Convergent fighting behavior in two species of Neotropical harvestmen (Opiliones): insights on the evolution of maternal care and resource defense polygyny

Author(s)

Garcia-Hernandez, Solimary ^[1] ; Machado, Glauco ^[2]

Affiliation

^[1] Univ Sao Paulo, Inst Biociencias, Programa Posgrad Ecol, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Biociencias, LAGE Dept Ecol, BR-05508090 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: JOURNAL OF ARACHNOLOGY; v. 46, n. 1, p. 165-169, APR 2018.
• Web of Science Citations: 0

Abstract

Males of several harvestman species fight for the possession of oviposition sites. Usually, males use spines and elongated appendages as weapons in these fights. Although males of many cranaids have spines that could be used as weapons, there is no report of male-male fights in this family. Here we describe the first case of a male-male fight in cranaids. Males of Phareicranaus aff. spinulatus face each other, extend their second pair of legs laterally, and use them to hit the second legs of the opponent. Pedipalps are kept above the chelicerae and not used to strike the opponent. The fighting behavior is remarkably similar to that described for Goniosomatinae (Gonyleptidae). We interpret morphological and behavioral similarities between cranaids and goniosomatines as convergences. Moreover, we suggest that body/egg size and predation pressure may have influenced the evolution of parental care and resource defense polygyny in these two harvestman clades. (AU)

• FAPESP's process: 15/10448-4 - Interplay between paternal care and sexual selection in harvestmen
• Grantee: Glauco Machado
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/05283-1 - Implications of autotomy of metasoma for locomotion, reproduction, foraging, and defense in scorpions
• Grantee: Solimary García Hernández
• Support Opportunities: Scholarships in Brazil - Doctorate