1 - 10 of 10
Number of results to display per page
Search Results
2. An update on the distribution and diversification of Rhabdomys sp. (Muridae, Rodentia)
- Creator:
- Ganem, Guila, Dufour, Claire Marie Soleil, Avenant, Nico L., Caminade, Pierre, Eiseb, Seth J., Tougard, Christelle, and Pillay, Neville
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- range limits, contact zones, tail length, Africa, and COI
- Language:
- English
- Description:
- During the last two decades, genotyping of African rodents has revealed important hidden diversity within morphologically cryptic genera, such as Rhabdomys. Although the distribution of Rhabdomys is known historically, its diversity has been revealed only recently, and information about the distribution range of its constituent taxa is limited. The present study contributes to clarifying the distribution of Rhabdomys taxa, primarily in southern Africa, and identifies gaps in our knowledge, by: 1) compiling the available information on its distribution; and 2) significantly increasing the number of geo-localised and genotyped specimens (n = 2428) as well as the localities (additional 48 localities) sampled. We present updated distribution maps, including the occurrence and composition of several contact zones. A long-term monitoring of three contact zones revealed their instability, and raises questions as to the role of demography, climate, and interspecific competition on species range limits. Finally, an analysis of external morphological traits suggests that tail length may be a reliable taxonomic trait to distinguish between mesic and arid taxa of Rhabdomys. Tail length variation in Rhabdomys and other rodents has been considered to be an adaptation to climatic (thermoregulation) and/or to habitat (climbing abilities) constraints, which has still to be confirmed in Rhabdomys.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Bat-infesting chiggers (Acariformes: Trombiculidae) of the Balearic Islands and new data on the genus Trisetica Traub et Evans, 1950
- Creator:
- Stekolnikov, Alexandr A. and Quetglas, Juan
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Chigger mites, Mediterranean, Spain, Africa, bat hosts, Pipistrellus kuhlii, and Plecotus austriacus
- Language:
- English
- Description:
- A sample of chigger mites from bat hosts collected in the Balearic Islands (Western Mediterranean Sea) is found to include two species. These are the first records of bat-infesting chiggers identified to species in Spain. Chiggers collected from Pipistrellus kuhlii (Kuhl) in Menorca are identified as Oudemansidium komareki (Daniel et Dusbábek, 1959); this species, which was known from Austria, Bulgaria, Romania, Slovakia, Moldova, Crimea, and Azerbaijan, is recorded for the first time in Spain. Chiggers collected from Plecotus austriacus (Fischer) in Formentera are identified as Trombicula knighti Radford, 1954, which was insufficiently described from a bat in Yemen and known only from its type locality. We transfer this species to the genus Trisetica Traub et Evans, 1950 and provide its re-description based on paratypes and the material from the Balearic Islands. The species Sasatrombicula (Rudnicula) balcanica Kolebinova, 1966 is synonymised with T. knighti. One species closely related to T. knighti, Trisetica aethiopica (Hirst, 1926), which was recorded in Ghana, Uganda, South Sudan, and Madagascar, is re-described on the basis of its syntype deposited in the Natural History Museum, London, UK. This specimen is designated as lectotype.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Camouflage in arid environments: the case of Sahara-Sahel desert rodents
- Creator:
- Nokelainen, Ossi, Sreelatha, Lekshmi B., Brito, José Carlos, Campos, João C., Scott-Samuel, Nicholas E., Valkonen, Janne K., and Boratyński, Zbyszek
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Africa, background matching, crypsis, predation, and protective colouration
- Language:
- English
- Description:
