Nucras scalaris LAURENT, 1964 | |
Nucras scalaris LAURENT, 1964
Baptista, N.L. & Tolley, K.A. & Bluhm, M. & Finckh, M. & Branch, W.R. (2020) - Rediscovery, range extension, habitat and phylogenetic relation of the endemic Scaled Sandveld Lizard Nucras scalaris Laurent, 1964 (Sauria: Lacertidae) in the central Angolan plateau - African Journal of Herpetology
The Scaled Sandveld Lizard Nucras scalaris Laurent, 1964 is a poorly known lacertid endemic to north-eastern Angola and is only known from the type series collected more than half a century ago. The original description provided a comprehensive morphological description, but there was a lack of information regarding its evolutionary relationships and habitat associations. A recent discovery of N. scalaris from Cusseque, Bié Province, on the central Angolan plateau provided the opportunity to address some knowledge gaps of this species. A phylogenetic analysis confirmed its distinctiveness at the species level. Despite a limited dataset, the analysis suggests that N. scalaris is sister to N. broadleyi rather than N. lalandii, the latter having been assumed to be the sister species, because of morphological similarity between them. The new record of N. scalaris represents a range extension of more than 350 km to the southwest and extends the elevation range to 1570 m above sea level, compared to previous known localities at about 1 300 m above sea level (Alto Cuílo and Alto Chicapa, in Lunda Sul Province). The specimen also provides new information on live coloration, as well as the habitat association of grassy shrubland that is dominated by geoxylic suffrutices (the so-called ‘underground forests’) characteristic of the Angolan Miombo Woodlands. This new information raises the question whether poor survey data have led to an under-estimation of faunal diversity in this peculiar and overlooked vegetation type, and reinforces the need for further surveys which could highlight the importance of this habitat.
Bischoff, W. (1996) - Übersicht der Arten und Unterarten der Familie Lacertidae. 4. Nachtrag. - Die Eidechse, Bonn/Bremen, 7 (18): 25-29.
Bischoff, W. (1998) - Übersicht der Arten und Unterarten der Familie Lacertidae. 5. Nachtrag. - Die Eidechse, Bonn, 9 (3): 91-99.
Branch, B. (1988) - Field guide to snakes and other reptiles of southern Africa. - Struik Publishers, Cape Town. 328 pp.
Branch, W.R. & Vaz Pinto, P. & Baptista, N. & Conradie, W. (2019) - The Reptiles of Angola: History, Diversity, Endemism and Hotspots. - In: Huntley B., Russo V., Lages F., Ferrand N. (eds.) Biodiversity of Angola: 283-334.
This review summarises the current status of our knowledge of Angolan reptile diversity, and places it into a historical context of understanding and growth. It is compared and contrasted with known diversity in adjacent regions to allow insight into taxonomic status and biogeographic patterns. Over 67% of Angolan reptiles were described by the end of the nineteenth century. Studies stagnated dur- ing the twentieth century but have increased in the last decade. At least 278 reptiles are currently known, but numerous new discoveries have been made during recent surveys, and many novelties await description. Although lizard and snake diversity is currently almost equal, most new discoveries occur in lizards, particularly geckos and lacertids. Poorly known Angolan reptiles and others from adjacent regions that may occur in the country are highlighted. Most endemic Angolan reptiles are lizards and are associated with the escarpment and southwest arid region. Identification of reptile diversity hotspots are resolving but require targeted surveys for their delimitation and to enable protection. These include the Kaokoveld Centre of Endemism, Angolan Escarpment and the Congo forests of the north. The fauna of Angola remains poorly known and under-appreciated, but it is already evident that it forms an important centre of African reptile diversity and endemism.
Ceriaco, L.M.P. & Marques, M.P. & André, I. & Afonso, E. & Blackburn, D.C. & Bauer, A.M. (2020) - Illustrated type catalogue of the “Lost” herpetological collections of Museu Dodundo, Angola. - Bull. Mus. Comp. Zool., 162 (7): 379–440.
