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Up to 10 males were reported to sire clutches of crocodilian eggs but review of the underlying study designs raised questions of potential upward bias of inferred sire numbers. To test this premise, different scenarios were explored using a published dataset of 16 known single-sire saltwater crocodile pairs and their offspring which were originally confirmed using a 11 loci microsatellite panel in CERVUS. Varying the number of microsatellites, omitting one or both parental genotypes and using different parentage analysis techniques revealed that total allele number, rather than number of loci, determined inferred sire accuracy in two opposing ways. Using the single-locus minimum method and GERUD, which both require prior knowledge of family groupings (i.e., nests), fewer alleles (and loci) accurately inferred only one father. In contrast, CERVUS and COLONY required all 11 loci (65 alleles) and both parental genotypes to (a) assign correct family groups and (b) infer the correct sire number, except in one family where two sires were equally assigned based on their number of homozygous loci. When less genotype information was provided, CERVUS and COLONY inferred up to six and seven sires, respectively. Given this data is from confirmed single-sire matings, and yet up to seven sires could be inferred, the significance of inappropriate study design is clearly demonstrated. Consideration should be carefully given to genotype data, particularly those collected specifically for population diversity studies, which are also used to infer multiple paternity because the underlying data collection assumptions are not equivalent between the two outcomes., Competing Interests: The author declares no conflict of interest., (© 2022 The Author. Ecology and Evolution published by John Wiley & Sons Ltd.)

Background Little is known about the diversity, phylogenetic relationships, and biogeography of trypanosomes infecting non-mammalian hosts. In this study, we investigated the influence of host species and biogeography on shaping the genetic diversity, phylogenetic relationship, and distribution of trypanosomes from South American alligatorids and African crocodilids. Methods Small Subunit rRNA (SSU rRNA) and glycosomal Glyceraldehyde Phosphate Dehydrogenase (gGAPDH) genes were employed for phylogenetic inferences. Trypanosomes from crocodilians were obtained by haemoculturing. Growth behaviour, morphology, and ultrastructural features complement the molecular description of two new species strongly supported by phylogenetic analyses. Results The inferred phylogenies disclosed a strongly supported crocodilian-restricted clade comprising three subclades. The subclade T. grayi comprised the African Trypanosoma grayi from Crocodylus niloticus and tsetse flies. The subclade T. ralphi comprised alligatorid trypanosomes represented by Trypanosoma ralphi n. sp. from Melanosuchus niger, Caiman crocodilus and Caiman yacare from Brazilian river basins. T. grayi and T. ralphi were sister subclades. The basal subclade T. terena comprised alligatorid trypanosomes represented by Trypanosoma terena n. sp. from Ca. yacare sharing hosts and basins with the distantly genetic related T. ralphi. This subclade also included the trypanosome from Ca. crocodilus from the Orinoco basin in Venezuela and, unexpectedly, a trypanosome from the African crocodilian Osteolaemus tetraspis. Conclusion The close relationship between South American and African trypanosomes is consistent with paleontological evidence of recent transoceanic dispersal of Crocodylus at the Miocene/Pliocene boundaries (4-5 mya), and host-switching of trypanosomes throughout the geological configuration of South American hydrographical basins shaping the evolutionary histories of the crocodilians and their trypanosomes. [ABSTRACT FROM AUTHOR]

‘Crocodylus’pigottiis a relatively small crocodylid from the Miocene of Rusinga Island in Lake Victoria, Kenya. Known only from one relatively complete skull and limited, fragmentary, referred material, ‘Crocodylus’pigottilacks a detailed description. Moreover, recent analyses have shown ‘Crocodylus’pigottito be an osteolaemine crocodylid, more closely related to the extant dwarf crocodiles (Osteolaemus) than to trueCrocodylus. Here, we describe numerous new remains of ‘Crocodylus’pigottirecovered from localities within the Fossil Bed Member of the Hiwegi Formation at Kaswanga Point, Rusinga Island. We recovered parts of several individuals and report on previously unknown parts of the anatomy, provide an updated phylogenetic analysis, and reallocate the species ‘Crocodylus’pigottito a new genus,Brochuchus. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free atwww.tandfonline.com/UJVP [ABSTRACT FROM PUBLISHER]

