liolaemidae), una especie de saurio endémico y amenazado del desierto peruano. Nuestro nuevo registro extiende la distribucion de esta especie en 60 km (línea recta) de la localidad más oriental previamente conocida, la Reserva Nacional de Paracas. Registramos dos tipos de hábitat nuevos para C. adspersa al interior de las estribaciones andinas e identificamos las plantas nativas asociadas a sus hábitats. Además, revisamos el estado de conservación de esta especie y los desafíos que implican su conservación, resaltando que la mayoría de las poblaciones son vulnerables a los impactos en su hábitat producto del desarrollo de infraestructura urbana y/o agrícola.

We extend the geographical distribution of Ctenoblepharys adspersa (Liolaemidae) an endemic and threatened lizard species from the Peruvian desert. Our new record extends the known species distribution ca. 60 km (straight line) east-southeastern from the eastemost record at Paracas National Reserve. We recorded two new type of habitat for C. adspersa that reach to the Pacific foothills and identified the native plants associated to its habitats. Moreover, we review the conservation status and the challenges that facing it, highlighted that most of its populations are vulnerable to the impacts on their habitat caused by the development of urban and agricultural infrastructure.

Co-occurrence of Eutrombicula alfreddugesi and Oswaldofilaria chabaudi in Tropidurus torquatus and first report of microfilariae in the chigger mite: possible evidence of a lifecycle pathway?

While much attention has been paid to vector-borne filariasis, diseases that threaten millions of people in tropical and subtropical countries, the literature on host-parasite associations and transmission strategies of filarial nematodes in wildlife is scarce. Here, we report the co-occurrence of chigger mites (Eutrombicula alfreddugesi) and onchocercid nematodes (Oswaldofilaria chabaudi) parasitizing the lizard Tropidurus torquatus in the State of Minas Gerais, Brazil. Examination of chiggers established, for the first time, the occurrence of microfilariae in trombiculid mites (Trombiculidae). These larvae were morphologically similar to those recovered from adult females of O. chabaudi. The current evidence suggests that chiggers do not play a role in the transmission of filarioid nematodes, but rather act as accidental or dead-end hosts. Nevertheless, considering the polyphagous nature of trombiculid mites, similar to blood-sucking insects involved in the transmission of several infectious diseases, further studies may shed light on the potential role of chiggers as vectors of filarioids.

Historical and fossil evidence of an extinct endemic species of Leiocephalus (Squamata: Leiocephalidae) from the Guadeloupe Islands.

Documenting recent extinction events against the backdrop of increasing human-induced environmental pressure is complicated by the lack of historical and subfossil evidence for most parts of the world. This paucity of data renders it particularly difficult to evaluate the human impact on fragile environments, such as small islands, that may have been heavily altered by historical human exploitation. Here we describe a new species of an extinct Leiocephalus lizard from Guadeloupe, Leiocephalus roquetus sp. nov. based on recent discoveries of both a previously undocumented historically taxidermy specimen and of a large assemblage of subfossil bone remains from La Désirade Island. This new species presents a primitive morphology compared to all extant species of its genus and provides evidence for the past existence of a Lesser Antillean clade of Leiocephalus lizards that was completely wiped out in the centuries following the European colonization of these islands. Our study demonstrates how paleontological approaches can help to better understand the history of human environmental impact as well as the degree of degradation of modern ecosystems.

