Revision of the taxonomy of the larvae of the subfamily Eutrombidiinae (Acarina : Microtrombidiidae)

Abstract

The subfamily Eutrombidiinae of the Trombidioidea (Acarina) is revised, and placed with the Microtrombidiinae in the family Microtrombidiidae; it is divided into the three tribes Eutrombidiini, Hexathrombiini, trib, nov., and Milliotrombidiini, trib. nov., with differing biological characters as well as taxonomic. The division is made for the larvae, as adult-larva correlations are known only for Eutrombidium.

Eutrombidiini is left with two genera: Verdunella, gen. nov., monotypic with V. lockleii (Welbourn & Young) from Araneida, North America, and Eutrombidium Verdun, cosmopolitan from Orthoptera, principally Acrididae, with the following species recognised as larvae: E. centrale, sp, nov., E. occidentale, sp. nov., E. orientale, sp. nov. (North America), E. trigonum (Hermann) (western Europe), E. africanum, sp. nov., E. macfarlanei, sp. nov. (Niger, west Africa), E. verdense, sp. nov. (Cape Verde Islands, Atlantic), E. robauxi, sp. nov. (Corfu, Turkey), E. feldmanmuhsamae Feider (Israel), E. indicum, sp. nov. (India), and E. australiense, sp. nov. (Australia). The following nominal taxa (larvae) are left unkeyed: E. debilipes (Leonardi) (western Russia), E. locustarum (Walsh) (North America), E. odorheiense Feider (Romania) (with subspecies E. o. odorheiense Feider and E. o. littorale Feider), and E. townsendi (Dumbleton) (New Zealand).

Larvae of the Hexathrombiini are ectoparasitic on Coleoptera (one exception); genera indude Hexathrombium Cooreman, Hoplothrombium Ewing and Beronium Southcott. Hexathrombium has two species, H. spatuliferum Cooreman (on carabid beetle, former Belgian Congo), and H. willisi, sp. nov. (on cicindelid beetle, North America). Hoplothrombium is known from H. quinquescutatum Ewing (on ‘beetle mite’, i.e. Oribatei, Acarina, in toad's stomach, North America). Beronium is known for B. coiffaiti (Beron), an eyeless form (from cavernicolous carabid beetle, North Africa).

Milliotrombidiini larvae are ectoparasites of Myriapoda; genera include Milliotrombidium Shiba, with M. milliopodum Shiba (from millipede, Malaya) and Kepongia, gen, nov., with K. malayensis, sp. nov. (from centipede, Malaya).

Names are assigned to the various specialised setae on tarsus III of the larvae with ‘deformed’ claws, i.e. with tarsus III modified for saltation.