Abstract: New fossil remains from the Tortonian of Scontrone (Abruzzo, Southern Italy) provide further information on crocodylids with a generalized rostral morphology that inhabited the Mediterranean area during the late Miocene. Particularly informative is the nearly complete right dentary SCT 276. Thanks to the fact that the third and fourth alveoli are clearly separated by a bony septum and are markedly different in size, the fourth being much larger than the third, it is possible to exclude that SCT 276 belonged to the alligatoroid Diplocynodon and to tentatively refer it to cf. Crocodylus sp. This genus has been previously identified on a phylogenetic basis in the same Apulo-Abruzzi palaeobioprovince (Gargano Terre Rosse, Messinian-Zanclean, Crocodylus sp.), and it is likely present also in the Tusco-Sardinian palaeobioprovince (Monte Bamboli, Tortonian, cf. Crocodylus sp.). SCT 276 currently represents the oldest possible evidence of the presence of Crocodylus; it proves that this taxon could have already reached Europe during the Tortonian, well before the Messinian Salinity Crisis that is traditionally considered as the event that caused several trans-Mediterranean dispersals. Furthermore, it is tempting to associate the absence of alligatoroids and the presence of crocodylids in these palaeobioprovinces (actually systems of islands) to the different behavioural, morphological and physiological traits of extant alligatorids and crocodylids, which render rather salt-intolerant the former and salt-tolerant the latter. [Copyright &y& Elsevier]

The activity pattern, behavioural activity and interspecific interactions of smooth-coated otter (Lutrogale perspicillata) with crocodilians viz. gharial (Gavialis gangeticus) and mugger (Crocodylus palustris) was examined by monitoring four radioimplanted otters in the National Chambal Sanctuary, India. Based on the percentage of active telemetry recordings, the observed overall activity patterns of otters were in the form of a bimodal curve in which two periods of high activity were separated by a period of relative inactivity. In summer, the relative period of inactivity was greater than the winter and monsoons. Otters were more diurnal during winter than in summer or monsoon. Travelling and grooming were the most prevalent activities recorded during 422 sightings. Though the habitats and the diet of otters overlapped with gharial and mugger, their diurnal activity pattern was different and spatially they maintained a mutually agreeable strategy to avoid conflicts in sharing resources for basking and grooming [ABSTRACT FROM AUTHOR]

The Nile crocodile (Crocodylus niloticus) is an iconic or keystone species in many aquatic ecosystems. In order to understand the abundance, distribution, and population trends of Nile crocodiles in Gonarezhou National Park (GNP), southeastern Zimbabwe, we carried out 4 annual aerial surveys, using a Super Cub aircraft, along 3 major rivers, namely, Save, Runde and Mwenezi, between 2008 and 2011. Our results show that Runde River was characterised by a significant increase in Nile crocodile abundance whereas both Save and Mwenezi rivers were characterised by non-significant increases in Nile crocodile abundance. Overall, we recorded a significant increase in total Nile crocodile population in the three major rivers of the GNP. The non-significant increase in Nile crocodiles in the Mwenezi and Save rivers was likely due to habitat loss, through siltation of large pools, and conflicts with humans, among other factors. We suggest that GNP management should consider halting crocodile egg collection in rivers with low crocodile populations and continuously monitor the crocodile population in the park. [ABSTRACT FROM AUTHOR]

The American crocodile, Crocodylus acutus, is widely distributed in the American neotropics. It is endangered throughout most of its range and is listed as vulnerable by the International Union for the Conservation of Natural Fauna and Flora (IUCN) and on Appendix I of the Convention for the International Trade in Endangered Species of Wild Flora and Fauna (CITES). Despite this listing, there are few published reports on population status throughout most of its range. We investigated the status of the C. acutus, at several locations along the Pacific coast of Costa Rica. We carried out spotlight and nesting surveys from 2007-2009 along the Costa Rican Pacific coast in four distinct areas, coastal areas of Las Baulas (N=40) and Santa Rosa (N=9) National Parks and the Osa Conservation Area (N=13), and upriver in Palo Verde National Park (N=11). We recorded crocodile locations and standard environmental data at each observation. Encounter rates, population structure, distribution within each area and data on successful nesting (presence of hatchlings, nests, etc) were determined. We attempted to capture all crocodiles to record standard morphometrics. A total of 586 crocodiles were observed along 185.8km of survey route. The majority of animals encountered (54.9%) were either hatchlings (<0.5m) or juveniles (0.5-1.25m). The average non-hatchling encounter rate per survey for the Pacific coast was 3.1 crocodiles/km, with individual encounter rates ranging from 1.2 crocodiles/km to 4.3 crocodiles/ km in Las Baulas National Park and the Osa Conservation Area respectively. Distribution of size classes within the individual locations did not differ with the exception of Santa Rosa and Las Baulas National Parks, where hatchlings were found in water with lower salinities. These were the first systematic surveys in several of the areas studied and additional work is needed to further characterize the American crocodile population in Costa Rica. [ABSTRACT FROM AUTHOR]

