Pristomyrmex tsujii sp. n. and P. mandibularis Mann (Hymenoptera, Formicidae) from Fiji

Eli Sarnat,Evan Economo

doi:10.3897/zookeys.340.5479

Abstract

Pristomyrmex tsujii sp. n., an endemic species of the Fiji islands, is described from the worker, ergatoid queen, alate queen and male castes. The alate queen and male castes of Pristomyrmex mandibularis Mann are also described for the first time. The ergatoid queens for both species appear to be morphologically intermediate between the worker and alate queen castes. Pristomyrmex tsujii is readily distinguished from Pristomyrmex mandibularis by the lack of well-developed propodeal spines. Although both species occur across the Fijian archipelago, they are rarely encountered and workers are most often collected from sifted litter. The descriptions are illustrated with specimen photographs, line drawings and a distribution map.

Highlights

Pristomyrmex Mayr is a genus composed of 59 extant valid species restricted to the Old World tropics (Bolton 2013)
On Viti Levu, the cephalic sculpture of P. mandibularis varies along geographical gradients, whereas on Koro colonies exhibiting the two extremes of the sculpture spectrum occur sympatrically without any known intermediates 10 Taxonomic characters of the mandibles and anterior head capsule used in combination to separate Pristomyrmex species from all other Fijian myrmicines
Despite being widely distributed across the Fijian archipelago, workers of Pristomyrmex tsujii were rarely encountered in the field, males were collected in Malaise traps with some frequency

Summary

Introduction

Pristomyrmex Mayr is a genus composed of 59 extant valid species restricted to the Old World tropics (Bolton 2013). Intermorph queens are a regularly produced caste that retain all reproductive functions of alate queens and can co-occur with alate queens The latter condition more accurately applies to both species of the Fijian Pristomyrmex, we continue to use the term ergatoid to describe the permanently wingless queen caste as it is broadly accepted across myrmecology and more facilitates comparative studies (Peeters 2012). This taxonomic treatment of P. tsujii and P. mandibularis is part of an ongoing effort to characterize the systematics, ecology and evolution of the Fijian ant fauna (Economo and Sarnat 2012; Lucky and Sarnat 2008, 2010; Sarnat 2006, 2008; Sarnat and Economo 2012; Sarnat and Moreau 2011). Geographic coordinates presented in the material examined sections are given in decimal degrees, rounded to the fourth significant digit where accuracy permits

Methods and abbreviations

Discussion