- Deserts and semi-deserts, such as the Sahara-Sahel region in North Africa, are exposed environments with restricted vegetation coverage. Due to limited physical surface structures, these open areas provide a promising ecosystem to understand selection for crypsis. Here, we review knowledge on camouflage adaptation in the Sahara-Sahel rodent community, which represents one of the best documented cases of phenotype-environment convergence comprising a marked taxonomic diversity. Through their evolutionary history, several rodent species from the Sahara-Sahel have repeatedly evolved an accurate background matching against visually-guided predators. Top-down selection by predators is therefore assumed to drive the evolution of a generalist, or compromise, camouflage strategy in these rodents. Spanning a large biogeographic extent and surviving repeated climatic shifts, the community faces extreme and heterogeneous selective pressures, allowing formulation of testable ecological hypotheses. Consequently, Sahara-Sahel rodents poses an exceptional system to investigate which adaptations facilitate species persistence in a mosaic of habitats undergoing climatic change. Studies of these widely distributed communities permits general conclusions about the processes driving adaptation and can give insights into how diversity evolves.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. Description of Tresuncinidactylus wilmienae gen. et sp. n. (Monogenea: Gyrodactylidae), from the gills of the bulldog, Marcusenius macrolepidotus (Peters) from Lake Kariba, Zimbabwe
- Creator:
- Přikrylová, Iva, Barson, Maxwell, and Shinn, Andrew P.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- fylogeneze, phylogeny, Afrika, Africa, 18S rDNA, Mormyridae, 2, and 59
- Language:
- English
- Description:
- The African continent has a rich diversity of fish and amphibians in its inland water systems that serve as hosts for monogeneans of seven genera of the Gyrodactylidae van Beneden et Hesse, 1832. In August 2011, eight gyrodactylid parasites were collected from the gills of two specimens of bulldog, Marcusenius macrolepidotus (Peters), from Lake Kariba, Zimbabwe. Morphometric evaluation and sequencing of 18S rDNA confirmed that the specimens represented a species of a new viviparous genus, Tresuncinidactylus wilmienae gen. et sp. n. The attachment apparatus consists of a single pair of large slender hamuli with prominently flattened roots that are connected by a simple, narrow dorsal bar. The ventral bar is small and possesses a thin lingulate membrane but no evident anterolateral processes. There are 16 marginal hooks of one morphological type, but of three different sizes, with large falculate sickles that are proportionaly equal in length to the length of their handles. The two largest pairs of marginal hooks are positioned closest to the opisthaptoral peduncle, the neighbouring two pairs of medium-sized marginal hook sickles are situated along the lateral margins of the opisthaptor. Four pairs of smallest marginal hooks are positioned along the posterior margin of the opisthaptor. The male copulatory organ consists of a muscular pouch armed with approximately 30 gracile spines. Phylogenetic analyses of partial sequences of the 18S rDNA using Maximum Likelihood and Bayesian Inference placed the new genus within the lineage of solely African genera and suggests Afrogyrodactylus Paperna, 1968, Citharodactylus Přikrylová, Shinn et Paladini, 2017 and Mormyrogyrodactylus Luus-Powell, Mashego et Khalil, 2003 as genera most closely related to the new genus., Iva Přikrylová, Maxwell Barson, Andrew P. Shinn., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. Genetic diversity and origins of invasive black rats (Rattus rattus) in Benin, West Africa
- Creator:
- Etougbétché, Jonas , Houémènou, Gualbert , Dossou, Henri-Joël, Badou, Sylvestre , Gauthier, Philippe , Youssao Abdou Karim, Issaka , Nicolas, Violaine , and Dobigny, Gauthier
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- phylogeography, invasive species, cytochrome b, haplotype, polymorphism, and Africa
- Language:
- English
- Description:
- Black rats (Rattus rattus) are native to the Indian subcontinent but have now colonized most continents and islands following human movements and international trade. They are involved in the circulation and transmission to humans of many zoonotic agents as well as in massive damage to food stocks and native biodiversity in the regions they have settled. This study investigates the genetic diversity and possible origins of black rats from Benin, West Africa. We sequenced the complete mitochondrial cytochrome b gene in 90 individuals from nine localities in Benin. These sequences were subsequently compared to 390 other cytochrome b haplotypes from individuals from various European, Asian, American and African localities. Nucleotide polymorphism analysis, haplotype network and maximum likelihood phylogenetic tree reconstructions showed low mitochondrial diversity in black rats from Benin. Our results also suggest at least two distinct introduction events: one introduction probably occurred during the spice trade (15th-17th century) through the Indies Road connecting Europe to Asia. Other introduction events could have occurred more recently following the intensification of globalized trade from the eighteenth century, and onwards.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Morphological and molecular description of Allocreadium apokryfi sp. n. (Digenea: Allocreadiidae) from native Labeobarbus aeneus (Cyprinidae) in South Africa, including notes on its biology, evolutionary history and an updated key of African Allocreadium