Body condition factors have been used as an indicator of health and well-being of crocodilians. We evaluated body condition of Morelet's Crocodiles (Crocodylus moreletii) in northern Belize in relation to biotic (size, sex, and habitat) and abiotic (location, water level, and air temperature) factors. We also tested the hypothesis that high water levels and warm temperatures combine or interact to result in a decrease in body condition. Size class, temperature, and water level explained 20% of the variability in condition of Morelet's Crocodiles in this study. We found that adult crocodiles had higher condition scores than juveniles/subadults but that sex, habitat, and site had no effect. We confirmed our hypothesis that warm temperatures and high water levels interact to decrease body condition. We related body condition of Morelet's Crocodiles to natural fluctuations in air temperatures and water levels in northern Belize, providing baseline conditions for population and ecosystem monitoring. [ABSTRACT FROM AUTHOR]

Mercury (Hg) concentrations in the Amazon are generally high, but no studies have been published on Hg concentrations in caimans (Alligatoridae) from the region. Aiming for sizes representative of caimans traded for food in the Amazon, we measured Hg concentration in tail muscle of spectacled caiman ( Caiman crocodilus crocodilus) and black caiman ( Melanosuchus niger) from the Purus River basin. The information on Hg concentration in caimans from this area is important because of the potential health risk to humans and other animals that eat them as well as the potential use of these top-level predators as bioindicators. There were no significant interspecific or sex differences in Hg concentrations. The mean Hg concentration was 291.2 μg/kg in C. c. crocodilus and 193.9 μg/kg in M. niger. A significant positive correlation between Hg concentration and size was found for M. niger ( p = 0.005) but not for C. c. crocodilus. Our Hg sample from M. niger corresponded to the size of M. niger collected for commercial trade, but our Hg sample from C. c. crocodilus turned out to be significantly smaller than the trade samples ( p = 0.004), but this difference is not pertinent in the absence of a correlation between size and Hg concentration for this species. Although there are no standards for reptile meat, both species had mean Hg concentrations lower than the maximum allowable level of 500 μg/kg Hg recommended by the World Health Organization and by the Brazilian Health Ministry for fish. However, by calculating daily consumptions limits and number of meals per month that can be safely consumed, we found that consumers who eat caimans frequently may be at risk for Hg-related health problems. [ABSTRACT FROM AUTHOR]

Abstract: Crocodilians have temperature-dependent sex determination (TSD) in which incubation temperature determines sex of embryo. Global warming is expected to alter hatchling sex ratio, leading to the extinction of small populations. Regional climate influence on crocodile nest microclimate and hatchlings'' characteristics is poorly known. Here, microclimate in natural nests of American crocodile (Crocodylus acutus) and its relation with incubation length, hatchling sex and nesting success was studied in Banco Chinchorro Biosphere Reserve (Mexico) from 2007 to 2010. Temperature and relative humidity in different locations within and outside the nests were registered by data loggers. Incident solar radiation above nest was calculated from hemispheric photographs. Incubation length, proportion of hatchling reaching complete development and hatchling sex were determined at hatching. Nest temperatures exhibited a cyclic daily fluctuation due to solar radiation, which is the major heat source for nests. Clutch temperature was relatively stable and its daily amplitude was negatively correlated with clutch depth and size. Rainfall was the major source of clutch temperature decrease. Clutch and metabolic temperatures increased significantly during incubation. A small sample size failed to demonstrate a statistical relationship between length of incubation and mean clutch temperature. Proportion of embryos reaching complete development depended on maximum and minimum clutch temperature, maximum daily amplitude of clutch temperature and maximum decrease in clutch temperature on a period ≤4 day. Results confirmed a Female–Male–Female TSD pattern for C. acutus, with 31 and 32.5°C as possible pivotal temperatures. Population and hatchling sex ratios were male-biased and fate of crocodiles of Banco Chinchorro could depend on the magnitude of temperature increase in the future. [Copyright &y& Elsevier]