Platinossomose em felino doméstico no município de Pelotas, RS, Brasil / Platinosomosis in feline domestic in the municipality of Pelotas, RS, Brazil / Platinosomosis en felinos domésticos en el municipio de Pelotas, RS, Brasil

Platynosomum spp. é um trematódeo, da família Dicrocoeliidae, que tem como hospedeiros definitivos, os felídeos, mas também pode parasitar primatas e aves silvestres. Animais que possuem o hábito de se alimentar de répteis ou anfíbios, são mais susceptíveis. Acomete principalmente o fígado e os ductos biliares, mas pode ser eventualmente encontrado também no intestino delgado, ductos pancreáticos, pulmões e outros tecidos. A fisiopatologia inclui quadro de colangite crônica, podendo se estender e acometer o parênquima hepático e culminar com colangiohepatite, fibrose biliar, cirrose e obstrução biliar. Os sinais clínicos variam conforme a gravidade do caso e duração da infecção. As manifestações clínicas incluem anorexia, letargia, perda de peso, hepatomegalia, distensão abdominal e vômitos, podendo ocorrer, ainda, icterícia e alteração de consistência das fezes. Os gatos adultos, não domiciliados ou domiciliados com acesso à rua que possuem hábitos de caça, são mais predispostos. O diagnóstico definitivo pode ser feito pela pesquisa parasitológica e presença de ovos em análise coproparasitológica, pela identificação de ovos na bile e mais frequentemente por histopatologia hepática. O tratamento consiste no uso de anti-helmínticos, sendo que o mais eficaz é o praziquantel. Além disso, medidas preventivas devem ser adotadas, como evitar que os gatos tenham acesso aos hospedeiros intermediários. O presente relato, consiste no diagnóstico coproparasitológico de platinossomose em dois felinos domésticos, no município de Pelotas, RS, Brasil.(AU)

Platynosomumspp. is a trematode, from the family Dicrocoeliidae, which has felids as its definitive host, but can also parasite primates and wild birds. Animals that have a habit of feeding on reptiles or amphibians are more susceptible. It mainly affects the liver and bile ducts, but it can eventually be found also in the small intestine, pancreatic ducts, lungs and other tissues. Pathophysiology includes chronic cholangitis, which may extend and affect the liver parenchyma and culminate in cholangiohepatitis, biliary fibrosis, cirrhosis and biliary obstruction. Clinical signs vary according to the severity of the case and the duration of the infection. Clinical manifestations include anorexia, lethargy, weight loss, hepatomegaly, bloating and vomiting, and jaundice and alteration of stool consistency may also occur. Adult cats, homeless or homeless with access to the street who have hunting habits, are more predisposed. The definitive diagnosis can be made through parasitological research and presence of eggs in coproparasitological analysis, by identifying eggs in the bile and more often through hepatic histopathology. Treatment consists of the use of anthelmintics, the most effective of which is praziquantel. In addition, preventive measures must be adopted, such as preventing cats from having access to intermediate hosts. The present report consists of the coproparasitological diagnosis of platinosomosis in two domestic cats, in the municipality of Pelotas, RS, Brazil.(AU)

Platynosomum spp. es un trematodo, de la familia Dicrocoeliidae, que tiene a los felinos como hospedadores definitivos, pero también puede parasitar primates y aves silvestres. Los animales que tienen la costumbre de alimentarse de reptiles o anfibios, sonmás susceptibles. Afecta principalmente al hígado y los conductos biliares, pero eventualmente también se puede encontrar en el intestino delgado, los conductos pancreáticos, los pulmones y otros tejidos. La fisiopatología incluye la colangitis crónica, que puede extenderse y afectar el parénquima hepático y culminar en colangiohepatitis, fibrosis biliar, cirrosis y obstrucción biliar. Los signos clínicos varían según la gravedad del caso y la duración de la infección. Las manifestaciones clínicas incluyen anorexia, letargo, pérdida de peso, hepatomegalia, distensión abdominal y vómitos, e ictericia y alteración de la consistencia de las heces. Los gatos adultos, sin hogar o sin hogar con acceso a la calle que tienen hábitos de caza, están más predispuestos. El diagnóstico definitivo se puede realizar mediante la investigación parasitológica y la presencia de huevos en el análisis coproparasitológico, mediante la identificación de los huevos en la bilis y más a menudo mediante la histopatología hepática. El tratamiento consiste en el uso de antihelmínticos, el más eficaz de los cuales es el praziquantel. Además, se deben adoptar medidas preventivas, como evitar que los gatos tengan acceso a huéspedes intermediarios. El presente informe consiste en el diagnóstico coproparasitológico de platinosomosa en dos gatos domésticos, en el municipio de Pelotas, RS, Brasil.(AU)

Health status of Polychrus gutturosus based on physical examination, hematology and biochemistry parameters in Costa Rica.