The herpetological collections of the Museu do Dundo in Lunda Norte Province, northeast Angola, are among the most important in southern Africa and represent one of the largest collections of Angolan amphibians and reptiles in the world. The collection comprises more than 2,750 preserved specimens, including type specimens of taxa described by Raymond F. Laurent during the 1950s and 1960s,when he was affiliated with the Musee royal del’Afrique centrale (RMCA) in Tervuren, Belgium, and the Museum of Comparative Zoology (MCZ) at Harvard University, Cambridge, Massachusetts, where portions of these type series were also deposited. We provide details for all type specimens and summarize the history and taxonomy for each species represented in the type collection. The collections contain type specimens of 28 amphibian and reptile species, including seven snakes: Typhlops praeocularis lundensis, Dispholidus typus punctatus, Lycodonomorphus subtaeniatus, Lycophidion hellmichi, Gonionotophis brussauxi prigoginei, Prosymna ambıgua brevis, and Elapsoidea decosteri huilensis; 13 lizards: Rhoptropus boultoni montanus, Rhoptropus taeniostictus, Hemidactylus nzingae, Lygodactylus tchokwe, Cordylus vittifer machadoi, Chamaesaura anguina oligopholis, Gerrhosaurus bulsi, Nucras scalaris, Ichnotropis bivittata pallida, Mabuya bayonii huilensis, Mabuya ivensii septemlineata, Trachylepis raymondlaurenti, and Eumecia anchietae major; one amphisbaenian: Monopeltis vanderysti vilhenai; and seven frogs: Hyperolius machadoi,Hyperolius marmoratus alborufus, Hyperolius vilhenai, Ptychadena grandisonae, Ptychadena loveridgei, Ptychadena perplicata, and Ptychadena upembae machadoi. The typespecimens of the snake Xenocalamus bicolor machadoiwere not found in the collections. A brief history of the museum and remarks on the overall herpetological collections are also provided. We also note additional information about the related type material of these taxa at the MCZ.
Laurent, R.F. (1964) - Description of Nucras scalaris. - In: Reptiles et batraciens de l`Angola (troisième note). Companhia de Diamantes de Angola (Diamang), Serviços Culturais, Museu do Dundo (Angola), No. 67, 165 pp.
Lewin, A. & Feldman, A. & Bauer, A.M. & Belmaker, J. & Broadley, D.G. & Chirio, L. & Itescu, Y. & LeBreton, M. & Maza, E. & Meirte, D. & Nagy, Z.T. & Novosolov, M. & Roll, U. & Tallowin, O. & Trape, J.-F. & Vidan, E. & Meiri, S. (2016) - Patterns of species richness, endemism and environmental gradients of African reptiles. - Journal of Biogeography, 43 (12): 2380-2390.
Aim To map and assess the richness patterns of reptiles (and included groups: amphisbaenians, crocodiles, lizards, snakes and turtles) in Africa, quantify the overlap in species richness of reptiles (and included groups) with the other terrestrial vertebrate classes, investigate the environmental correlates underlying these patterns, and evaluate the role of range size on richness patterns. Location Africa. Methods We assembled a data set of distributions of all African reptile species. We tested the spatial congruence of reptile richness with that of amphibians, birds and mammals. We further tested the relative importance of temperature, precipitation, elevation range and net primary productivity for species richness over two spatial scales (ecoregions and 1° grids). We arranged reptile and vertebrate groups into range-size quartiles in order to evaluate the role of range size in producing richness patterns. Results Reptile, amphibian, bird and mammal richness are largely congruent (r = 0.79–0.86) and respond similarly to environmental variables (mainly productivity and precipitation). Ecoregion size accounts for more variation in the richness of reptiles than in that of other groups. Lizard distributions are distinct with several areas of high species richness where other vertebrate groups (including snakes) are species-poor, especially in arid ecoregions. Habitat heterogeneity is the best predictor of narrow-ranging species, but remains relatively important in explaining lizard richness even for species with large range sizes. Main conclusions Reptile richness varies with similar environmental variables as the other vertebrates in Africa, reflecting the disproportionate influence of snakes on reptile richness, a result of their large ranges. Richness gradients of narrow-ranged vertebrates differ from those of widespread taxa, which may demonstrate different centres of endemism for reptile subclades in Africa. Lizard richness varies mostly with habitat heterogeneity independent of range size, which suggests that the difference in response of lizards is due to their ecological characteristics. These results, over two spatial scales and multiple range-size quartiles, allow us to reliably interpret the influence of environmental variables on patterns of reptile richness and congruency.