The Nile crocodile ( Crocodylus niloticus) is an ancient icon of both cultural and scientific interest. The species is emblematic of the great civilizations of the Nile River valley and serves as a model for international wildlife conservation. Despite its familiarity, a centuries-long dispute over the taxonomic status of the Nile crocodile remains unresolved. This dispute not only confounds our understanding of the origins and biogeography of the 'true crocodiles' of the crown genus Crocodylus, but also complicates conservation and management of this commercially valuable species. We have taken a total evidence approach involving phylogenetic analysis of mitochondrial and nuclear markers, as well as karyotype analysis of chromosome number and structure, to assess the monophyletic status of the Nile crocodile. Samples were collected from throughout Africa, covering all major bioregions. We also utilized specimens from museum collections, including mummified crocodiles from the ancient Egyptian temples at Thebes and the Grottes de Samoun, to reconstruct the genetic profiles of extirpated populations. Our analyses reveal a cryptic evolutionary lineage within the Nile crocodile that elucidates the biogeographic history of the genus and clarifies long-standing arguments over the species' taxonomic identity and conservation status. An examination of crocodile mummy haplotypes indicates that the cryptic lineage corresponds to an earlier description of C. suchus and suggests that both African Crocodylus lineages historically inhabited the Nile River. Recent survey efforts indicate that C. suchus is declining or extirpated throughout much of its distribution. Without proper recognition of this cryptic species, current sustainable use-based management policies for the Nile crocodile may do more harm than good. [ABSTRACT FROM AUTHOR]

Background: Commercial farming of Caiman crocodilus crocodilus has had an impact on the use of this species for meat consumption and the leather industry. Spectacled Caimans comprise part of the South American plains biodiversity. Misinterpretation of laboratory data is a risk owing to the limited hematologic and serum biochemical values available for this species. Objective: The aim of this study was to determine hematologic and serum biochemical values for wild Spectacled Caimans from the Venezuelan plains. Methods: Blood samples were collected form the caudal tail vein of 100 Spectacled Caimans (40 males and 60 females) from the plains located in the State of Apure. Values for RBC count, PCV, hemoglobin concentration, WBC absolute and differential counts, and thrombocyte counts were obtained using manual methods, and RBC indices were calculated. Serum biochemical analysis included measurement of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, and creatine kinase activities and concentrations of total protein and albumin. Comparisons between sexes were analyzed using the Mann-Whitney test. Results: Reference values for wild Spectacled Caimans were determined. Minor differences in hematologic values, particularly for RBC counts, were found compared with previously published values for this species. Serum biochemical values were similar to those available for other crocodilians. There were no significant differences between males and females. Conclusions: Minor differences between the values obtained for wild Spectacled Caimans and those previously published for this species may be related to differences in methodology and environmental conditions. Availability of hematologic and serum biochemical reference values will be useful for accurate diagnosis and management of disease in this species. [ABSTRACT FROM AUTHOR]

Paraoistosomum novaeguineae n. gen., n. sp. is described based on specimens from the kidneys of a New Guinea crocodile Crocodylus novaeguineae collected in Papua New Guinea. The body shape and the topology of most internal organs of the new species are strongly reminiscent of Oistosomum caduceus Odhner 1902, the sole member of Oistosomum, a genus of unclear phylogenetic relationships and systematic position described from the Nile crocodile in Sudan in 1902 and never reported since then. At the same time, the new species has a; number of significant differences from Oistosomum caduceus. Among them are much shorter intestinal ceca, a relatively larger ventral sucker, ovary anterolateral to ventral sucker (posterolateral in O. caduceus), vitellaria arranged in 2 clusters of loosely organized follicles at the level of ventral sucker (2 narrow long lateral fields in O. caduceus), much longer esophagus, and other characters. Most importantly, the new species has the genital pore situated at the anterior body end adjacent to the oral sucker, whereas O. caduceus has the genital pore in front of the ventral sucker. These dramatic differences suggest establishment of a new genus for the species from Papua New Guinea. The anatomy of P. novaeguineae n. gen., n. sp. suggests that these genera may not belong to the Plagiorchiidae, the current familial allocation of Oistosomum. Scarcity of material and lack of molecular data do not permit clarification of this problem at the present time. [ABSTRACT FROM AUTHOR]

Abstract: The phylogenetic relationships among extant species of Crocodylus (Crocodylia) have been inconsistently resolved by previous systematic studies. Here we used nearly complete mitochondrial (mt) genomes (∼16,200 base pairs) for all described Crocodylus species, eight of which are new to this study, to derive a generally well-supported phylogenetic hypothesis for the genus. Model-based analyses support monophyly of all Asian+Australian species and paraphyly of Crocodylus niloticus (Nile crocodile) with a monophyletic New World clade nested within this species. Wild-caught Nile crocodiles from eastern populations group robustly with the four New World species to the exclusion of Nile crocodiles from western populations, a result that is also favored by parsimony analyses and by various subpartitions of the overall mt dataset. The fossil record of Crocodylus extends back only to the Late Miocene, while the earliest fossils assigned to C. niloticus and to New World Crocodylus are Pliocene. Therefore, in combination with paleontological evidence, mt DNA trees imply a relatively recent migration of Crocodylus from Africa to the Americas, a voyage that would have covered hundreds of miles at sea. [Copyright &y& Elsevier]

