Intercontinental Triaenonychidae—the case of Ceratomontia (Opiliones, Insidiatores)

Abstract

Among the 64 genera of Triaenonychinae Sorensen 1886 (Opiliones, Insidiatores), two are found in more than one continent: Ceratomontia Roewer 1915 and Nuncia Loman 1902, both occurring in South America, the former occurring also in South Africa, the latter in New Zealand. Until now there were 22 valid species of Ceratomontia, diagnosed mainly by the tarsal formula. In the present paper, a cladistic analysis was performed to test the monophyly of Ceratomontia and study its relationship with the South African triaenonychine genera Austromontia Lawrence 1931 and Monomontia Lawrence 1931. A total of 42 morphological characters were coded for 18 terminal taxa, 14 representing the genera Ceratomontia (from South America and South Africa), Austromontia and Monomontia as ingroup, and two species of Triaenonychinae from South America, one from South Africa and one Adaeinae Pocock 1902 from South Africa as outgroups. The analysis using heuristic search algorithms resulted in 12 most parsimonious trees (L 5 95, CI 5 0.52, RI 5 0.66). The consensus hypothesis did not recover a monophyletic Ceratomontia, instead, the South African species constitute a clade with the Austromontia and Monomontia species. The Ceratomontia species from South America form a clade that is sister-group of the clade formed by the South African genera of the ingroup. The result shows that Ceratomontia is involved in a ''Gondwanan relationship,'' but also includes other genera, suggesting that it is not a monophyletic group.