1,920 research outputs found
On ant-like Synemosyna Hentz, 1846 spiders from Bolivia, with indirect evidence for polymorphic mimicry complexes (Araneae: Salticidae: Simonellini)
Three species of Synemosyna Hentz, 1846 were recorded during a survey in five Bolivian forest ecoregions: S. aurantiaca (Mello-Leitão, 1917), S. myrmeciaeformis (Taczanowski, 1871) and S. nicaraguaensis Cutler, 1993. Synemosyna aurantiaca and S. nicaraguaensis are recorded for Bolivia for the first time and the previously unknown male of S. nicaraguaensis is described and illustrated. The habitus and the genitalia of the female of S. myrmeciaeformis are illustrated for the first time. Synemosyna aurantiaca occurs in semi-deciduous forests south of 18° S and S. myrmeciaeformis in the Bolivian Yungas forest and ecoregions of the Amazon biome north of 16° S. Synemosyna nicaraguaensis is possibly an Andean species that enters into the moist Isthmian forests of Central America. Several potential mimicry complexes with two broad patterns were observed: sex-specific polychromatic mimicry (S. nicaraguaensis), and transformational mimicry involving smaller orange and larger brown to dark-brown forms (S. aurantiaca and S. myrmeciaeformis).Fil: Perger, Robert. Colección Boliviana de Fauna; BoliviaFil: Rubio, Gonzalo Daniel. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Misiones. Estacion Experimental Agropecuaria Cerro Azul.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Haddad, Charles R.. University of the Free State; Sudáfric
A revision of the endemic South African spider genus Austrachelas, with its transfer to the Gallieniellidae (Arachnida: Araneae)
The endemic South African spider genus Austrachelas Lawrence, 1938 is revised. The type species, A. incertus Lawrence, 1938, and A. natalensis Lawrence, 1942, are redescribed, and their males described for the first time. Seven new species are described: A. bergi n. sp. (female only), A. kalaharinus n. sp. (male only), A. merwei n. sp. (both sexes), A. pondoensis n. sp. (both sexes), A. reavelli n. sp. (both sexes), A. sexoculata n. sp. (male only), and A. wassenaari n. sp. (both sexes). A cladistic analysis performed including Austrachelas and various species of the corinnid subfamilies Trachelinae, Castianeirinae, Corinninae and Phrurolithinae, and species from the Liocranidae, Gallieniellidae and Lamponidae, suggests that Austrachelas is currently misplaced. Its transfer to the Gallieniellidae is proposed.Fil: Haddad, Charles R.. University of the Free State; SudáfricaFil: Lyle, Robin. University of the Free State; SudáfricaFil: Bosselaers, Jan. Royal Museum for Central Africa; BélgicaFil: Ramirez, Martin Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin
Ground-dwelling spider assemblages in contrasting habitats in the central South African Grassland Biome
Background: Ground-dwelling spider assemblages in shrublands and cultivated pastures in the South African Grassland Biome have never been comprehensively studied.
Objectives: Epigeic spiders were collected in eight different habitats in the Amanzi Private Game Reserve in the Free State to determine assemblages of different vegetation types.
Methods: Three of the sampled habitats were contrasting low-lying shrublands; three were contrasting hill aspects (northern slope, southern slope and plateau) in the Buddleja saligna–Searsia burchellii–Olea europaea africana subcommunity; one habitat was cultivated Digitaria eriantha pastures, and the last habitat was an area in and around a freshwater dam. Spiders were sampled by pitfall trapping in early spring (Sept. 2012), mid-summer (Jan. 2013), mid-autumn (Apr. 2013) and mid-winter (July 2013).
Results: A total of 2982 adult spiders were collected, representing 129 species and 33 families. Ammoxenidae was the most abundant family (40.85%), followed by Gnaphosidae (21.26%), Zodariidae (10.80%) and Salticidae (10.26%). Gnaphosidae was the most species-rich family (24.81%), followed by Salticidae (13.18%), Lycosidae (11.63%) and Zodariidae (6.20%). Spider activity densities and species richness did not differ significantly between habitats, although significant seasonal fluctuations were detected. The three hill aspects and cultivated D. eriantha pastures had the most distinct assemblages, while those of the three low-lying shrublands and freshwater dam showed considerable overlap.
Conclusions: Our results indicate that the aspect of hills has a significant effect in shaping spider assemblages, while the vegetation composition of shrublands is not strongly influential. The unique spider assemblages of cultivated D. eriantha pastures can be attributed to the absence of woody plants.
Conservation implications: This was the first study to investigate ground-dwelling spider assemblages in shrublands and cultivated pastures in the South African Grassland Biome. Our study confirms that hill aspects, shrublands and pastures harbour very different spider faunas. When identifying land for potential expansion or establishment of protected areas, conservation planners should ensure that the greatest diversity of vegetation units are included to optimise the conservation of biodiversity
A new species of the spider genus Cangoderces (Araneae, Telemidae) from South Africa
A new species of the spider family Telemidae from South Africa, Cangoderces globosa sp. n., is diagnosed, described and illustrated. This is the second species of the family to be recorded from the country. Consistent with the habits of most Afrotropical telemids, C. globosa sp. n. was collected by sifting leaf litter in forests
Checklist of the spiders (Arachnida, Araneae) of the Table Mountain National Park, South Africa
The Table Mountain National Park (TMNP) is an iconic protected area in South Africa, renowned for the high levels of plant and animal species richness and endemism. An annotated species list of spiders presently known from the TMNP is provided. The checklist was compiled from data collected from the South African National Survey of Arachnida (SANSA) database. A total of 261 species from 50 families and 167 genera are presently protected in the park. The most species-rich families are the Salticidae (31 spp.), Thomisidae (26 spp.) and Araneidae (20 spp.), while 13 families are represented by singletons. The global distribution, endemicity and International Union for the Conservation of Nature (IUCN) Red List status of each species is provided.