Abstract: Crocodylus is the largest genus within the Order Crocodylia consisting of eleven species. This paper reports the complete mitochondrial genome sequences of three Crocodylus species, Crocodylus moreletii, Crocodylus johnstoni and Crocodylus palustris, and compares the newly obtained mitochondrial DNA sequences with other crocodilians, available in the public databases. The mitochondrial genomes of C. moreletii, C. johnstoni and C. palustris are 16,827bp, 16,851bp and 16,852bp in length, respectively. These mitochondrial genomes consist of 13 protein coding genes, two ribosomal RNA genes, 22 transfer RNA genes and a non-coding region. The mitochondrial genomes of all the Crocodylus species, studied herein show identical characteristics in terms of nucleotide composition and codon usage, suggestive of the existence of analogous evolutionary patterns within the genus, Crocodylus. The synonymous and non-synonymous substitution rates for all the protein coding genes of Crocodylus were observed in between 0.001 and 0.275 which reveal the prevalence of purifying selection in these genes. The phylogenetic analyses based on complete mitochondrial DNA data substantiate the previously established crocodilian phylogeny. This study provides a better understanding of the crocodilian mitochondrial genome and the data described herein will prove useful for future studies concerning crocodilian mitochondrial genome evolution. [Copyright &y& Elsevier]

The American crocodile ( Crocodylus acutus) is a large apex predator with an extensive but fragmented range. Crocodylus acutus suffered a population crash and was almost extirpated from Florida (USA) during the 1970s; however, in 2007 it was federally downlisted from endangered to threatened based on an increase of suitable habitat and a growing population. A genetic assessment of this population has not been performed even though foreign crocodiles have been released into Florida waters. Herein, we use mitochondrial and nuclear DNA markers to characterize relationships among American crocodiles along the southern coast of Florida and reference samples from other countries. We detected inter- and intra-specific hybridization and unexpected population structure attributed to human-mediated migration of crocodiles from Latin America and the Greater Antilles. Our results suggest that the population size of crocodiles actually native to Florida should be reevaluated, particularly in light of ongoing admixture in this population. We reemphasize the utility of genetic markers in conservation and management programs for endangered species; especially those that can hybridize with closely related congeners. The American crocodile in Florida has recovered owing to successful conservation initiatives, but a long-term management protocol that takes genetic data into account is still needed. [ABSTRACT FROM AUTHOR]

Abstract: The genus Crocodylus consists of 11 species including the largest living reptile, Crocodylus porosus. The current understanding of the intrageneric relationships between the members of the genus Crocodylus is sparse. Even though members of this genus have been included in many phylogenetic analyses, different molecular approaches have resulted in incongruent trees leaving the phylogenetic relationships among the members of Crocodylus unresolved inclusive of the placement of C. porosus. In this study, the complete mitochondrial genome sequences along with the partial mitochondrial gene sequences and a nuclear gene, C-mos were utilized to infer the intrageneric relationships among Crocodylus species with a special emphasis on the phylogenetic position of C. porosus. Four different phylogenetic methods, Neighbour Joining, Maximum Parsimony, Maximum Likelihood and Bayesian inference, were utilized to reconstruct the crocodilian phylogeny. The uncorrected pairwise distances computed in the study, show close proximity of C. porosus to C. siamensis and the tree topologies thus obtained, also consistently substantiated this relationship with a high statistical support. In addition, the relationship between C. acutus and C. intermedius was retained in all the analyses. The results of the current phylogenetic study support the well established intergeneric crocodilian phylogenetic relationships. Thus, this study proposes the sister relationship between C. porosus and C. siamensis and also suggests the close relationship of C. acutus to C. intermedius within the genus Crocodylus. [Copyright &y& Elsevier]

