The ecological tale of Gonyleptidae (Arachnida, Opiliones) evolution: phylogeny of a Neotropical lineage of armoured harvestmen using ecological, behavioural and chemical characters.

Abstract

The large Neotropical family Gonyleptidae comprises nearly 820 species divided into 16 subfamilies. The majority of publications on harvestman ecology, behaviour and scent gland secretion chemistry have focused on this family. We used the information available in the literature and combined it with an intensive search for ecological, behavioural and chemical data to infer the phylogeny of the Gonyleptidae. We included 28 species belonging to 14 of the 16 gonyleptid subfamilies in the ingroup and four species belonging to the families Cosmetidae, Stygnidae and Manaosbiidae in the outgroup. We performed the analyses using equally weighted characters and coded 63 characters comprising 153 states, which makes this the largest non-morphological, non-molecular phylogenetic data matrix published to date. We obtained five most parsimonious trees, and the strict consensus resulted in six collapsed nodes. The results show that the monophyly of Gonyleptidae is equivocal because Metasarcinae is placed at a basal polytomy with the outgroups Cosmetidae and Stygnidae. Gonyleptinae, Pachylinae and Progonyleptoidellinae are polyphyletic groups, but the remaining subfamilies are monophyletic and have several synapomorphies. Based on the resulting topology, we discuss the performance of ecological, behavioural and chemical characters, and map a selected set of characters to discuss their evolutionary patterns in the family.