- Creator:
- Dos Santos, Quinton M., Gilbert, Beric M., Avenant-Oldewage, Annemariè, and Dumbo, José C.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Smallmouth yellowfish, endoparasitic helminths, Trematoda, Africa, 28S rDNA, 18S rDNA, SEM, and taxonomic key
- Language:
- English
- Description:
- Adult trematodes of Allocreadium Looss, 1900 (Digenea) infect the intestine of mostly freshwater fishes in Asia, Europe, Africa and the Americas. During routine parasitological surveys in the Vaal River system, adult trematodes were collected from the intestine of smallmouth yellowfish, Labeobarbus aeneus (Burchell). The trematodes were confirmed to represent a member of Allocreadium and did not match any existing taxon. Therefore, they are described as a new species, Allocreadium apokryfi sp. n. The morphology of the new species most closely resembles that of Allocreadium aswanense El-Naffar, Saoud et Hassan, 1984, but it differs from it by having a bipartite internal seminal vesicle, wider eggs, a shorter intertesticular distance, an intestinal bifurcation at the ventral sucker level, a ventral sucker that is larger than the oral sucker, and a genital pore near the intestinal bifurcation or the ventral sucker. The surface topology of the new species is notably different from that of other allocreadiids. Papillae were observed in the ventral sucker and surrounding both ventral and oral suckers, but the number and arrangement of the latter were not consistent among specimens. The protruding cirrus of A. apokryfi sp. n. was described using SEM and is the first such observation for the genus. Genetic characterisation showed that the new species was clearly distinct from other Allocreadium spp. using both 18S (nucleotide difference 1.3-9.1%) and 28S (4.7-6.5%) rDNA, forming a well-supported clade in Allocreadium. The presence of A. apokryfi sp. n. in a well-studied river is unexpected, and considering the diet of its host and the scarcity of Allocreadium in Africa, the possible biology of this species is discussed herein.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. On the role of (and threat to) natural history museums in mammal conservation: an African small mammal perspective
- Creator:
- Ferguson, Adam W.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- IUCN Red List, voucher specimen, Africa, next-generation (holistic) collecting, and research ethics
- Language:
- English
- Description:
- The global environment is faced with growing threats from anthropogenic disturbance, propelling the Earth into a 6th mass extinction. For the world's mammals, this is reflected in the fact that 25% of species are threatened with some risk of extinction. During this time of species loss and environmental alteration, the world's natural history museums (NHMs) are uniquely poised to provide novel insight into many aspects of conservation. This review seeks to provide evidence of the importance of NHMs to mammal conservation, how arguments against continued collecting of physical voucher specimens is counterproductive to these efforts, and to identify additional threats to collecting with a particular focus on small mammals across Africa. NHMs contribute unique data for assessing mammal species conservation status through the International Union for Conservation of Nature's (IUCN) Red List of Threatened species. However, NHMs' contributions to mammal conservation go well beyond supporting the IUCN Red List, with studies addressing topics such as human impacts, climate change, genetic diversity, disease, physiology, and biodiversity education. Increasing and diverse challenges, both domestic and international, highlight the growing threats facing NHMs, especially in regards to the issue of lethally sampling individuals for the purpose of creating voucher specimens. Such arguments are counterproductive to conservation efforts and tend to reflect the moral opposition of individual researchers than a true threat to conservation. The need for continued collecting of holistic specimens of all taxa across space and time could not be more urgent, especially for underexplored biodiversity hotspots facing extreme threats such as the Afrotropics.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Some nematodes, including two new species, from freshwater fishes in the Sudan and Ethiopia