The complete mitochondrial (mt) genomes of two crocodilians: Crocodylus palustris and Crocodylus mindorensis, were sequenced in order to examine their gene and genome features. Additionally, we intended to increase the amount of molecular data suitable for phylogenetic analysis. Their gene orders conform to other crocodilians that have been sequenced, except the arrangement of two tRNA genes differ from other vertebrates, showing that the gene order of crocodilians is remarkably conserved. Phylogenetic analyses (maximum likelihood, Bayesian inference) based on the mt protein-coding genes at the nucleotide level were performed among crocodilians for which complete mt genomes were available. The results suggest that the gharial (Gavialis gangeticus) joins the false gharial (Tomistoma schlegelii) on a common branch, that constitutes a sister group to traditional Crocodylidae. In this report, Mecistops cataphractus is evidently most closely related to Osteolaemus tetraspis. They are isolated as sister taxon from the main clades in Crocodylus. Regarding Paleosuchus, it appears as sister group to Caiman within the Alligatoridae. In particular, relationships among species of Crocodylus (true crocodiles) are discussed. [ABSTRACT FROM AUTHOR]

An antibacterial compound from crocodile blood was partially purified and functionally characterised. The freshwater crocodile ( Crocodylus siamensis) plasma with antibacterial activity was partially purified by using a centrifugal concentrator and reverse phase high powered liquid chromatography, and designated as crocosin. Crocosin exhibits antibacterial activity toward Salmonella typhi and Staphylococcus aureus. Crocosin is thermostable and resistant to pronase digestion. The structure of crocosin analyzed by mass spectrometry contains repeating units of 94 and 136 m/z. Scanning electron microscopy indicates that crocosin probably penetrates progressively into cytoplasm space, perturbing and damaging bacterial membranes. Crocosin may provide an early defense mechanism toward bacterial infection in freshwater. [ABSTRACT FROM AUTHOR]

Revision of the two extinct Javanese crocodylian species Gavialis bengawanicusDubois, 1908, and Crocodylus ossifragusDubois, 1908, indicates that only the former is valid and that the latter is a junior subjective synonym of the extant C. siamensisSchneider, 1801. Gavialis bengawanicus is diagnosed by a relatively small number of maxillary and dentary teeth, a modest maxillary process developed into the lacrimal, a W-shaped maxillo-palatine suture, a planar skull table, occlusal pits present exclusively on the dentaries, and relatively small and subcircular supratemporal fossae at maturity. It is the best-known extinct Gavialis, and it probably represents the only valid extinct Gavialis species known outside the Indian subcontinent. Both crocodylians from Java have been found exclusively along with the Stegodon-Homo erectus fauna, which is considered to be largely the result of an Early Pleistocene dispersal from the Siwaliks Hills via the so-called Siva–Malayan route. It is not clear if the dispersal of Gavialis from the Indian subcontinent to Java necessarily required the crossing of salt water barriers, but the possible occurrence of Gavialis remains in Sulawesi and Woodlark, two islands located east of the Huxley and Wallace lines that were never connected to the mainland, can be explained by inferring a marine dispersal. According to the present knowledge of the past distribution of Gavialis, this genus originated in the Indo-Pakistani area in the early Miocene and during the Quaternary dispersed to the Sunda region, possibly reaching western-most Oceania. [ABSTRACT FROM AUTHOR]

Abstract: The results presented describe and compare the fatty acid composition and melting properties of captive, healthy wild, and pansteatitis-affected wild crocodiles (Crocodylus niloticus). Differences in fatty acid composition between intramuscular and adipose fat is noted in captive crocodiles, and the latter differs from wild crocodiles as a result of different diets. Adipose fat of healthy wild crocodiles differs minimally from diseased ones, respectively with 37.3±2.6% vs. 43.2±2.3% monounsaturated fatty acids, and 43.2±2.9% in dead crocodiles, while polyunsaturated fatty acids decrease from 27.3±1.9% to as low as 21.9±3.6% respectively. Of the unsaturated fatty acids 18:2n−6 decreased from 6.5±2.6% in unaffected crocodiles to 3.5±0.6% in highly affected and 3.2±0.4% in dead crocodiles, and 22:5n−3 from 2.8±0.6% to 1.8±0.3% and 2.2±0.3% respectively. The melting properties as determined by differential scanning calorimetry show that extracted adipose fat is a small degree softer in pansteatitis-affected tissue, specifically in the temperature range 7–36°C, and does not contribute to the hard texture noted for adipose fat tissue of pansteatitis-affected animals. A high moisture content of 51.0±19.7% of the fat tissue of pansteatitis-affected animals vs.17.1±8.0% of healthy ones, suggests that physiological changes due to interstitial inflammation may contribute to the hard texture. [Copyright &y& Elsevier]

