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Karl Kjer taxon links [down<--]Sericostomatoidea Interpreting the tree
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Containing group: Sericostomatoidea


The family was established by Scott (1985) for 2 species from South Africa, Petrothrincus circularis Barnard and P. triangularis (Hagen) (originally described from the case only and included in Molanna); Scott (1993) later described a 3rd South African species, P. demoori and expanded the diagnosis and description of the family. All of the South African species are endemic to the Cape Province. Weaver (1997) recorded the family from Madagascar for the first time and described 3 additional species in a new genus, Gyrocarisa Weaver, to which 2 other species were added later by Malm and Johanson (2005). Recently, Gyrocarisa was synonymized with Petrothrincus by Johanson and Olah (2006), who described 5 additional Malagasy species. As of now, the family contains a single genus, Petrothrincus, containing 14 species from South Africa and Madagascar.  From Holzenthal et al. (2007a).


The larvae live in small, cool streams in the mountains and foothills in fast flowing riffles as well as pools. They construct broad, depressed, limpet-like cases similar to those seen in European Thremma, some North American Ceraclea, and in Chilean Eosericostoma; at least among the South African species the case can be circular or triangular. Larvae feed as scrapers on periphyton and the organic sediment that collects on the surfaces of rocks. Weaver (1997) noted several modifications of the female abdomen and wings, including long hairs on the hind wings, for holding the large eggmass above the abdomen and between the folded wings, possibly in a protective posture.  From Holzenthal et al. (2007a).

Discussion of Phylogenetic Relationships

In his original description of the genus, Barnard (1934) could not place Petrothrincus within any known family and referred it only to “Aequipalpia.” Fischer (1964, 1972) and others continued to catalog the genus within the Molannidae. Holzenthal et al. (2007b) place the family as the sister taxon to another South African endemic, Hydrosalpingidae.


Barnard, K.H. (1934) South African caddis-flies (Trichoptera). Transactions of the Royal Society of South Africa, 21, 291394.

Holzenthal R.W., Blahnik, R.J., Prather, A.L., and Kjer K.M. 2007a. Order Trichoptera Kirby 1813 (Insecta), Caddisflies. In: Zhang, Z.-Q., and Shear, W.A. (Eds). 2007 Linneaus Tercentenary: Progress in Invertebrate Taxonomy. Zootaxa. 58 pp. 1668:639-698

Holzenthal R.W., Blahnik, R.J., Kjer K.M and Prather, A.L. 2007b. An update on the phylogeny of Caddisflies (Trichoptera). Proceedings of the XIIth International Symposium on Trichoptera. Bueno-Soria, R. Barba-Alvearz and B. Armitage (Eds). pp. 143-153. The Caddis Press.

Fischer, F.C.J. (1964) Phryganeidae, Limnocentropodidae, Molannidae. Trichopterorum Catalogus 5. Nederlandsche Entomologische Vereeniging, Amsterdam, vi + 214 pp.

Fischer, F.C.J. (1972) Supplement to Vol. III and IV. Trichopterorum Catalogus 13. Nederlandsche Entomologische Vereeniging, Amsterdam, vii + 172 pp.

Johanson, K.A. & Olah, J. (2006) Eleven new species of Sericostomatoidea from Madagascar (Trichoptera: Helicopsychidae, Petrothrincidae, Sericostomatidae). Zootaxa, 1205, 130.

Malm, T. & Johanson, K.A. (2005) Descriptions of two new species of Gyrocarisa (Trichoptera: Petrothrincidae) from Madagasca. Zootaxa, 1009, 1520.

Scott, K.M.F. (1985) Order Trichoptera (caddis flies). In: Scholtz, C.H. & Holm, E. (Eds.) Insects of Southern Africa. Butterworths, Durban, pp. 327340.

Scott, K.M.F. (1993) Three recently erected Trichoptera families from South Africa, the Hydrosalpingidae, Petrothrincidae and Barbarochthonidae (Integripalpia: Sericostomatidae) [with a contribution by F.C. de Moor]. Annals of the Cape Provincial Museums (Natural History), 18, 293354.

Weaver, J.S., III. (1997) A new genus of Petrothrincidae (Trichoptera) from Madagascar with specialized modifications in the female terminalia for carrying the eggmass. In: Holzenthal, R.W. & Flint, O.S., Jr. (Eds.) Proceedings of the 8th International Symposium on Trichoptera. Ohio Biological Survey, Columbus, Ohio, pp. 467474.

About This Page

Karl Kjer
Rutgers University, New Brunswick, New Jersey, USA

Correspondence regarding this page should be directed to Karl Kjer at

Page: Tree of Life Petrothrincidae. Authored by Karl Kjer. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.

Citing this page:

Kjer, Karl. 2010. Petrothrincidae. Version 20 July 2010 (under construction). http://tolweb.org/Petrothrincidae/14643/2010.07.20 in The Tree of Life Web Project, http://tolweb.org/

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