First molecular detection and genetic diversity of Hepatozoon sp. (Apicomplexa) and Brugia sp. (Nematoda) in a crocodile monitor in Nakhon Pathom, Thailand.

The crocodile monitor (Varanus salvator) is the most common monitor lizard in Thailand. Based on habitat and food, they have the potential to transmit zoonoses, with a high possibility of infecting ectoparasites and endoparasites. Diseases that could infect crocodile monitors and be transmitted to other animals, including humans. This research aims to identify and evaluate the phylogenetic relationships of Hepatozoon sp. and sheathed microfilaria in crocodile monitors. The phylogenetic analyses of Hepatozoon, based on 18S rRNA, and sheathed microfilaria, based on the COX1 gene, revealed that the Hepatozoon sp. were grouped with H. caimani, while sheathed microfilaria were grouped together with B. timori. This study provides insights into the genetic diversity and host-parasite interactions of hemoparasites in crocodile monitors in Thailand.

Hemolivia species infecting Central American wood turtles (Rhinoclemmys pulcherrima manni) and problems with differential diagnosis within the genus Hemolivia.

Blood parasites of the genus Hemolivia Petit, Landau, Baccam and Lainson, 1990 (Adeleorina: Karyolysidae) are hemogregarines of ectothermic vertebrates, such as lizards, chelonians, and toads. Only five species of Hemolivia from vertebrate hosts and one from their tick vector have been described so far. In the present study, Central American wood turtles (Rhinoclemmys pulcherrima manni) originating from Southern Nicaragua were screened for the presence of hemogregarines. Ten out of 30 specimens (33.3%) were positive for Hemolivia using both approaches - microscopy and PCR-based analyses. Phylogenetic analyses based on the 18S rRNA gene revealed the presence of two haplotypes, both placed as sister taxa in the Hemolivia clade. Their phylogenetic position was supported by high bootstrap values and high posterior probabilities, suggesting that there are at least two new distinct haplotypes corresponding to two distinct species. However, the specimens of each haplotype were microscopically indistinguishable from each other based on the gamont morphology, therefore, only a single species could be described and named, as Hemolivia pulcherrima n. sp. We consider that the uniform morphology of the most common blood stages of species of the genus Hemolivia complicates their differential diagnosis. Sequence divergence and different host spectra, therefore, remain the only differentiating tools.

Title: Espèces d'Hemolivia infectant les tortues peintes d'Amérique centrale (Rhinoclemmys pulcherrima manni) et problèmes de diagnostic différentiel au sein du genre Hemolivia. Abstract: Les parasites sanguins du genre Hemolivia Petit, Landau, Baccam et Lainson, 1990 (Adeleorina : Karyolysidae) sont des hémogrégarines de vertébrés ectothermes, tels que les lézards, les tortues et les crapauds. Seules cinq espèces d'Hemolivia provenant d'hôtes vertébrés et une de leur tique vectrice ont été décrites jusqu'à présent. Dans cette étude, des tortues peintes d'Amérique centrale (Rhinoclemmys pulcherrima manni) originaires du sud du Nicaragua ont été examinées pour détecter la présence d'hémogrégarines. Dix tortues sur 30 (33,3 %) étaient positives pour Hemolivia en utilisant les deux approches de microscopie et d'analyse de PCR. Les analyses phylogénétiques basées sur le gène de l'ARNr 18S ont révélé la présence de deux haplotypes, tous deux placés comme taxons frères dans le clade Hemolivia. Leur position phylogénétique était étayée par des valeurs de bootstrap et des probabilités postérieures élevées, suggérant qu'il existe au moins deux nouveaux haplotypes distincts correspondant à deux espèces distinctes. Cependant, les spécimens de chaque haplotype étaient impossibles à distinguer les uns des autres au microscope sur la base de la morphologie des gamontes. Par conséquent, une seule espèce a pu être décrite et nommée, comme Hemolivia pulcherrima n. sp. Nous considérons que l'uniformité de la morphologie des stades sanguins les plus courants des espèces du genre Hemolivia complique leur diagnostic différentiel. Les divergences de séquences et les différents spectres d'hôtes restent donc les seuls outils de différenciation.