Marques, M.P. & Ceríaco, L.M.P. & Blackburn, D.C. & Bauer, A.M. (2018) - Diversity and distribution of the amphibians and terrestrial reptiles of Angola: Atlas of historical and bibliographic records (1840-2017). - Proceedings of the California Academy of Sciences, Series 4, 65, Supplement II: 1-501.
The present work constitutes an historical atlas of all known bibliographic records of amphib- ians and reptiles of Angola. It is the first attempt to compile in a single document all the records scattered through hundreds of publications, published from the first half of the nineteenth century to the present day, and provide a critical taxonomic revision of the herpetofauna of the country. An introductory text discusses the Angolan socio-political and physiographic landscape, the history of herpetological research in the country, and the diversity, distribution and endemism of Angolan her- petofauna. It also provides a summary of the conservation concerns surrounding the herpetological fauna. For each taxon noted in the literature we provide a detailed taxonomic account, including data on the original description, its IUCN assessment status, global distribution, georeferenced records for each known occurrence in Angola (accompanied by a point locality map), and taxo- nomic and distributional notes. A synoptic list of all documented Angolan amphibian and reptile species is provided as are lists of taxa previously erroneously assigned to the Angolan fauna. We recognize 117 species of frogs and 278 species of reptiles as occurring in Angola, although many of these represent species complexes or are currently recognized under names of convenience pending taxonomic evaluation. In one instance we provide a replacement name, Trachylepis monardi nom. nov., to deal with an instance of secondary homonymy. The Atlas is intended to be a working reference for both current research and conservation planning, as well as a catalyst for future work.The interest shown by specialists in the study of Angolan specimens dates back more than one hundred years. Since the nineteenth century, books and papers have been published on the topic as the result of these investigations. The first major bibliographic reference about the Angolan herpetofauna, Herpétologie d’Angola et du Congo by José Vicente Barbosa du Bocage, dates from 1895. Many researchers and publications followed, greatly enriching the scientific bibliography on the topic. However, the scattered nature of the published works, as well as the dearth of available specimens from earlier times, has made it difficult for researchers, scholars or curious amateurs to access to this information. Because of these difficulties, and to facilitate the access to available data on the Angolan herpetofauna, the Ministry of Environment, through its National Institute of Biodiversity and Conservation Areas, decided to present, in a single volume, all the available scientific records published so far on the diversity of amphibians and reptiles. Such a task, which has its basis in the National Strategy and Action Plan for Biodiversity and Conservation Areas of Angola, was dependent upon the helpful collaboration of important international partners. The present Atlas will be of inestimable assistance to the study of the Natural History of Ango- la, not only because of its standardized taxonomic and geographical accounts with distribution maps for all of the amphibians and reptiles known in Angola, but also because of its competent approach to the physiography, climate, biomes, historical herpetological research in Angola, conservation, and other topics. The thoughtful way the book is arranged, with straightforward text, clear tables and interesting figures, makes it easy for even laymen to read and understand. At 501 pages long, profusely documented and richly illustrated, this Atlas provides a grand guided tour through the diversity of the Angolan herpetofauna, from the most remote and spectac- ular places of the country. Through mountains and escarpments, plains and valleys, savannas and dense forests, rivers and streams, lakes and lagoons, this work encompasses the entire country, aking us on an enlightening tour of knowledge. The methodical labor and persistence of the specialists who produced the present work, ensure that it not only contributes to scientific history, through its compilation of research already completed, but also suggests future directions for researchers and scholars devoted to the topic. Further, this substantial volume will also inform the national authorities with respect to environ- ment protection and conservation policies. Given all this, one can see that the present work, reflecting the contributions of the men and women who created it, is destined to become a standard reference to the scientific literature of the country, especially in regard to this part of its fauna. The quality of the scientific information poured into the following pages certainly qualifies the authors of this accurate work as leading herpetologists and places them among the important researchers to have served Angola in the course of its scientific history.