- Creator:
- František Moravec and Tomáš Scholz
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitičtí červi, helminth parasites, Afrika, Africa, taxonomy, new taxa, Osteichthyes, 2, and 59
- Language:
- English
- Description:
- Fourteen species (twelve adult and two larval) of nematodes belonging to the Ascaridoidea, Camallanoidea, Cosmocercoidea, Habronematoidea, Oxyuroidea, Seuratoidea and Trichinelloidea were collected from fishes in the Sudan (River Nile and Atbara Dam Lake), whereas only four species (one adult and three larval) of the Ascaridoidea, Camallanoidea, Dioctophymatoidea and Trichinelloideafrom fishes in Ethiopia (Lake Tana). The Sudanese material also contained two previously unknown species, Cucullanus mormyri sp. n. from Mormyrus caschive Linnaeus (type host), Mormyrus sp. and Marcusenius cyprinoides (Linnaeus) (all Mormyridae), and Procamallanus (Spirocamallanus) pseudospiralis sp. n. from Synodontis schall (Bloch et Schneider) (type host), S. frontosus Vaillant and S. nigrita Valenciennes (all Mochokidae), which are described based on light and scanning electron microscopical studies. Cucullanus baylisi Campana-Rouget, 1961, a little-known parasite of Synodontis spp., is redescribed in detail. A key to Procamallanus (Spirocamallanus) spp. from African inland fishes is provided. Falcaustra guiersi Vassiliadès, 1973 is considered a junior synonym of F. hexapapillata (Khalil, 1962). The findings represent several new host and geographical records. Cucullanus baylisi Lakshmi, 2000 (= a homonym to C. baylisi Campana-Rouget, 1961) is re-named as C. dubius nom. n. and is considered a species inquirenda., František Moravec, Tomáš Scholz., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Studies on ascaridid, oxyurid and enoplid nematodes (Nematoda) from fishes of the Okavango River, Botswana
- Creator:
- František Moravec and Van As, Liesl L
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitičtí červi, sladkovodní ryby, helminth parasites, freshwater fishes, Afrika, Africa, taxonomy, new species, Cucullanus, Cithariniella, Synodontisia, Galeiceps, 2, and 59
- Language:
- English
- Description:
- a1_Based on light and scanning electron microscopical studies, eight species (five adult and three larval) of nematodes belonging to the Ascaridida, Oxyurida and Enoplida were collected from fishes of the Okavango River, Botswana, namely Falcaustra similis Moravec et Van As, 2004, Atractidae gen. sp. (only female) (both Cosmocercoidea), Cucullanus sp. (only female) (Seuratoidea), Cithariniella longicaudata sp. n., Synodontisia annulata sp. n. (both Oxyuroidea), Contracaecum sp. third-stage larvae, third-stage larvae of Galeiceps sp. (both Ascaridoidea) and Eustrongylides sp. fourth-stage larvae (Dioctophymatoidea). The new species Citharinella longicaudata (type host Schilbe intermedius Rüppel) is mainly characterised by the shape and size of cephalic papillae and the spicule 108 µm long, and Synodontisia annulata (type host S. intermedius) by the shape of cephalic papillae, body length of gravid females (4.88-5.33 mm) and a short spicule (66 µm long). The female specimen of Cucullanus sp. from Tilapia sparmanni Smith markedly differs from congeners parasitising inland fishes in Africa by the elongate pseudobuccal capsule and by the excretory pore far posterior to the oesophago-intestinal junction; apparently, it belongs to an undescribed species. Galeiceps larvae parasitising fishes are described for the first time. Cithariniella gonzalezi Van Waerebeke, Chabaud, Bain et Georges, 1988 is considered a junior synonym of C. khalili Petter, Vassiliadès et Troncy, 1972, and the previous records of Cithariniella citharini Khalil, 1964 from Synodontis spp. in Egypt concern, in fact, Cithariniella khalili Petter, Vassiliadès et Troncy, 1972., a2_The specimens of Cithariniella reported by Koubková et al. (2010) from Paradistichodus dimidiatus (Pellegrin) in Senegal and misidentified as C. gonzalesi Van Waerebeke, Chabaud, Bain et Georges, 1988 are considered to represent a new species, C. koubkovae sp. n.; this is established by reference to the description and drawings provided by Koubková et al. (2010)., František Moravec, Liesl L. Van As., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public