A new nematode (Nematoda: Cosmocercidae) from the lizard, Chamaeleo inturensis (Squamata: Chamaeleonidae) from the Democratic Republic of Congo

Maracaya africana n. sp. (Nematoda: Cosmocercidae) from the large intestine of the lizard Chamaeleo inturensis collected in Democratic Republic of Congo is described and illustrated. This is the first record of a species of Maracaya Diaz-Ungria (1963) for Africa. Light microscopy and scanning electron microscopy (SEM) studies revealed morphological differences in the structure of the male caudal end and cephalic end, which enabled us to differentiate these new species from the others. A key for determination of all species in the genus is provided.     

Two new species of Isospora Schneider, 1881 (Apicomplexa: Eimeriidae) from the flap-necked chameleon Chamaeleo dilepis (Sauria: Chamaeleonidae) in the Republic of Namibia

Two new species of Isospora Schneider, 1881 from flap-necked chameleons Chamaeleo dilepis Leach are described from the faeces of specimens collected in the Republic of Namibia. O?cysts of Isospora freedi n. sp. from one of four (25%) C. dilepis collected in the East Caprivi District are spherical to subspherical, with a smooth, colourless, bilayered wall, measure 23.7?×?21.2?μm and have a length/width (L/W) ratio of 1.1. The micropyle and the o?cyst residuum are absent but a polar granule is sometimes present. Sporocysts are ovoidal to ellipsoidal and 13.9?×?10.3?μm in size with prominent Stieda and sub-Stieda bodies; and the sporocyst residuum is composed of a compact mass of large globules. The sporozoites contain anterior and posterior refractile bodies with a nucleus between them. O?cysts of Isopora mandelai n. sp. from three of seven (43%) C. dilepis collected in the Outjo District are ellipsoidal to cylindroidal, with a smooth, colourless, bilayered wall, measure 36.9?×?31.0?μm and have an L/W ratio of 1.2. The micropyle, o?cyst residuum and polar granule are absent. Sporocysts are ovoidal to ellipsoidal, 15.3?×?11.1?μm in size and contain Stieda and sub-Stieda bodies; and the non-membranous sporocyst residuum is composed of granules of various sizes. The sporozoites contain anterior and posterior refractile bodies with a nucleus between them. These two new taxa represent the third and fourth coccidian species reported from C. dilepis.     

Morphogenesis of the prehensile autopodium in the common chameleon (Chamaeleo Chamaeleo)

This report documents the development of the autopodium of the common chameleon (Chamaeleo chamaeleo) using light microscopy, scanning electron microscopy, and transmission electron microscopy. Three main periods were distinguished during the morphogenesis of this structure. In the first period (stages 33-35 of chameleon development) the autopodium is paddle-shaped with a prominent apical ectodermal ridge (AER) along the distal margin. During this period the AER has structural features similar to other reptilian and avian vertebrates except for the scarcity or absence of gap junctions. The second period of autopodium morphogenesis (stage 36 of chameleon development) is characterized by the formation of a central cleft which divides this structure into two digital segments. In the forelimb the autopodial cleft occupies the space between digits 3 and 4. In the hindlimb the cleft occupies the space between digits 2 and 3. Mesenchymal cell death constitutes a constant feature during cleft formation. In addition to cell death during this process, we have observed that the AER flattens out in the zone of cleft formation while in the digital portions of the autopodium it takes on a polystratified appearance. In the last period of autopodial morphogenesis (stage 37 of chameleon development) digits become free by means of interdigital mesenchymal cell death.     

Eimeria hajeki n. sp. (Apicomplexa: Eimeriidae), a new coccidian parasite of the pygmy chameleon, Rampholeon temporalis (Matschie, 1892) (Reptilia: Chamaeleonidae) from Usambara Mountains, Tanzania.

Fecal samples from 10 pygmy chameleons, Rampholeon temporalis (Matschie, 1892), an endemic species of the Usambara Mountains in northeastern Tanzania, were examined for coccidian parasites. Two (20%) chameleons were found to be passing oocysts of Eimerio Schneider. Comparison with other species of Eimeria indicates that the coccidian found represents a new species. Sporulated oocysts of Eimeria hajeki n. sp. are oval, 30.2 (29-31) by 23.5 (22-25) microm, with a shape index (length/width) of 1.3 (1.2-1.4) and a 2-microm-thick rough, bilayered wall. Micropyle and polar granule are absent. Sporocysts are oval to rhomboidal, 10.8 (9-11.5) by 8.8 (7.5-10) microm, with a shape index of 1.2 (1.15-1.3) and a wall composed of 2 valves joined by a suture.     