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.

Differential recovery ability from infections by two blood parasite genera in males of a Mediterranean lacertid lizard after an experimental translocation.

Different blood parasites can co-infect natural populations of lizards. However, our knowledge of the host's ability to recover from them (i.e., significantly reduce parasitemia levels) is scarce. This has interest from an ecological immunology perspective. Herein, we investigate the host recovery ability in males of the lizard Psammodromus algirus infected by parasite genera Schellackia and Karyolysus. The role of lizard hosts is dissimilar in the life cycle of these two parasites, and thus different immune control of the infections is expected by the vertebrate host. As Schellackia performs both sexual and asexual reproduction cycles in lizards, we expect a better immune control by its vertebrate hosts. On the contrary, Karyolysus performs sexual reproductive cycles in vectors, hence we expect lower immune control by the lizards. We carried out a reciprocal translocation experiment during the lizards' mating season to evaluate both parasitemia and leukocyte profiles in male lizards, being one of the sampling plots close to a road with moderate traffic. These circumstances provide a combination of extrinsic (environmental stress) and intrinsic factors (reproductive vs. immune trade-offs) that may influence host's recovery ability. We recaptured 33% of the lizards, with a similar proportion in control and translocated groups. Karyolysus infected 92.3% and Schellackia 38.5% of these lizards. Hosts demonstrated ability to significantly reduce parasitemia of Schellackia but not of Karyolysus. This suggests, in line with our predictions, a differential immune relationship of lizards with these parasites, at time that supports that parasites with different phylogenetic origins should be analyzed separately in investigations of their effects on hosts. Furthermore, lizards close to the road underwent a stronger upregulation of lymphocytes and monocytes when translocated far from the road, suggesting a putative greater exposure to pathogens in the latter area.

Molecular Survey and Microscopic Examination of Haemoparasites Infecting Lizards from Morocco.

PURPOSE: Understanding the factors influencing parasite diversification, their distribution and infection patterns among hosts provides valuable information on the impact of parasitism on natural populations and the dynamics and evolution of disease outbreaks. In this study, we investigated prevalence and intensity of infection by blood parasites, the diversity, distribution, host specificity and infection patterns of apicomplexan parasites in lizards of Morocco. METHODS: Samples from lizard specimens were collected between 2019 and 2021 from different prospected localities in Morocco. In total, 1500 lizards were collected, and their blood and tail tips were screened for blood parasites. RESULTS: Using a PCR approach, we detected two distinct apicomplexan parasite groups (haemogregarines and haemococcidians) and also Stramenopiles (Proteromonas). A significant difference was identified between hosts families, with no agamids or skinks infected and with particularly high infection rates in lacertids. Twenty-four samples were sequenced and included in a phylogenetic assessment. Two samples of Atlantolacerta andreanskyi were infected with unidentified species of Proteromonas. Three samples were infected with haemococcidians, including two samples with Schellackia and another sample with Lankesterella, more closely related to others isolated from bird hosts. These are the first reports of Lankesterella and Proteromonas in these lizards from Morocco. Nineteen different isolates of the complex of Hepatozoon/Karyolysus were identical or very similar to previously sequenced parasites from North Africa and Iberian Peninsula and included new host species. CONCLUSION: Our results highlight the need for future research on the vectors involved in transmission that may influence the ecology and distribution patterns of these parasites. Given that Morocco is a hot spot of endemicity and reptile richness, our results are relevant not only in the context of their taxonomy, but can also have implications for conservation.

How agricultural land use affects the abundance and prevalence of monoxenous and heteroxenous helminths in the generalist lizard Tropidurus hispidus.

