The parasite fauna of Neotropical reptiles is poorly known, and the number of parasites described in these hosts does not seem to correspond to the actual species diversity in this zoogeographical region. This also applies to tapeworms such as proteocephalids, which are rarely found in reptiles and are strictly specific to their reptilian hosts. In the present paper, three new species of Ophiotaenia La Rue, 1911 are described from three dipsadine snake species (Squamata: Colubridae) in Ecuador, namely O. jeanmarctouzeti sp. n. from the Neotropical blunt-headed treesnake Imantodes cenchoa (Linnaeus), O. barraganae sp. n. from the beautiful calico snake Oxyrhopus formosus (Wied-Neuwied) and O. velascoae sp. n. from the forest flame snake Oxyrhopus petolarius (Linnaeus). The new species are characterised by type 1 uterine development, the number and distribution of testes, the size of the scolex and other metric features. As no molecular data are available on the specimens collected more than 35 years ago, the phylogenetic relationships of the individual taxa are not known.
- MeSH
- Cestoda * classification isolation & purification MeSH
- Cestode Infections veterinary parasitology epidemiology MeSH
- Colubridae * parasitology MeSH
- Species Specificity MeSH
- Phylogeny MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Ecuador MeSH
- Keywords
- Bojga,
- MeSH
- Colubridae MeSH
- Rodent Control * methods MeSH
- Acetaminophen MeSH
- Introduced Species * MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
The process of species diversification is often associated with niche shifts in the newly arising lineages so that interspecific competition is minimized. However, an opposing force known as niche conservatism causes that related species tend to resemble each other in their niche requirements. Due to the inherent multidimensionality of niche space, some niche components may be subject to divergent evolution while others remain conserved in the process of speciation. One such possible component is the species' climatic niche. Here, we test the role of climatic niche evolution on the diversification of the Old World cat snakes of the genus Telescopus. These slender, nocturnal snakes are distributed in arid and semiarid areas throughout Africa, southwest Asia and adjoining parts of Europe. Because phylogenetic relationships among the Telescopus species are virtually unknown, we generated sequence data for eight genetic markers from ten of the 14 described species and reconstructed a time-calibrated phylogeny of the genus. Phylogenetic analysesindicate that the genus is of considerably old origin that dates back to the Eocene/Oligocene boundary. Biogeographical analyses place the ancestor of the genus in Africa, where it diversified into the species observed today and from where it colonized Arabia and the Levant twice independently. The colonization of Arabia occurred in the Miocene, that of the Levant either in the Late Oligocene or Early Miocene. We then identified temperature and precipitation niche space and breadth of the species included in the phylogeny and examined whether there is phylogenetic signal in these climatic niche characteristics. Despite the vast range of the genus and its complex biogeographic history, most Telescopus species have similar environmental requirements with preference for arid to semiarid conditions. One may thus expect that the genus' climatic niche will be conserved. However, our results suggest that most of the climatic niche axes examined show no phylogenetic signal, being indicative of no evolutionary constraints on the climatic niche position and niche breadth in Telescopus. The only two variables with positive phylogenetic signal (temperature niche position and precipitation niche breadth) evolved under the Brownian motion model, also indicating no directional selection on these traits. As a result, climatic niche evolution does not seem to be the major driver for the diversification in Telescopus.
- MeSH
- Principal Component Analysis MeSH
- Bayes Theorem MeSH
- Biological Evolution * MeSH
- Time Factors MeSH
- Colubridae classification MeSH
- Rain MeSH
- Phylogeny MeSH
- Phylogeography * MeSH
- Calibration MeSH
- Climate * MeSH
- Temperature MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Africa MeSH
- Arabia MeSH
Telescopus pulcher is an enigmatic colubrid snake only known from the holotype and paratype specimens described from 'Migiurtinia' in Puntland (Somalia) in 1935. Herein we recorded the third and fourth-ever known specimens of this species from the Toon village, Woqooyi Galbeed Region, and 15 km southeast of Sheikh, Saahil Region, Somaliland. The species is endemic to Somaliland and adjoining parts of Ethiopia and Puntland. Data on morphology and natural history, as well as the first photographs of live specimens are provided. We also provide a detailed description of the paratype. The coloration of the species resembles that of the vipers of the genus Echis and we hypothesize that T. pulcher mimics these common and sympatric vipers in the Horn of Africa.