Diet and conservation implications of an invasive chameleon, <Emphasis Type=Italic>Chamaeleo jacksonii</Emphasis> (Squamata: Chamaeleonidae) in Hawaii

We summarize information on current distribution of the invasive lizard Chamaeleo jacksonii and predict its potential distribution in the Hawaiian Islands. Potential distribution maps are based on climate models developed from known localities in its native range and its Hawaiian range. We also present results of analysis of stomach contents of a sample of 34 chameleons collected from native, predominantly dryland, forest on Maui. These data are the first summarizing prey range of this non-native species in an invaded native-forest setting. Potential distribution models predict that the species can occur throughout most of Hawaii from sea level to >2,100 m elevation. Important features of this data set are that approximately one-third of the diet of these lizards is native insects, and the lizards are consuming large numbers of arthropods each day. Prey sizes span virtually the entire gamut of native Hawaiian arthropod diversity, thereby placing a large number of native species at risk of predation. Our dietary results contrast with expectations for most iguanian lizards and support suggestions that chameleons comprise a third distinct foraging-mode category among saurians. The combination of expanding distribution, large potential range size, broad diet, high predation rates, and high densities of these chameleons imply that they may well become a serious threat to some of the Hawaiian fauna.     

A Late Campanian sphenodontid (Reptilia, Diapsida) from northern Patagonia

The fossil record of sphenodontids in the Southern Hemisphere is much longer than in Laurasia, where they became extinct after Early Cretaceous times. Recent works demonstrated the persistence of at least eilenodontine sphenodontids until the ‘mid’-Cretaceous of Patagonia. Focused examination of the Los Alamitos Formation collections provided remains of Late Campanian sphenodontids. Although the phylogenetic position of these remains is still uncertain, they belong to a new, unrecorded species of sphenodontid perhaps related to opisthodontians or primitive, toothed sapheosaurs. To cite this article: S. Apesteguía, C. R. Palevol 4 (2005).     

First procolophonid (Reptilia,Parareptilia) from the Lower Triassic of Madagascar

Lasasaurus beltanae nov. gen. nov. sp., a new procolophonid (Reptilia, Parareptilia) from the Lower Triassic of Madagascar, is represented by a single partial skeleton preserved in a ferro-calcareous nodule from the Middle Sakamena Formation, in the North of the island. This new taxon is unique in possessing peculiar, fine and dendritic crests running along the posterolateral side of the squamosal, widely spaced maxillary teeth, subparallel mesiodistal ridges connecting maxillary teeth to the tooth row, and a strongly acute anterior margin of the copula (hyoid bone). This well-preserved specimen belongs to a juvenile individual. The inclusion of L. beltanae nov. gen. nov. sp. in a phylogenetic analysis suggests that it is close to Theledectinae, Procolophoninae, and Leptopleurinae, though their respective relationships are uncertain. This specimen is the first procolophonid described from Madagascar and represents a minor terrestrial component of a coastal vertebrate assemblage dominated by amphibious to fully-aquatic taxa.     

Six new species of coccidia (Apicomplexa: Eimeriidae) from East African chameleons (Sauria: Chamaeleonidae)

Coprological examination of 83 East African chameleon specimens revealed 32.5% prevalence of coccidian parasites. Six species are described as new: Eimeria tilburyi n. sp. from Chamaeleo jacksonii has cylindrical oocysts, 28.9 (26-33) x 16.0 (14-18) microm and occasionally a small polar granule. Sporocysts are oval to ellipsoidal, 10.6 (9-12) x 7.2 (6-8) microm, without Stieda and substieda bodies; endogenous stages were found in the gall bladder. Oocysts of Eimeria largeni n. sp. from Chamaeleo gracilis are broadly cylindrical, 31.2 (29.5-34) x 19.3 (18.5-20) microm, with 1-3 polar granules. Sporocysts are oval, 10.2 (10-11) x 7.6 (7-8.5) microm, without Stieda and substieda bodies. Eimeria bohemii n. sp. from Chamaeleo melleri has cylindrical oocysts, 25.0 (24-26) x 14.0 (13-15) microm, without a polar granule. Sporocysts are broadly oval, 9.4 (9-10) x 6.5 (6-7) microm, without Stieda and substieda bodies. Isospora wildi n. sp. from Chamaeleo dilepis has subspherical to broadly oval oocysts, 25 (22-28) x 21.4 (18-24) microm, with a smooth wall 1 microm thick. Sporocysts are broadly oval to ellipsoidal, 12.3 (12-13) x 9.7 (9-10) microm, with Stieda and substieda bodies. Oocysts of Isospora necasi n. sp. from C. melleri are subspherical to broadly oval, 26.6 (21-30) x 24.3 (20-27) microm, with a velvetlike wall 2 microm thick. Sporocysts are broadly ellipsoidal, 12.8 (12-14) x 9.8 (9-10) microm, with slightly pointed end and with Stieda and substieda bodies. Oocysts of Isospora munriyu n. sp. from C. jacksonii are spherical to subspherical, 23.6 (21.5-25) x 21.9 (21-23) microm, with a finely granulated wall 1.5 microm thick. Sporocysts are broadly ellipsoidal, 12.4 (12-13) X 8.7 (8-10) microm, with Stieda and substieda bodies.     