Studies evaluating the health status and characteristics of free-ranging wildlife populations are scarce or absent for most species. Saurian health assessments are usually performed in species that have conservation issues or that are kept in captivity. The Berthold's bush anole (Polychrus guturossus) is one of eight species belonging to the genus Polychrus, the only representative of the family Polychrotidae. Only a handful of studies have been reported concerning these lizard's morphological variation, ecology, and natural history, probably because P. gutturosus is a canopy dweller and it can be difficult to locate individuals. It is believed that deforestation and habitat modification could pose a threat for this species, although to date no health assessment has been done. The aim of this study was to generate health baseline data on P. gutturosus. Forty Berthold's bush anoles (20 males and 20 females) were sampled at the Pacific versant in Costa Rica, where physical examination, skin and cloacal temperatures, and blood samples were obtained from individuals immediately after capture. Animals from the studied population were all healthy (body condition 2.5-3.0/5.0). No lesions or ectoparasites were detected, but hemoparasites were found in nine individuals. Hematological and biochemical values were obtained, and the morphology of leukocytes were found to be similar to other iguanians. A positive correlation was found between the tissue enzymes aspartate aminotransferase (AST) and creatinine kinase (CK) and a negative correlation was found between skin and cloacal temperatures and AST and CK. There were positive correlations between female weight and total protein, calcium, and the calcium and phosphorus ratio. No significant inter-sex differences were found in biochemical values, despite females being larger than males. This is the first health assessment performed on a free-ranging canopy dwelling lizard. These findings provide baseline data that may be useful for future monitoring if the species faces changes in health status due to anthropogenic causes or natural disturbances.

Living in a cold tropical mountain do the microhabitat use and activity pattern change with elevation in the highAndean lizard Stenocercus trachycephalus (Squamata Tropiduridae)

The high mountain environment is a tough habitat that imposes many challenges to reptiles. As temperature decreases with altitude and has a dramatic variation throughout the day in the tropical mountains, ectotherms must cope with these harsh conditions. We studied the use of microhabitat and activity patterns of Stenocercus trachycephalus in the eastern Andes mountain range of Colombia. Three localities were sampled across the wide altitudinal distribution of this lizard species, in a range from 2,670 to 3,950 m a.s.l. The initial hypothesis was that these natural history traits would change with altitude but instead, we found that they remained roughly consistent, showing the great plasticity of this species. The results support that this lizard is a microhabitat-generalist using principally herb across the gradient, rarely shifting to specific plants or microhabitats such as rocks depending on availability. Regarding the activity pattern, this species was active throughout the day from 8:00 to 16:00 with a similar pattern along the gradient. Nevertheless, some differences were detected across localities. The activity pattern shifted from bimodal in the lower locality to unimodal in the higher ones. As expected, a correlation between temperature and activity patterns was found in one of the study sites. However, this was not the case for the lower and mid-elevation localities, where there was no correlation between these variables. The mid-elevation study site was the most interesting locality as the use of microhabitat relied virtually just on the herb stratum and the activity was constrained to the morning hours. These findings may be the result of the synergic effects of other ecological variables (weather variability, human impact, predation, population structure, or reproductive season). Our study gives the basis for a better understanding of how behavior (microhabitat choice and hours of activity) of ectotherms can help to counter thermal constraints in the neotropics when facing an altitudinal gradient. Further studies should focus on the thermal biology of this species, considering the influence of anthropic impact on these lizards populations.(AU)