A taxonomic revision of the ants of the Cardiocondyla wroughtonii group (Hymenoptera: Formicidae) with a checklist of the Cardiocondyla species of the world

Abstract

A revision of the Cardiocondyla wroughtonii group of the ant genus Cardiocondyla Emery 1869 is presented. The group is separable from other members of the genus by the character combination of a concave shape of postpetiolar sternite and a mesosoma not being stout and humpbacked. Eleven species were collected in this group – among these nine previously described species: Cardiocondyla wroughtonii Forel 1890, C. obscurior Wheeler 1929, C. shagrinata Seifert 2003, C. nana Seifert 2003, C. allonivalis Seifert 2023, C. yemeni Collingwood & Agosti 1996, C. yoruba Rigato 2001, C. neferka Bolton 1982 and C. weserka Bolton 1982. Cardiocondyla heinzei n.sp. is described as new from Ivory Coast whereas a species coded as Cardiocondyla sp. SPIT was only morphologically characterized without being validly described. The species are imaged in four standard viewing positions and data of 16 morphometric characters are presented. The heterospecific status of the closely related cosmopolitan tramp species Cardiocondyla wroughtonii and obscurior is confirmed by exploratory and hypothesis-driven data analyses based on 84 samples with 205 worker individuals. These analyses also confirmed, by investigation of type specimens, the junior synonymy of Cardiocondyla wroughtonii var. hawaiensis Forel 1899, C. wroughtonii subsp. quadraticeps Forel 1912, C. wroughtonii var. bimaculata Wheeler 1929, C. emeryi subsp. chlorotica Menozzi 1930, C. longispina Karavajev 1935 and C. yamauchii Terayama 1999 with C. wroughtonii and of C. bicolor Donisthorpe 1930 with C. obscurior. A checklist of the Cardiocondyla species of the world, including 127 published names of which 80 refer to valid species, is given at the end of the paper.

Keywords

• cryptic species
• numeric morphology-based alpha-taxonomy
• checklist Cardiocondyla