Among the forms of anthropogenic disturbance, agricultural land use is one of the main threats to biodiversity. Understanding how interactions between parasites and hosts are affected by agricultural land use allows predictions of how these anthropogenic impacts affect parasites. Although parasitism patterns are affected by agricultural land use, it is noteworthy that different groups of parasites can respond differently to these environmental alterations. While heteroxenous species need more than one host to complete their life cycle and tend to be more harmed by anthropization, monoxenous species, which need only one host to complete their life cycle, tend to be less harmed. In this work, we evaluate how agricultural land use affects the abundance and prevalence of parasitism for monoxenous and heteroxenous helminths in the generalist lizard Tropidurus hispidus in Caatinga Domain, Brazil. We recorded differences in abundance and prevalence of heteroxeneous (higher in conserved areas) and monoxenous helminths (higher in agricultural areas). Heteroxenous helminths that have lizards as definitive hosts are mainly obtained through diet. Tropidurus hispidus predominantly consumes insects, so it is possible that the lower abundance and prevalence of heteroxenous parasites in agricultural areas, beyond habitat simplification, is related to the decrease in the insect population. As monoxenous species do not need an intermediate host, it is possible that this aspect has influenced their greater success in anthropogenic environments than heteroxenous species. This contrasting result reinforces the need for a separate assessment between these groups when evaluating effects of land use.

Molecular characterization of Schellackia parasites in an urban population of sand lizards (Lacerta agilis) from Berlin, Germany.

Lizards are hosts of several taxa of unicellular parasites of the phylum Apicomplexa, including Karyolysus, Schellackia, Lankesterella, and Hepatozoon. Parasite prevalence and the impact of infections on lizard biology remain largely unexplored. In this study, blood parasite infections were investigated in sand lizards (Lacerta agilis) from Berlin, Germany. Eighty-three individuals were investigated, and the detected blood parasites were identified as Schellackia sp. The combination of microscopic and molecular screening revealed a prevalence of 14.5%. Parasitemia values were low and most infections were subpatent. Phylogenetic analysis recovered a close relationship of the Schellackia parasites of this study with Schellackia sp. parasites of different Lacerta and Podarcis lizard species from Spain. Monitoring of Schellackia parasite infections in free-ranging lizards contributes to a better understanding of the distribution, diversity, and phylogenetic relationships of the neglected parasite taxon.

Redescription of Thubunaea schukurovi Annaev, 1973 from Ablepharus chernovi, with notes on the members of Thubunaea (Spirurida: Physalopteridae) from the Palaearctic and Indomalayan realms.

The spirurid nematode Thubunaea schukurovi Annaev, 1973 (Physalopteridae) is redescribed by means of light microscopy and scanning electron microscopy from Ablepharus chernovi collected in Çamliyayla, Turkey. This is the first record of the species from this host and the first record of the genus Thubunaea from Turkey. The taxonomic status of the species of the genus Thubunaea from the Palaeacrtic and Indomalayan realms is reviewed based on their original morphological descriptions; as a result, Thubunaea dessetae Barus & Tenora, 1976, a parasite of Saara hardwickii (Gray) (Agamidae) in Afghanistan, is transferred to the genus Pseudabbreviata as Pseudabbreviata dessetae (Barus & Tenora, 1976) n. comb. Several species described in India, that is, Thubunaea singhi Deshmukh, 1969 and Thubunaea brooki Deshmukh, 1969, both from Hemidactylus brookii Gray (Gekkonidae), and Thubunaea aurangabadensis Deshmukh, 1969 and Thubunaea syedi Deshmukh, 1969, both from Hemidactylus giganteus Stoliczka, are considered members of the genus Physalopteroides; therefore, the following new combinations are proposed: Physalopteroides singhi, Physalopteroides brooki, Physalopteroides aurangabadensis and Physalopteroides syedi. Thubunaea hemidactylae Oshmarin & Demshin, 1972 from Hemidactylus frenatus Duméril & Bibron in Vietnam is considered a member of the genus Physalopteroides as P. hemidactylae (Oshmarin & Demshin, 1972) n. comb.

"Revisiting the past": a redescription of Physaloptera retusa (Nemata, Physalopteridae) from material deposited in museums and new material from Amazon lizards.