Abstract: The six peculiar multicusped teeth described here were collected from sediments of the Upper Cretaceous of São José do Rio Preto Formation, near Ibirá (northeastern São Paulo, Brazil). Their bulbous crowns are slightly labio-lingual compressed, and bear a main plus two accessory cusps, which conceal a well developed cingulum. Wear facets are seen on the main and distal accessory cusps. Comparison to the known Crocodyliformes with multicusped teeth show that the new material is not referable to “protosuchians” or eusuchians, nor related to two unnamed forms from Morocco and “notosuchians” such as Uruguaysuchus, Chiamaerasuchus, and Simosuchus. On the other hand, possible affinities with Candidodon and Malawisuchus were maintained based on shared traits. This includes teeth with the main cusp and some accessory cusps arranged in more than one axis, a previously defined unambiguous apomorphy of the putative clade composed of Candidodon plus Malawisuchus. The term Candidodontidae can be applied to this group, and defined as all taxa closer to Candidodon itapecuruensis than to Notosuchus terrestris, Uruguaysuchus aznarezi, Comahuesuchus brachybuccalis, Sphagesaurus huenei, Baurusuchus pachecoi, and Crocodylus niloticus. [Copyright &y& Elsevier]

The article presents information on a study which conducted spotlight surveys and nest counts to evaluate the current status of American crocodile or Crocodylus (C.) acutus populations in Turneffe Atoll, Belize. Observations were made on 23 C. acutus along the survey route in May 2008 and eight crocodiles during late June-early July. It revealed that overall crocodile encounters were significantly lower compared to surveys conducted in 2002. The same goes with the number of nests which is indicative of a reduction in breeding females in the Turneffe Atoll crocodile population.

The population and conservation status of crocodiles throughout West and Central Africa is poorly known and the IUCN Crocodile Specialist Group's highest priority recommendations are country status surveys and examination of potential threats. This study presents survey data and a review of the conservation status of the Nile crocodile Crocodylus niloticus , slender-snouted crocodile Mecistops cataphractus and African dwarf crocodile Osteolaemus tetraspis at 67 sites throughout Ghana and Côte d'Ivoire. No crocodiles were sighted in 31.5% of surveys but, where encountered, densities averaged 0.90 crocodiles sighted km -1 . The most frequently encountered crocodile was C. niloticus (94% of sightings) with population structure highly biased to individuals < 1 year of age (41.4%). Only 14 M. cataphractus were observed. Local informants report that crocodiles were more common 10-20 years ago than at present. There is now little commercial harvest, which includes limited use in the bushmeat and traditional medicine markets, because of the crocodile's scarcity. Habitat encroachment and incidental bycatch in fishing devices appear to be the major threats. Actions needed to improve the conservation status of crocodile populations in both countries, and throughout the region, are discussed. [ABSTRACT FROM AUTHOR]

The crocodylian remains stored in the collection of the Provincial Museum Joanneum (Graz, Austria) are reviewed. Previous descriptions, geographical and stratigraphical provenance and collection history are discussed. The most important area from which these fossils come from - the Wies-Eibiswald coal-mining district - is briefly discussed. Preliminary taxonomical considerations concerning the type material of Enneodon ungeri PRANGNER, 1845, Diplocynodon steineri (HOFMANN, 1887a) and Diplocynodon styriacus (HOFMANN, 1887a) are provided. [ABSTRACT FROM AUTHOR]

Between 1995 and 1998 we studied the effects of water level, moon phase, and site on the number of caimans observed in spotlight surveys in the Mamirauá Sustainable Development Reserve, Brazilian Amazonia. Multiple linear regression analyses including water level of the Amazon River and the moon phase explained 91 and 73% of the variance in number of Melanosuchus niger seen in spotlight surveys in Lago Mamirauá and Cano Mamirauá, respectively, and 60 and 76%, respectively, of the variance in the number of Caiman crocodilus seen. Water level had a statistically significant and negative effect on the number of M. nigerand C. crocodilus seen. Moon phase had no significant effect on the number of C. crocodilus seen, but more M. nigerwere detected in Lago Mamirauá on nights with more moon light. The regression equations derived for Lago Mamirauá and Cano Mamirauá did not adequately predict the variation in numbers seen in 18 other water bodies in the Mamirauá Reserve. Analysis of covariance showed an interaction between water level and site on the numbers of M. niger and C. crocodUus observed in the spotlight surveys in these water bodies, indicating that the effect of water level depends on the site. In these analyses, moon phase did not have a significant effect on either species, and there was no interaction between moon phase and site. To monitor natural tendencies, or impacts (e.g., controlled commercial hunting), on caiman populations of Mamirauá Reserve, it will be necessary to undertake regular spotlight surveys in many water bodies of all types at a narrow range of water level to have confidence in the results. [ABSTRACT FROM AUTHOR]