Yaguarasaurus columbianus (Reptilia,Mosasauridae), a primitive mosasaur from the Turonian (upper cretaceous) of Colombia

New remains of Yaguarasaurus columbianus found in the Turonian beds of the upper valley of the Magdalena River, in Colombia, are described. Three aspects of the cranial morphology of Y. columbianus are of particular interest. First, its morphology is one of the most primitive among mosasaurs; second, it exhibits most similarities to the cranial morphology of the aigialosaurs; and finally, it exhibits some traits that are unknown in other mosasaurs, including certain cranial features that resemble those of the terrestrial varanoids.     

Phylogenetics of the southern African dwarf chameleons, Bradypodion (Squamata: Chamaeleonidae)

The taxonomic relationships within the dwarf chameleons (Bradypodion) of southern Africa have long been controversial. Although informal phenotypic groups have been suggested, the evolutionary relationships among the 15 recognised species in southern Africa have not been previously investigated. To investigate the relationships among species within this genus, fragments of two mitochondrial genes (16S ribosomal RNA and ND2) were sequenced and analysed using maximum parsimony, maximum likelihood and Bayesian inference. All analyses showed congruent topologies, revealing at least 5 well-supported clades distributed across distinct geographic regions. The mtDNA gene tree indicated that in many instances, geographic location has played a role in shaping the evolution of this group, and that the previously suggested phenotypic groupings do not adequately reflect evolutionary relationships. Furthermore, it appears that some of the currently recognised species (described on morphology) are polyphyletic for mitochondrial sequences, most notably those occurring in the isolated forest patches of north-eastern South Africa, near the Drakensberg Escarpment.     

Global diversity of crocodiles (Crocodilia,Reptilia) in freshwater

Living crocodilians include the 24 species of alligators, caimans, crocodiles and gharials. These large semi-aquatic ambush predators are ubiquitous in freshwater ecosystems throughout the world’s tropics and warm temperate regions. Extant crocodilian diversity is low, but the group has a rich fossil record in every continental deposit. Most populations suffered from over-hunting and habitat loss during the twentieth century and even though some species remain critically endangered others are real success stories in conservation biology and have become important economic resources. Guest editors: E. V. Balian, C. Lévêque, H. Segers & K. Martens Freshwater Animal Diversity Assessment     

Five new species of coccidia (Apicomplexa: Eimeriidae) from Madagascan chameleons (Sauria: Chamaeleonidae)

Coprological examination of 19 Madagascan chameleons of the genera Furcifer and Brookesia revealed the presence of five new coccidian species. Isospora brygooi n. sp. from Furcifer pardalis has spherical to subspherical oöcysts with a slightly pitted wall, 20.7 (17–24.5) × 19.3 (16–23) m and broadly ellipsoidal sporocysts, 12.2 (11.5–13) × 8.1 (8–8.5) m, with Stieda and substieda bodies. Oöcysts of Eimeria glawi n. sp. from Furcifer pardalis are cylindrical to ellipsoidal, 27.7 (26–29.5) × 18.4 (17–19) m, with ellipsoidal sporocysts, 7.3 (6.5–8) × 5.2 (5–5.5) m. E. vencesi n. sp. described from F. pardalis has spherical to subspherical oöcysts, 14.3 (13–15.5) × 13.0 (12–13) m, with small granules, one to three globular polar granules and ellipsoidal sporocysts, 7.3 (6.5–8) × 5.2 (5–5.5) m. E. worthi n. sp., described from Furcifer oustaleti has spherical oöcysts, 17.9 (17.5–19.0) × 15.0 (14.5–16.0) m without a polar granule and ellipsoidal to cylindroidal sporocysts, 8.2 (7.0–9.5) × 5.8 (5.0–6.5) m. Oöcysts of E. brookesiae n. sp. from Brookesia decaryi are cylindrical, 25.6 (23–27) × 15.0 (13–16) m with ellipsoidal sporocysts, 10.1 (9–11) × 6.9 (6–7) m. Endogenous development of E. vencesi is confined to the intestine, while that of E. glawi occurs in the gall-bladder.     

The skull of Cteniogenys, a choristodere (Reptilia: Archosauromorpha) from the Middle Jurassic of Oxfordshire

The genus Ctemogenys was originally described as a lizard on the basis of isolated jaw fragments from the Upper Jurassic deposits of Como Bluff, Wyoming. The discovery of new material from a Middle Jurassic locality at Kirtlington, Oxfordshire, showed that Cteniogenys was not a lizard, but an early choristodere. The skull is represented by a collection of isolated bones, associated on the basis of fit and dermal sculpture pattern. The bones are here described and compared with those of the Late Cretaceous and Palaeocene choristoderes Champsosaurus and Simoedosaurus. Allowing for the much smaller size of the Middle Jurassic form, there is a close correspondence between the isolated bones of the three genera. Comparison with known choristoderes, based on an analysis of 53 derived character states, suggests that Ctemogenys is the most primitive of known genera. In general, the character states shared by all choristoderes support recent analyses which conclude that choristoderes arc derived from archosauromorph diapsids, not lepidosauromorphs as once thought. At Kirtlington, Cteniogenys forms part of a diverse microvertebrate assemblage including amiids, sharks, frogs, salamanders, lizards, mammals, crocodiles, pterosaurs, turtles and small dinosaurs.