Physaloptera Rudolphi, 1819 is a genus of nematodes that includes approximately 100 species parasitic in vertebrates around the world. From these, approximately 30 occur in the Neotropical region, with nine reported from neotropical reptiles. Physaloptera spp. are recognized by their distinct morphology of the apical end and characters of the reproductive system. However, despite the fact that the morphological characters for species diagnosis have been firmly established, we frequently find identification problems regarding poorly detailed descriptions and poorly preserved specimens. These may lead to taxonomic incongruencies. Physaloptera retusa (Rudolphi, 1819) is the most common species of the genus and has been reported from several species of neotropical reptiles. Based on our reexaminations of nematode specimens identified as P. retusa from different museum collections, we provide a detailed redescription including the type material, voucher specimens and new specimens recovered currently and showed in this study with new morphological data obtained using light and scanning electron microscopy tools.

Range of metastrongylids (superfamily Metastrongyloidea) of public health and veterinary concern present in livers of the endemic lizard Gallotia galloti of Tenerife, Canary Islands, Spain.

BACKGROUND: Endemic lizards of the genus Gallotia are of high ecological value to the terrestrial ecosystem of the archipelago of the Canary Islands, being potent seed spreaders as well as an important component of the diet of other vertebrates. The endemic lizard Gallotia galloti in Tenerife has recently been reported to be a paratenic host of Angiostrongylus cantonensis, an invasive metastrongylid with zoonotic potential that is associated with rats as definitive hosts. However, microscopic examination of G. galloti tissue samples also revealed the presence of other metastrongylid larvae inside granulomas on the liver of this reptile. The aim of this study was to investigate the presence of helminths other than A. cantonensis in tissues of G. galloti from Tenerife. METHODS: A multiplex-nested PCR targeting the internal transcribed spacer 1 was designed that enabled the species-specific detection of A. cantonensis, Angiostrongylus vasorum, Aelurostrongylus abstrusus, Crenosoma striatum and Crenosoma vulpis. Liver samples from 39 G. galloti were analysed. RESULTS: Five metastrongylids were detected: A. cantonensis (15.4% of samples analysed), A. vasorum (5.1%), Ae. abstrusus (30.8%), C. striatum (30.8%) and undetermined metastrongylid sequences (12.8%). Co-infection was highly prevalent among the lizards which tested positive. CONCLUSIONS: The study provides a new specific tool for the simultaneous detection of a range of metastrongylids of veterinary importance as well as new data on the circulation of metastrongylids in an ecosystem dominated by lizards.

Genetic diversity, phylogenetic position, and co-phylogenetic relationships of Karyolysus, a common blood parasite of lizards in the western Mediterranean.

The genus Karyolysus was originally proposed to accommodate blood parasites of lacertid lizards in Western Europe. However, recent phylogenetic analyses suggested an inconclusive taxonomic position of these parasites of the order Adeleorina based on the available genetic information. Inconsistencies between molecular phylogeny, morphology, and/or life cycles can reflect lack of enough genetic information of the target group. We therefore surveyed 28 localities and collected blood samples from 828 lizards of 23 species including lacertids, skinks, and geckoes in the western Mediterranean, North Africa, and Macaronesia, where species of Karyolysus and other adeleorine parasites have been described. We combined molecular and microscopic methods to analyze the samples, including those from the host type species and the type locality of Karyolysus bicapsulatus. The phylogenetic relationship of these parasites was analyzed based on the 18S rRNA gene and the co-phylogenetic relationship with their vertebrate hosts was reconstructed. We molecularly detected adeleorine parasites in 37.9% of the blood samples and found 22 new parasite haplotypes. A phylogenetic reconstruction with 132 sequences indicated that 20 of the newly detected haplotypes clustered in a well-supported clade with another 18 sequences that included Karyolysus galloti and Karyolysus lacazei. Morphological evidence also supported that K. bicapsulatus clustered in this monophyletic clade. These results supported the taxonomic validity of the genus. In addition, we found some parasite haplotypes that infected different lizard host genera with ancient diverging histories, which suggested that Karyolysus is less host-specific than other blood parasites of lizards in the region. A co-phylogenetic analysis supported this interpretation because no significant co-speciation signal was shown between Karyolysus and lizard hosts.