Squamate reptiles appear to lack the specialized His-Purkinje system that enables the cardiac ventricle to be activated from apex to base as in mammals and birds. Instead, activation may simply spread from where the atrioventricular canal connects to the base. Gja5, which encodes Cx40, which allows fast impulse propagation, was expressed throughout the ventricles of developing anole lizards. Activation was optically recorded in developing corn snake and central bearded dragon. Early embryonic ventricles were broad in shape, and activation propagated from the base to the right. Elongated ventricles of later stages were activated from base to apex. Before hatching of the snake, the ventricle developed a cranial extension on the left and activation propagated from the base to the caudal apex and the cranial extension. In squamate reptiles, the pattern of electrical activation of the cardiac ventricle is dependent on the position of the atrioventricular canal and the shape of the ventricle.
- MeSH
- Colubridae embryology MeSH
- Lizards embryology MeSH
- Heart Ventricles embryology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
To date, only a few species of Hepatozoon Miller, 1908 have been described from amphibians and reptiles of South Africa, including two species from anuran hosts, three from saurians, one from chelonians, and two from ophidians. Hepatozoon bitis (Fantham, 1925) and Hepatozoon refringens (Sambon et Seligmann, 1907), parasitising Bitis arientans (Merrem) and Pseudoaspis cana (Linnaeus), respectively, were described in the early 1900s and since then there have been no further species of Hepatozoon described from snakes in South Africa. Blood smears, used in peripheral blood haemogregarine stage morphometrics, and whole blood used in molecular characterisation of haemogregarines were collected from the caudal vein of six snakes of three species, namely Philothamnus hoplogaster (Günther), Philothamnus semivariegatus (Smith) and Philothamnus natalensis natalensis (Smith). For comparison, a comprehensive table summarising available information on species of Hepatozoon from African snakes is presented. Haemogregarines found infecting the snakes from the present study were morphologically and molecularly different from any previously described from Africa and are thus here described as Hepatozoon angeladaviesae sp. n. and Hepatozoon cecilhoarei sp. n. Both haemogregarine species were observed to cause considerable dehaemoglobinisation of the host cell, in case of infection with H. angeladaviesae resulting in a characteristic peripheral undulation of the host cell membrane and karyorrhexis. To the authors' knowledge, these are the first haemogregarines parasitising snakes of the genus Philothamnus Smith described using both morphological and molecular characteristics in Africa.
- MeSH
- Colubridae parasitology MeSH
- Eucoccidiida classification cytology physiology MeSH
- Host-Parasite Interactions * MeSH
- Coccidiosis parasitology physiopathology veterinary MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- South Africa MeSH
The genus Rhynchocalamus comprises three species distributed in Southwest Asia. Little is known about them, most probably because of their secretive fossorial lifestyle. The poor knowledge of the genus is even underscored by the fact that its phylogenetic affinities remained unclear until very recently. The least known of the species, Rhynchocalamus arabicus, is known only from the holotype collected in Aden, Yemen, and it has not been observed since its description in 1933. Here we provide a second record for this species, which represents the first record of this genus for Oman. This extends its range in southern Arabia by more than 1000 km. The observed specimen was determined as R. arabicus on the basis of its similarity in size, color, and scalation with the holotype. Furthermore, we sequenced three mitochondrial (12S, 16S, cytb) and one nuclear (cmos) genes for R. arabicus and for two individuals of R. melanocephalus and one R. satunini and inferred the phylogenetic relationships of all currently recognized species of the genus for the first time. The results of our phylogenetic analyses indicate that Rhynchocalamus is a member of the Western Palearctic clade of Colubrinae and is sister to Lytorhynchus, with which it forms a very well supported clade and shares some morphological characters. As our results show, R. satunini is the basal lineage of the genus and R. melanocephalus is sister to R. arabicus.
