Fossil-record

Trichoptera World Checklist (TWC) [ http://entweb.clemson.edu/database/trichopt/search.htm ], as at July 2006, recorded 12,627 species, 610 genera and 46 families of extant and in addition 488 species, 78 genera and 7 families of fossil Trichoptera. An analysis of the 2001 TWC list of present-day Trichoptera diversity at species, generic/subgeneric and family level along the selected Afrotropical, Neotropical, Australian, Oriental, Nearctic and Palaearctic (as a unit or assessed as Eastern and Western) regions reveals uneven distribution patterns. The Oriental and Neotropical are the two most species diverse with 47--77% of the species in widespread genera being recorded in these two regions. Five Trichoptera families comprise 55% of the world's species and 19 families contain fewer than 30 species per family. Ten out of 620 genera contain 29% of the world's known species. Considerable underestimates of Trichoptera diversity for certain regions are recognised. Historical processes in Trichoptera evolution dating back to the middle and late Triassic reveal that the major phylogenetic differentiation in Trichoptera had occurred during the Jurrasic and early Cretaceous. The breakup of Gondwana in the Cretaceous led to further isolation and diversification of Trichoptera. High species endemism is noted to be in tropical or mountainous regions correlated with humid or high rainfall conditions. Repetitive patterns of shared taxa between biogeographical regions suggest possible centres of origin, vicariant events or distribution routes. Related taxa associations between different regions suggest that an alternative biogeographical map reflecting Trichoptera distribution patterns different from the Wallace (The Geographical Distribution of Animals: With a Study of the Relations of Living and Extinct Faunas as Elucidating the Past Changes of the Earth's Surface, Vol. 1, 503 pp., Vol. 2, 607 pp., Macmillan, London, 1876) proposed biogeography patterns should be considered. Anthropogenic development threatens biodiversity and the value of Trichoptera as important functional components of aquatic ecosystems, indicator species of deteriorating conditions and custodians of environmental protection are realised.

Author Affiliation:

(1) Department of Freshwater Invertebrates, Makana Biodiversity Centre, Albany Museum, Grahamstown, 6139, South Africa

(2) Department of Zoology and Entomology, Rhodes University, Grahamstown, 6139, South Africa

(3) Department of Entomology, Faculty of Biology, St. Petersburg State University, Universitetskaya nab. 7/9, St. Petersburg, 19034, Russia

Article History:

Registration Date: 18/07/2007

Online Date: 18/12/2007

Article note:

Guest editors: E. V. Balian, C. Leveque, H. Segers & K. Martens

Freshwater Animal Diversity Assessment




Source Citation:Moor, F. C., and V. D. Ivanov. "Global diversity of caddisflies (Trichoptera: Insecta) in freshwater.(Author abstract)(Report)." Hydrobiologia 595.1 (Jan 2008): 393(15). Academic OneFile. Gale. BROWARD COUNTY LIBRARY. 11 May 2009
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