Checklist of parasites associated with 'reptiles' in Northeast Brazil.

Reptiles, as well as other vertebrate groups, harbour a significant diversity of parasitic organisms, from nematodes and other helminths to viruses and bacteria. The Northeast is one of the richest regions in Brazil in terms of the reptile diversity, number of species and endemism. Parasites are diverse organisms and knowledge about the parasitic fauna of vertebrates is an important factor in understanding the ecological relationships between hosts and the environment. Studies on the parasitic fauna of reptiles in South America have increased in the past few years. The present review is a compilation of 122 studies published from 1924 to 2021. We present information on 101 species of reptiles from five groups (amphisbaenians, crocodile, testudines, snakes and lizards) and 183 parasitic taxa belonging to four phyla: Nematoda; Arthropoda; Platyhelminthes; and Acanthocephala. Nematodes were the most frequently recorded species. Lizards and snakes had more records of parasitism and higher levels of parasite richness and diversity. Ceará was the state with most studies and recorded cases of parasite-host association. The Caatinga and Atlantic Forest were the most investigated environments. The objective of this review was to contribute knowledge on the parasitic biodiversity in reptiles from Northeast Brazil, which may help identify gaps in our knowledge and guide future studies.

TONGUE WORM (PENTASTOMIDA) PARASITES OF NORTH AMERICAN HERPETOFAUNA: CHECKLIST OF SPECIES, IDENTIFICATION KEY, AND NEW STATE AND HOST RECORDS FROM MEXICO.

An updated checklist of tongue worms (Pentastomida) which parasitize wild North American amphibians and reptiles is presented: a total of 14 species grouped in 6 genera, 4 families, and 2 orders are registered; these infect a total of 58 species of reptiles and 3 amphibians in the region. An illustrated identification key for the taxa listed is proposed. Kiricephalus coarctatus (Diesing, 1860) (Porocephalidae) is recorded for the first time in the snakes Arizona elegans Kennicott, 1859 (Colubridae); Micrurus tener Baird and Girard, 1853 (Elapidae); and Bothrops asper (Garman, 1884) (Viperidae); the exotic Raillietiella taegueselfiRiley, McAllister, and Freed, 1988 (Raillietiellidae) is recorded in the exotic lizard Hemidactylus frenatus Duméril and Bibron, 1836 (Gekkonidae) for the first time, and in Hemidactylus turcicus (Linnaeus, 1758) (Gekkonidae) for the first time in Mexico, this is also the first time it is recorded in a species of lizard native of the Americas, Sceloporus cyanogenys Cope, 1885 (Phrynosomatidae), this latter record represents a parasite spillover event; finally, Porocephalus stilesiSambon, 1910 (Porocephalidae) is formally recorded for the first time in Mexico in the snake Bothrops asper.

New host and locality records of helminths' infection of seven lizards from Morocco.

Morocco has a great diversity of reptiles; more than 26% of the herpetofauna species are considered to be endemic. Nevertheless, there is little information available on helminth parasites of Moroccan lizards. The purpose of this article is to establish a helminth list using non-invasive methods for natural populations of seven lizard species: Acanthodactylus maculatus, Chalcides mionecton, Chalcides montanus, Chalcides polylepis, Quedenfeldtia moerens, Quedenfeldtia trachyblepharus, and Tarentola mauritanica. For each species, prevalence and intensity of infection were given as well as their relationship to some determinant parameters (sex, age class, size, altitude, and seasons). Four species of nematodes, Parapharyngodon micipsae, Pharyngodon mamillatus, Spauligodon auziensis, Thelandros alatus, and unassigned Spauligodon were found. Mean helminth intensity for the seven lizard species was 7.3 ± 16.2 SD (range = 1-92 in infected lizards), with total infection prevalence of 5.6%. Mixed infections were observed in Chalcides montanus and Chalcides polylepis co-infected by Pharyngodon mamillatus and Spauligodon sp. Furthermore, the intensity of infection by nematodes were significantly different among the seven studied species. The nematode infection in Chalcides mionecton were related to sex, host size, and altitude; in Chalcides polylepis to the host age; in Quedenfeldtia trachyblepharus to elevation, age, and host size; and in Tarentola Mauritanica to age, body size, seasons, and altitude. In conclusion, our study provides data about nine new host and locality records and the effect of some determinant factors on host parasitism.

