A review of the Afrotropical tracheline sac spiders (Araneae: Corinnidae), with revisions of three genera

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Date
2008-05
Authors
Lyle, Robin
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Publisher
University of the Free State
Abstract
English: The sac spider subfamily Trachelinae (Araneae: Corinnidae) is currently represented in the Afrotropical Region by eight genera, namely Austrachelas Lawrence, 1938, Brachyphaea Simon, 1895, Cetonana Strand, 1929, Paccius Simon, 1897, Pronophaea Simon, 1897, Spinotrachelas Haddad, 2006, Thysanina Simon, 1910 and Trachelas L. Koch, 1872. The genera Brachyphaea and Pronophaea are misplaced, and most likely belong to the Corinninae, while Austrachelas is probably a gallieniellid. Numerous revisions have been done on New World and South-East Asian trachelines, but little work has been carried out on the fauna of the Afrotropical Region. In this dissertation a review of the literature pertaining to Afrotropical tracheline taxonomy, as well as the ecology, biology and medical importance of tracheline sac spiders, is given. A diagnosis for the five valid genera is given, together with a key to the genera. Three genera, namely Cetonana, Thysanina and Trachelas, were revised in the Afrotropical Region, with redescriptions of described species and descriptions of 58 new species. Additional notes on their biology and distribution were given, where possible. Specimens from 19 collections were examined, with measurements and genitalic drawings done for each species. In the genus Cetonana, Cetonana coenosa (Simon, 1897) and C. martini (Simon, 1897) were redescribed, and C. curvipes (Tucker, 1920), C. tridentata (Lessert, 1923) and C. simoni (Lawrence, 1942) were proposed as junior synonyms of C. martini. Ten new species were described. The type specimen of C. aculifera (Strand, 1916) from Madagascar could not be traced and is presumed destroyed, and therefore this species is considered nomen dubium. Within the monotypic genus Thysanina, the type species T. serica Simon, 1910 was redescribed and five new species were described from the Afrotropical Region (Lyle & Haddad, 2006). The genus Trachelas, with a cosmopolitan distribution, was only revised for the Afrotropical mainland. The species T. chubbi Lessert, 1921, T. pusillus Lessert, 1923, T. roeweri Lawrence, 1923, T. schenkeli Lessert, 1923 and T. sylvae Caporiacco, 1949 were redescribed. Forty-eight new species were described from various localities throughout the region. Trachelas scopulifer Simon, 1896 was redescribed, and its transfer to the genus Thysanina is proposed. The juvenile type specimen of T. punctatus Simon, 1886 could not be traced and is presumed lost, and this species is therefore considered nomen dubium. The results of this dissertation have highlighted how poorly the Afrotropical Region is studied, and strengthens the need for further sampling within the region as current records are very fragmented. This may result in the discovery of further new species, as many Afrotropical trachelines apparently have restricted distributions. Results of this dissertation have provided some clarity to Trachelinae taxonomy in the region, particularly with regards to general morphology and diagnostic characteristics of genera, and will also contribute to national and international initiatives, such as the South African National Survey of Arachnida (SANSA) and the African Arachnida Database (AFRAD), which aim to discover, describe and to make an inventory of the arachnid fauna of South Africa and Africa, respectively. However, to better understand the relationships between the genera a cladistic analysis should be performed on the subfamily, and should follow a revision of Paccius and the description of new genera from the region.
