Hippopotamyrus ansorgii species complex in the Upper Zambezi River System with a description of a new species, H. szaboi (Mormyridae).

Zoologica Scripta, 33, 1–18.

Abstract:

Specimens referable to Hippopotamyrus ansorgii sampled from the Upper Zambezi River System within Caprivi (Namibia) represent a complex of three species, two of which coexist in the Upper Zambezi River, and a third that inhabits a nearby river, the Kwando, with which the Zambezi has been connected during periods of flooding. All three are indistinguishable in terms of their general appearance, but differ consistently in electric organ discharges (EOD), morphology, and molecular genetic characters. All phenotypes display a monopolar, head-positive EOD pulse with specific post- or prepotentials. For H. ansorgii from the Zambezi River (HaZ), pulse duration is less than 0.5 ms (down to 0.205 ms; N= 34); for the syntopic H. szaboi sp. n., it is greater than 0.6 ms (up to 1.8 ms at 10% peak amplitude; N= 19). The parapatric phenotype of H. ansorgii from the Kwando River (HaK) has pulses shorter than 0.215 ms (down to 0.105 ms; N = 36). All three members of the species complex may be distinguished from each other by 7−9 anatomical characters, analysed by manova. Based on 22 enzymes and proteins studied, the moderate to high Wright's fixation index and the significant (P < 0.05) allele differentiation between EOD phenotypes provide additional evidence for incipient speciation. Pairwise analyses of the three different phenotypes showed the two parapatric species of H. ansorgii grouped together, and distinguishable from individuals of H. szaboi. Analyses of the mitochondrial cytochrome b gene revealed that all specimens which were attributed to H. szaboi form a well-supported monophyletic basal clade (bootstrap support 73% or 82%). The genetic distances (uncorrected p distances) between H. szaboi and the two species of H. ansorgii are between 0.6% and 1.7%. Within the derived H. ansorgii clade some phylogeographical differentiation can be seen for fishes from the Zambezi and Kwando Rivers, but the respective groups are not consistent or supported by significant bootstrap values. The question of which of the two parapatric morphological and EOD phenotypes of H. ansorgii recognized in the present paper represents H. ansorgii (Boulenger, 1905) cannot be resolved at present because of the paucity and unclear origin of the historical type material.

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Donnerstag, 14 Juni 2018 21:47

KAMDEM TOHAM, A. et al. (eds. 2006)

KAMDEM-TOHAM, A., D’AMICO, J., OLSON, D., BLOM, A., TROWBRIDGE, L., BURGESS, N., THIEME, ., ABELL, R., CARROLL, R. W., GARTLAN, S., LANGRAND, O., MIKALA MUSSAVU, R-, O’HARA, D. & STRAND, H.

A Vision for Biodiversity Conservation in Central Africa: Biological Priorities for Conservation in the Guinean-Congolian Forest and Freshwater Region.

111 Seiten. World Wildlife Fund, Inc., Washington, DC.

 

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Lion status updates from five range countries in West and Central Africa.

Cat News Nr. 52: 34-39. ISSN 1027-2992.

Abstract:

The lion Panthera leo is listed as Vulnerable on the IUCN Red List of Threatened Species and the species’ current status raises increasing concern among lion specialists across its African range. The situation is particularly alarming in West and Central Africa, where as few as 1000-2850 lions might remain, and where it is considered regionally Endangered in West Africa. Here we present results from lion surveys conducted in 2006-2010, covering 12 Lion Conservation Units (LCUs) in West Africa and three LCUs in Central Africa. We were able to confirm lion presence in only two of the LCUs surveyed in West Africa, and in none of the LCUs surveyed in Central Africa. Our results raise the possibility that no resident lion populations exist in Congo, Côte d’Ivoire and Ghana.

 

henschel-biblio

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Downward trends in Ngorongoro Crater ungulate populations 1986-2006: Conservation concerns and the need for ecological research.

Biological Conservation 131: 106-120.

Abstract:

The concentration of over 25,000 ungulates inside Ngorongoro Crater on a 250 km2 patch of the African plains was a major reason for designating the Ngorongoro Conservation Area as a World Heritage Site in 1979. As one of East Africa’s premier tourist attractions, it is also a major source of foreign exchange for Tanzania. This paper reports the decline of populations of wildebeest, Thomson’s and Grant’s gazelles since the mid-1980s and the rise to dominance of the buffalo, the results of research carried out from 1996 to 2000 on the Crater ungulates, and discusses natural and anthropogenic factors that may be linked to the population changes.Samples comparing young:adult female ratios in Ngorongoro and Serengeti populations indicated higher survival rates of Crater wildebeest and zebra young, and lower survival rates of Thomson’s gazelle. The possibility that predation by lions and spotted hyenas was responsible for reductions in the ungulate populations is belied by corresponding declines in the number of predators.Further research in the Ngorongoro Conservation Area is urgently needed to increase understanding of this complex ecosystem and promote effective stewardship, not only of Ngorongoro Crater but of the Serengeti ecosystem, of which the NCA is an integral part, comprising an International Biosphere Reserve. Our recommendations include establishment of a scientific advisory board and a research center that would attract and accommodate Tanzanian and foreign scientists.

estes-biblio

06.03.2013 - 1'292

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Donnerstag, 14 Juni 2018 22:18

EKOBO, A. (2003)

GTZ Mount Cameroon Project, Buea in Collaboration With WWF Cameroon Coastal Forests Programme.