Sarcocystis sp. infection (Apicomplexa: Sarcocystidae) in invasive California kingsnake Lampropeltis californiae (Serpentes: Colubridae) in Gran Canaria.

Invasive species pose a threat not only to biodiversity because they displace or compete with native fauna, but also because of the pathogens they can host. The Canary Islands are an Atlantic biodiversity hotspot threatened by increasing numbers of invasive species, including the California kingsnake Lampropeltis californiae, which was recently introduced to Gran Canaria. Seventy-seven snakes were examined for gastrointestinal parasites in 2019­2020. Sporocysts of Sarcocystis sp. were detected in 10 of them; detection of gamogonia stages in histological sections of 3 snakes confirmed the snake as a definitive host. Partial ssrDNA was amplified using SarcoFext/SarcoRext primers; an additional sequence of Sarcocystis was obtained from the tail muscle of the endemic Gran Canaria giant lizard Gallotia stehlini for a comparison. Identical ssrDNA sequences of unknown Sarcocystis sp. were obtained from 5 different snakes. Phylogenetic analysis showed that Sarcocystis sp. isolated from invasive California kingsnakes is unrelated to Sarcocystis provisionally considered S. stehlini from the endemic lizard. The dixenous coccidia are rarely reported to invade new predator­prey systems. However, the present data suggest that previously unknown Sarcocystis sp. is circulating among invasive snakes and as yet unknown vertebrate intermediate hosts, with undetermined consequences for the Gran Canaria ecosystem.

Haemosporidian infections in wild populations of Podarcis muralis from the Italian Peninsula.

Parasites can significantly influence the ecology, behaviour and physiology of their hosts sometimes with remarkable effects on their survivorship. However, endemic parasites or those not associated with obvious clinical disease have been partly neglected in the past decades comparatively to the most pathogenic ones. Apicomplexa are an important example of blood parasites that have been broadly investigated, although it can be difficult to determine the effects of infections at the population level, especially in widespread species. Such is the case of the common wall lizard (Podarcis muralis). We investigated 61 populations across Italy between 2008 and 2017 and recorded snout­vent length, latitude, date of collection and took blood samples for parasite count. We modelled parasite prevalence and load in a Bayesian framework. Parasites were present in all populations but 1 and in 13 of them all individuals were parasitized. We recorded almost identical responses for probability of infection and parasite load in both sexes, directly proportional to body size and inversely proportional to latitude, with a peak in cooler months. Therefore, haemosporidians can be very common in P. muralis, although their presence can vary significantly. Moreover, such a high prevalence makes it necessary to investigate to what extent haemosporidians affect hosts' survivorship, taking into consideration abiotic and biotic factors such as temperature, hormone levels and immune response.

A review of mites and ticks parasitizing rock lizards (Lacertidae: Darevskia).

Rock lizards of the genus Darevskia are interesting research models due to their asexual reproduction. Ectoparasitic mites and ticks of these lizards are poorly known, despite some of these chelicerates being vector pathogens of humans and wildlife. Here we document and curate previously known data on ectoparasitic Acari of rock lizards and, based on our extensive survey, provide an annotated list of these ectoparasitic arthropods (six tick species, one macronyssid species, and seven chigger species). We also provide new host records (Ixodes ricinus on Darevskia caucasica, D. dryada, D. mixta, and D. szczerbaki; Haemaphysalis sulcata on D. rudis; Odontacarus saxicolis on D. brauneri); and new geographical records (O. saxicolis in Russia and Georgia).