Conservation implications: Seventy-seven per cent of the species have a wide distribution range and are of Least Concern (200 spp.), while 31 species are Data Deficient, four species were not evaluated, and 26 species of special concern are identified. Of these, 13 spp. are Rare, three each are Critically Rare and Endangered, six are Vulnerable and one is near threatened. The TMNP protects approximately 11.4% of the total South African spider fauna and it is the type locality for 31 species. Although the TMNP and Cape Peninsula more broadly is a hotspot of endemic species for various plant and animal taxa: a proportionally small proportion of the spider species are of significant conservation concern
Diversity of non-acarine arachnids of the Ophathe Game Reserve, South Africa : testing a rapid sampling protocol
As part of the second phase of the South African National Survey of Arachnida (SANSA),
field surveys were conducted in many degree-square grids throughout the country using a
standardised rapid sampling protocol. This study reports on the arachnid diversity of the
Ophathe Game Reserve (OGR) in northern KwaZulu-Natal, as found during a preliminary
survey in June 2007 (mid winter) and a SANSA field survey in October 2008 (mid spring) in
four representative habitats. The SANSA survey included seven sampling methods: pitfalls,
beating, sweep-netting, litter sifting, hand collecting, night collecting and Winkler traps. A total
of 282 species in six arachnid orders were collected during the two surveys, of which spiders
were the most species-rich order (268 species in 47 families). The SANSA survey yielded 966
adult arachnids, representing six orders and 197 species, with a further 67 species represented
only by immatures. Although adult arachnid abundance (n) differed considerably between
the four habitats (range: 156–321), adult species richness (Sobs) was less variable (range: 65–85).
These survey results are comparable with several longer-term surveys in the Savanna biome,
and indicate that the SANSA sampling protocol can yield an impressive diversity of arachnids
during a relatively short period of sampling, with a high level of coverage (> 0.8 for sites
and most sampling methods) and moderate levels of sample completion for adults (> 0.55
for all sites), despite logistical and temporal challenges. Additional repetitions of the SANSA
sampling protocol in other seasons will likely increase biodiversity knowledge of arachnids in
OGR considerably.
CONSERVATION IMPLICATIONS : The implementation of rapid sampling protocols in an atlas
project is essential to generate a large volume of species-level data. The SANSA protocol is an
efficient means for rapidly generating arachnid data, and in future will allow for an assessment
of diversity patterns in degree-square grids across South Africa.http://www.koedoe.co.zaam201
Spiders (Arachnida: Araneae) of the vegetation layer of the Mkambati Nature Reserve, Eastern Cape, South Africa
The Pondoland region of the Eastern Cape province, South Africa is very poorly studied with
regard to invertebrate diversity, particularly in the case of arachnids. Accordingly, and in
view of proposed infrastructural and mining developments in this ecologically sensitive area
of high plant endemism, baseline data are provided on spiders (Araneae) of the vegetation
layer (i.e. excluding the ground-dwelling fauna) of the Mkambati Nature Reserve (MNR).
Spiders were collected at 26 sites (six forest and 20 grassland sites) in the MNR over an
eight-day period, using sweep sampling and active searching of flowers in grassland and
tree beating in forests, as part of a broader biodiversity survey. Additional specimens were
collected with Malaise and pan traps. A total of 1275 specimens were sampled, representing
132 species (6.6% of the total number recorded in South Africa) in 103 genera and 29 families.
Theridiidae and Araneidae were the most diverse spider families in the reserve, represented
by 22 species each (16.7% of the total), followed by Thomisidae with 19 species (14.4%) and
Salticidae with 18 species (13.6%). Grassland and forest had distinct spider faunas, with only
24.2% of species being recorded from both biomes. The average number of species sampled
per site in grassland and forest was 26 species for both habitats, although values for the two
biomes are not directly comparable because different sampling methods were used. All 132
species are new records for the reserve, of which 20 were new records for the Eastern Cape
and at least eight spider species may be new to science. The spider diversity captured despite
temporal and methodological limits indicates that many additional species are likely to occur
in the reserve. CONSERVATION IMPLICATIONS: If the MNR is not adequately conserved at least five new species,
which may be confined to the area, would be at high risk of extinction and 15 other species
endemic to the Pondoland and KwaZulu-Natal region would have their risk of extinction
increased.The Earthwatch Institute, Eastern Cape Nature Conservation and the National Research Foundation through a grant to M.H.http://www.koedoe.co.zaab201
The future of the global food system
Although food prices in major world markets are at or near a historical low, there is increasing concern about food security—the ability of the world to provide healthy and environmentally sustainable diets for all its peoples. This article is an introduction to a collection of reviews whose authors were asked to explore the major drivers affecting the food system between now and 2050. A first set of papers explores the main factors affecting the demand for food (population growth, changes in consumption patterns, the effects on the food system of urbanization and the importance of understanding income distributions) with a second examining trends in future food supply (crops, livestock, fisheries and aquaculture, and ‘wild food’). A third set explores exogenous factors affecting the food system (climate change, competition for water, energy and land, and how agriculture depends on and provides ecosystem services), while the final set explores cross-cutting themes (food system economics, food wastage and links with health). Two of the clearest conclusions that emerge from the collected papers are that major advances in sustainable food production and availability can be achieved with the concerted application of current technologies (given sufficient political will), and the importance of investing in research sooner rather than later to enable the food system to cope with both known and unknown challenges in the coming decades
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