Afrikaans: Die sakspinnekopsubfamilie Trachelinae (Araneae: Corinnidae) word huidiglik in die Afrotropiese gebied deur agt genera verteenwoordig, naamlik Austrachelas Lawrence, 1938, Brachyphaea Simon, 1895, Cetonana Strand, 1929, Paccius Simon, 1897, Pronophaea Simon, 1897, Spinotrachelas Haddad, 2006, Thysanina Simon, 1910 en Trachelas L. Koch, 1872. Die genera Brachyphaea en Pronophaea is beide egter verkeerd geplaas, en behoort heel moontlik in die Corinninae, terwyl Austrachelas moontlik ‘n verteenwoordiger van die Gallieniellidae Millot, 1947 is. Verskeie hersienings is oor die Nuwe Wêreld en suid-oos Asië verteenwoordigers van die Trachelinae gemaak, terwyl min navorsing oor die fauna van die Afrotropiese Streek gedoen is. In hierdie verhandeling word ‘n oorsig van die literatuur gegee wat met die Afrotropiese verteenwoordigers van die Trachelinae verband hou, asook aspekte van ekologie, biologie en die mediese belang van hierdie spinnekoppe. ‘n Diagnose van die vyf geldige genera word verskaf, tesame met ‘n sleutel tot hierdie genera. ‘n Oorsig van drie genera, naamlik Cetonana, Thysanina en Trachelas in die Afrotropiese Streek, word gegee, met herbeskrywings van bekende spesies asook beskrywings van 58 nuwe spesies. Bykomende notas oor die biologie en verspreiding van hierdie spesies word, waar moontlik, verskaf. Eksemplare van 19 versamelings is ondersoek, met afmetings en genitale diagramme wat vir elke spesies verskaf word. Cetonana coenosa (Simon, 1897) en C. martini (Simon, 1897) is herbeskryf, en C. curvipes (Tucker, 1920), C. tridentata (Lessert, 1923) en C. simoni (Lawrence, 1942) is as junior sinonieme van C. martini voorgestel. Ten nuwe spesies is beskryf. Die tiepeksemplaar van C. aculifera (Strand, 1916) van Madagaskar kon nie opgespoor word nie. Dit is aanvaar dat hierdie eksemplaar vernietig is en dus word hierdie spesie as nomen dubium beskou. Binne die monotipiese genus Thysanina, is die tiepspesie T. serica Simon, 1910 herbeskryf asook vyf nuwe spesies van die Afrotropise Streek beskryf (Lyle & Haddad, 2006). Die genus Trachelas, met ‘n kosmopolitiese verspreiding, is vir die Afrotropiese vasteland hersien. Die spesies T. chubbi Lessert, 1921, T. pusillus Lessert, 1923, T. roeweri Lawrence, 1923, T. schenkeli Lessert, 1923, en T. sylvae Caporiacco, 1949 is herbeskryf. Agt-en-veertig nuwe spesies vanaf verskeie lokaliteite regdeur die streek is beskryf. Trachelas scopulifer Simon, 1896 is herbeskryf en die oorplasing na die genus Thysanina voorgestel. Die onvolowasse tiepeksemplaar van T. punctatus Simon, 1886 kon nie opgespoor word nie. Dit word aanvaar dat hierdie eksemplaar nie meer bestaan nie en dus word hierdie as nomen dubium beskou. Die resultate van hierdie verhandeling het duidelik die leemtes in die kennis van hierdie organismes in die Afrotropiese Streek uitgewys, en ondersteun en versterk die noodsaaklikheid vir verdere versameling binne hierdie gebied, aangesien huidige rekords baie gefragmenteer is. Dit sal heel moontlik die ontdekking van verdere nuwe spesies teweeg bring, aangesien talle verteenwoordigers van die Afrotropiese Trachelinae beperkte verspreiding vertoon. Resultate van hierdie verhandeling het helderheid verleen op die gebied van Trachelinae taksonomie in die streek, veral met betrekking tot die algemene morfologie en diagnostiese kenmerke van die genera, en sal ook bydra tot nasionale en internasionale inisiatiewe, soos die Suid-Afrikaanse Nasionale Opnames van Arachnida en die Afrika Arachnida Databasis (AFRAD), waarvan die doelwitte is om te ontdek, beskryf, asook ‘n inventaris van die Arachnida fauna van respektiewelik Suid-Afrika en Afrika te maak. ‘n Kladistieke analise sal egter op die subfamilie uitgevoer moet word ten einde die verwantskappe tussen genera beter te verstaan. Hierdie analise behoort voorafgegaan te word deur ‘n oorsig van Paccius asook die beskrywing van nuwe genera vanuit die streek.
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Dissertation (M.Sc. (Zoology and Entomology))--University of the Free State, 2008, Afrotropical, Cetonana, Diagnosis, New species, Sac spiders, Systematics, Trachelinae, Key, Thysanina, Trachelas, Xenopus, Xenopus laevis -- Parasites
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