Pharyngodon mamillatus (Nematoda: Pharyngodonidae) in the ocellated skink Chalcides ocellatus (Squamata: Scincidae) from Egypt: Light and scanning electron microscopic studies.

Twenty-one Pharyngodon mamillatus were recovered from the large intestine of 4 out of 12 ocellated skink Chalcides ocellatus collected from the South Sinai desert, Egypt. The prevalence of infection was 33.33% (intensity 2-4). The recovered pharyngodonid was re-described based on light and scanning electron microscopy. According to the morphology, it was characterized by regular transverse annulations extending from the posterior margin of the lips to the level of the anus, triangular mouth opening was surrounded by three large bilobed lips possessing three papillae, oval-shaped excretory pore, slit-like vulva opening, and slit-like anal ventral opening at the posterior end which terminates with a tail filament. Here, the morphometric measurements of adult female P. mamillatus were given in this study. It has no intraspecific morphological variations from the previously described P. mamillatus, but it appeared with small range on biometric features. These variations may be accounted by host/environment attributes since they exhibit wide host and geographical spectra. The present study was applied for detailed morphological knowledge of the recovered P. mamillatus for strengthening their taxonomic validity. HIGHLIGHTS: The Pharyngodon mamillatus naturally parasite of the intestinal region of Chalcides ocellatus. The present study clarifies the morphological key for the description of P. mamillatus.

Shared haemogregarine infections in competing lacertids.

In parasite­host interactions host species may differ in their ability to fight parasitic infections, while other ecological interactions, including competition, may differentially alter their physiological state, making them even more susceptible to parasites. In this study, we analyse the haemogregarine blood parasites infecting two competing lizard species, Iberolacerta horvathi and Podarcis muralis, and explore host­parasite relationships under different host competition scenarios. Both species were infected with haemogregarine parasites belonging to the genus Karyolysus. Using the 18S rRNA gene, six new Karyolysus haplotypes were identified clustering with other Central and Eastern European samples, and widely shared between both lizard hosts. Haemogregarine infections were detected at all sampled sites with over 50% of individuals parasitized. Overall, I. horvathi was more frequently and also more intensely parasitized than P. muralis, with higher infection rates observed in syntopy. Males of both species tended to be more frequently infected and showed a higher infection intensity than conspecific females. The results suggest that parasitisation by haemogregarines may be relevant in the dynamics of the competitive relationship between these lizard species. More studies, including immunological response analysis, and the identification of the vectors are needed to better understand host­parasite relationships and competition.

Animal trait variation at the within-individual level: erythrocyte size variation and malaria infection in a tropical lizard.

High levels of within-individual variation (WIV) in reiterative components in plants such as leaves, flowers, and fruits have been shown to increase individual fitness by multiple mechanisms including mediating interactions with natural enemies. This relationship between WIV and fitness has been studied almost exclusively in plant systems. While animals do not exhibit conspicuous reiterative components, they have traits that can vary at the individual level such as erythrocyte size. It is currently unknown if WIV in animals can influence individual fitness by mediating the outcome of interactions with natural enemies as it has been shown in plants. To address this issue, we tested for a relationship between WIV in erythrocyte size, hemoparasite infection status, and body condition (a proxy for fitness) in a Caribbean anole lizard. We quantified the coefficient of variation of adult erythrocytes size in $n = 95$ infected and $n = 107$ non-infected lizards. We found higher degrees of erythrocyte size variation in infected lizards than in non-infected individuals. However, we found no significant relationship between infection status or erythrocyte size variation, and lizard body condition. These results suggest that higher WIV in erythrocyte size in infected lizards is not necessarily adaptive but likely a consequence of the host response to infection. Many hemoparasites destroy their host cells as part of their life cycle. To compensate, the host lizard may respond by increasing production of erythrocytes resulting in higher WIV. Our results emphasize the need to better understand the role of within-animal variation as a neglected driver or consequence of ecological and evolutionary interactions.