Abstract: The ability to thermoregulate in reptilians is often through behavioural modification. We investigated body temperature (T b) patterns during winter in the amphibious Nile crocodile (Crocodylus niloticus) and its relationship to basking behaviour at the St. Lucia Crocodile Centre, St. Lucia, South Africa. It was found that crocodiles had no daily plateaus in T b but rather continuous oscillations in T b within a range of mean minimum T b 18.8–19.6°C to mean maximum T b 26.9–29.2°C. Crocodile T b increased during the day, usually after 10:00 irrespective of body size. Behavioural data showed that the crocodiles usually left the water to bask around 10:00. It is suggested that basking behaviour is important for elevating T b rather than attaining a preferred T b. The increased T b may allow them to perform optimally when they return to water. The basking occurrence has management implications as it suggests that the best time to conduct aerial censuses of the St. Lucia crocodiles is during winter after 10:00 when most of the individuals are basking and hence most easily seen. [Copyright &y& Elsevier]

Genus Crocodylus is considered to have originated in Africa during the Early Miocene but it is only in the Late Miocene that there are evidences of dispersal toward Europe, where tomistomines and the alligatoroid Diplocynodon were widespread since the Paleogene. Revision of the type material of Crocodylus bambolii Ristori, 1890, a Tortonian crocodylian from the renowned Oreopithecus localities in central Italy, excludes it from Diplocynodon. The morphology of the remains, combined with chronology and biogeography, confirms its identity as cf. Crocodylus. The validity of the species Crocodylus bambolii is however not supported by the available morphological characters so that a solid differential diagnosis cannot be realized. It is therefore here proposed to consider Crocodylus bambolii as a nomen dubium. The European Late Miocene distribution of short-snouted crocodylians sees only alligatoroids in western Europe and, curiously, only crocodylids in the Central Mediterranean area. The Tusco-Sardinian and the Apulo-Abruzzi paleobioprovinces, whose lands are nowadays part of the Italian peninsula, are apparently the only European areas inhabited by short-snouted crocodylids, which are at the same time among the last crocodylians of the continent. The isolated teeth from Fiume Santo and Scontrone, two localities of these palebioprovinces, are also not Diplocynodon-like, but further material is needed to identify their owners with confidence. [ABSTRACT FROM AUTHOR]

New material of a long-snouted dyrosaurid has been discovered in the Paleocene of Morocco. It consists of a well-preserved skull with embedded mandible and four dorsal vertebrae. The particularly elongate snout, proportionally the longest of all known dyrosaurids, allows precise identification of this material as Atlantosuchus coupatezi Buffetaut, 1979 a , and presentation of an emended diagnosis for this species previously known only from a mandibular symphysis. A phylogenetic analysis of the dyrosaurids indicates a close relationship between A. coupatezi and Rhabdognathus. It also confirms a previous hypothesis that Congosaurus is distinct from Hyposaurus. It is more closely related to Atlantosuchus than Hyposaurus. The analysis also allows palaeobiogeographic interpretations to be made. Dyrosaurids ranged from North Africa to other areas. They were rare during the Maastrichtian and endemic to each continent at this time. Competition with large marine reptiles, such as mosasaurs, limited their dispersal during the Late Cretaceous. The disappearance of these rivals during the ‘K-T crisis’ enabled their diversification and widespread dispersal during the Paleocene, with the same genera present on several continents. [ABSTRACT FROM AUTHOR]

Phylogenetic analysis indicates that Crocodylus robustus Grandidier & Vaillant, 1872 is more closely related to the living African dwarf crocodiles ( Osteolaemus) than to living Crocodylus. The type series cannot be identified, but the original description includes details consistent with known specimens that almost certainly pertain to the same species. It had a prominent triangular ‘horn’ on the posterolateral corner of each squamosal; near-exclusion of the nasals from the external naris; constricted supratemporal fenestral rims; a dorsoventrally deep snout; a constricted external mandibular fenestra in which the surangular–angular suture emerges from the posterior rather than posteroventral margin; and robust limb and limb girdle elements. It shares with Osteolaemus, and with several extinct crocodylids from the Neogene of Africa, a depressed surface of the pterygoid around the internal choana forming a choanal ‘neck’. It cannot be referred to Crocodylus and a new praenomen, Voay, is established for its reception. Voay persisted into the Holocene and may have been extant when humans first settled Madagascar 2000 years ago, when it may have been a casualty of a megafaunal extinction event on the island. This is consistent with molecular data that suggest comparatively recent dispersal of Crocodylus niloticus to Madagascar from mainland Africa. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 150, 835–863. [ABSTRACT FROM AUTHOR]