- MeSH
- Animal Structures anatomy & histology growth & development MeSH
- Colubridae anatomy & histology classification genetics growth & development MeSH
- Phylogeny * MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Animal Distribution MeSH
- Organ Size MeSH
- Body Size MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Oman MeSH
Understanding how species responded to past climate change can provide information about how they may respond to the current global warming. Here we show how a European reptile species responded to the last natural global warming event at the Pleistocene-Holocene transition that led to the Holocene climatic optimum approximately 5000-8000 years ago. The Aesculapian snake, Zamenis longissimus, is a thermophilous species whose present-day distribution in the southern half of Europe is a remnant of much wider range during the Holocene climatic optimum when populations occurred as far north as Denmark. These northern populations went extinct as the climate cooled, and presently the species is extinct from all central Europe, except few relic populations in locally suitable microhabitats in Germany and the Czech Republic. Our phylogenetic and demographic analyses identified two major clades that expanded from their respective western and eastern refugia after the last glacial maximum (18,000-23,000 years ago) and contributed approximately equally to the present range. Snakes from the relic northern populations carried the Eastern clade, showing that it was primarily the snakes from the eastern, probably Balkan, refugium that occupied the central and northern Europe during the Holocene climatic optimum. Two small, deep-branching clades were identified in near the Black Sea and in Greece. These clades provide evidence for two additional refugia, which did not successfully contribute to the colonization of Europe. If, as our results suggest, some populations responded to the mid-Holocene global warming by shifting their ranges further north than other populations of the same species, knowing what populations were able to expand in different species may provide information about what populations will be important for the species' ability to cope with the current global warming.
- MeSH
- Colubridae classification genetics MeSH
- Phylogeny MeSH
- Phylogeography MeSH
- Haplotypes MeSH
- DNA, Mitochondrial genetics MeSH
- Evolution, Molecular MeSH
- Climate MeSH
- Likelihood Functions MeSH
- Sequence Analysis, DNA MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Europe MeSH
Ophiotaenia georgievi sp. n. (Proteocephalidea: Proteocephalinae) is described from the intestine of endemic colubrid snake Leioheterodon geayi Mocquard (Colubridae) from Antananarivo in Madagascar. The new species is the first species of Ophiotaenia La Rue, 1911 reported from Madagascar. It differs from all Ophiotaenia species parasitic in African snakes in the possession of a three-layered embryophore of eggs (other African species have two-layered embryophore). Furthermore, O. georgievi can be distinguished by the number of testes (92-140), width of the scolex (225-235 jm), total body length (57 mm), cirrus-sac length/proglottis width ratio (19-32%), and number of lateral uterine diverticula (23-28 on each side). Ophiotaenia georgievi represents the second proteocephalidean cestode reported from Madagascar, the first one being Deblocktaenia ventosaloculata (Deblock, Rosé et Broussart, 1962), a parasite from Ithycyphus miniatus. A list of Ophiotaenia species parasitic in venomous and non-venomous snakes is provided and possible existence of other new congeneric species in snakes from Madagascar is discussed.
Animals are ancestrally important stimuli for humans who pay disproportional attention to animal objects and exhibit an outstanding ability to categorize animal species, especially those most relevant to them. Humans as well as other primates perceive snakes as ambivalent stimuli that elicit unspecific arousal and attention. We assessed human aesthetic preferences toward milk snakes, the traditional model for studies of Batesian mimicry. The genus is fairly uniform in size and shape, but includes a great variety of color forms; some possessing aposematic patterns while others being rather cryptic. This provides an opportunity to test which features are responsible for positive aesthetic evaluation of the species. We asked the respondents to rank 34 pictures of milk snakes according to perceived beauty. The sets (whole bodies, heads, and skin fragments) covered most of naturally occurring variation in milk snake appearance. While ranking the beauty, the respondents spontaneously classified the species according to two dimensions. In each set, one of the dimensions corresponds to perceived beauty. The respondents' ranking revealed several distinct clusters of species instead of a continuous gradient. The species clustered in a similar way irrespective of evaluated set. One dimension of the ranking associated with the relative representation of red color and the number of transversal stripes, the other corresponded to a low proportion of red and a high proportion of black color. When the whole body of the snake is evaluated, aposematic coloration contributes to its perceived beauty. In conclusion, humans showed a surprising ability to classify milk snake patterns; they repeatedly formed the same distinct groups of species, thus completing a process that resembles unsupervised categorization.
- MeSH
- Principal Component Analysis MeSH
- Colubridae anatomy & histology classification MeSH
- Esthetics psychology MeSH
- Head anatomy & histology MeSH
- Cognition MeSH
- Beauty MeSH
- Skin anatomy & histology MeSH
- Humans MeSH
- Molecular Mimicry MeSH
- Pattern Recognition, Visual MeSH
- Cluster Analysis MeSH
- Photic Stimulation MeSH
- Color Perception MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