Meer, M.H. van der & Whiting, M.J. & Branch, W.R. (2010) - Ecology of Southern African Sandveld Lizards (Lacertidae, Nucras). - Copeia, 2010 (4): 568-577.
Sandveld lizards (genus Nucras) are widespread in southern Africa, but are generally secretive and poorly known. We examined 385 preserved specimens from five species of Nucras collected over a broad time span (104 years) and a geographic area covering most of South Africa and Swaziland. We had three main objectives: to test for sexual size dimorphism, to quantify male and female reproductive cycles, and to determine diet. In addition, we examined the importance of scorpions in the diet of Nucras based on previous studies reporting an unusually high incidence of scorpions in the diet of Kalahari N. tessellata. Males of all species except N. lalandii had significantly larger heads than females of the same body size, although females had significantly greater snout–vent length than males in three of the five species examined. The general reproductive pattern was for females to contain vitellogenic eggs during late spring and early summer. No females simultaneously contained oviductal and vitellogenic eggs, which suggests that females produce only one clutch per season. Clutch size was unrelated to female body size in all species examined. Female follicle volume generally coincided with male testicular volume, indicating for the most part synchronized reproductive cycles between the sexes. Testis volume was generally highest during spring–early summer, with only N. holubi showing a second peak in autumn. We recorded 15 arthropod orders in the diet of Nucras. All species feed on invertebrates, primarily insects, and, to a lesser degree, spiders and centipedes. Termites, grasshoppers, and beetles both numerically and volumetrically dominated their diet. We found no evidence that scorpions form a major part of the diet of any of these five species of Nucras, including N. tessellata from biomes outside the Kalahari Desert.
Meiri, S. (2008) - Evolution and ecology of lizard body sizes. - Global Ecology and Biogeography, 17 (6): 724-734.
Aim Body size is instrumental in influencing animal physiology, morphology, ecology and evolution, as well as extinction risk. I examine several hypotheses regarding the influence of body size on lizard evolution and extinction risk, assessing whether body size influences, or is influenced by, species richness, herbivory, island dwelling and extinction risk. Location World-wide. Methods I used literature data and measurements of museum and live specimens to estimate lizard body size distributions. Results I obtained body size data for 99% of the world`s lizard species. The body size–frequency distribution is highly modal and right skewed and similar distributions characterize most lizard families and lizard assemblages across biogeographical realms. There is a strong negative correlation between mean body size within families and species richness. Herbivorous lizards are larger than omnivorous and carnivorous ones, and aquatic lizards are larger than non-aquatic species. Diurnal activity is associated with small body size. Insular lizards tend towards both extremes of the size spectrum. Extinction risk increases with body size of species for which risk has been assessed. Main conclusions Small size seems to promote fast diversification of disparate body plans. The absence of mammalian predators allows insular lizards to attain larger body sizes by means of release from predation and allows them to evolve into the top predator niche. Island living also promotes a high frequency of herbivory, which is also associated with large size. Aquatic and nocturnal lizards probably evolve large size because of thermal constraints. The association between large size and high extinction risk, however, probably reflects a bias in the species in which risk has been studied.