Final Report. GTZ.

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Mittwoch, 06 März 2013 22:13

EHRENBERG, C. G. (1828)

Naturgeschichtliche Reisen durch Nord-Afrika und West-Asien in den Jahren 1820 bis 1825 von Dr. W. F. Hemprich und Dr. C. G. Ehrenberg, Historischer Theil.

Mittler, Berlin 1828.

Kostenloses e-Book: https://books.google.ch/books/about/Naturgeschichtliche_reisen_durch_Nord_Af.html?id=3YooAAAAYAAJ&redir_esc=y

ehrenberg-biblio

Freigegeben in E
Donnerstag, 14 Juni 2018 14:06

BUTYNSKI, T. M. & KOSTER, S. H. (1994)

Distribution and conservation status of primates in Bioko island, Equatorial Guinea.

Biodiversity and Conservation 3 (9): 893-909, DOI: 10.1007/BF00129665.

Abstract:

Ten species of non-human primates are indigenous to Bioko; half of these are endangered and between five and eight are endemic subspecies. Recent data on their status and distribution have been lacking. In 1986, a ten-week survey of the island was carried out to determine the distribution and status of the primates and the natural vegetation, and to evaluate the effects of man on them. This paper presents the results of that survey, gives an update of conservation achievements since 1986, and highlights current concerns. Between 1974 and 1986 it is probable that numbers of all Bioko primates rose as a result of an increase in habitat and of reduced hunting. At the time of the survey there was considerably more natural, undisturbed, vegetation remaining in Bioko tran expected. Much of this vegetation occurs within two large blocks that are of outstanding importance to the conservation of species in tropical Africa, particularly of plants and primates.

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Primates in Gabon - current status and distribution

ORYX 26 (4):223-234. ISSN 0030-6053. DOI: http://dx.doi.org/10.1017/S0030605300023759

Abstract:

This paper examines the current status and distribution of primates in Gabon on the basis of data collected in the field between 1985 and 1988. There are at least 19 and possibly 21 species of primates definitely present in Gabon, making it one of the richest countries in the world for primates. Most of the species are still widespread and one, the sun-tailed guenon, is endemic. Hunting and habitat destruction are the main threats to the country's primates. The major problem at the moment is the opening up of previously inaccessible areas by logging companies and the Trans Gabon railway, which leads to an increase in hunting pressure. Several species are threatened; the mandrill/drill, the black colobus, and the sun-tailed guenon need special conservation measures. Suggestions for action are made and several new reserves have recently been proposed.

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Donnerstag, 14 Juni 2018 22:35

BEGALL, S. & BURDA, H. (2011)

Der Ansell-Graumull - ein Überlebenskünstler unter Tage.

Z. Kölner Zoo 54, Heft 2: 89-103.

Einleitung:

Der Ansell-Graumull (Fukomys anselli) ist ein etwa hamstergroßes, unterirdisch lebendes Nagetier, das zur Familie der Sandgräber (Bathyergidae) gehört. Zwei Merkmale charakterisieren alle Sandgräberarten: Sie sind hervorragend an die unterirdische Lebensweise angepasst und sie kommen endemisch nur in Afrika südlich der
Sahara vor. Fukomys ist die artenreichste Gattung innerhalb der Familie und Sambia gilt bezüglich der Artbildung
als so genannter hot spot. Der wohl bekannteste Vertreter der Sandgräber ist allerdings der Nacktmull (Heterocephalus glaber), da er zum einen durch die Nacktheit und zum anderen durch sein bemerkenswertes Sozialsystem, so genannte Eusozialität, immer wieder das Interesse weckt.

Nacktmulle leben in großen Familien, wobei sich in jeder Familie immer nur ein Weibchen mit einem oder wenigen Männchen paart, während sich die Nachkommen nicht fortpflanzen, dafür aber ihren Eltern bei der Aufzucht jüngerer Geschwister direkt oder indirekt helfen. Aber auch einige Vertreter der Gattung Fukomys gelten als eusozial. Wir geben hier einen Einblick in die Biologie des Ansell-Graumulls und einiger seiner Verwandten. Unsere Beobachtungen und Analysen beruhen auf nunmehr 25 Jahren Forschung an den Graumullen im Labor sowie etlichen Freilandforschungen in Sambia.

In unserem Essener Labor („Mullarium“) halten wir neben dem Ansell-Graumull auch die Schwesterart, den Kafue-Graumull (Fukomys kafuensis), den Riesengraumull (Fukomys mechowii) sowie den Silbermull (Heliophobius argenteocinereus).

 

begall-biblio

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© Peter Dollinger, Zoo Office Bern hyperworx