﻿SOLOMON ISLANDS TRIPTEROIDES — BELKIN 209 



acters to separate species. The pupae of this genus have never been 

 described or figured in detail. I have found the single cephalothoracic 

 hair 1 of Rachisoura a good character to separate this subgenus from 

 Mlmeteomyia and Tripteroides^ which have this hair 2- or 3-branched. 

 The development of hairs 2 and 3 on the cephalothorax may also be of 

 considerable value. On the abdomen the development of hairs B on 

 the various segments will undoubtedly show good differential charac- 

 ters and may even be of subgeneric value. The position of hair C 

 has been useful in separating related species and has also indicated 

 group relationship. The development of hair 2 on segment II also 

 shows distinct possibilities. 



GENERAL CONSIDERATIONS 



THE GENUS TRIPTEROIDES GILES 



The genus Tripteroides has been well characterized by Edwards 

 ( 1932) and also by Lee ( 1946) . There is nothing to add at the present 

 to their diagnosis of the larvae and adults. For the purpose of recog- 

 nition of Tripteroides in the Solomons, a brief summary of the dis- 

 tinctive features is given here. The characters of the pupae are also 

 listed. 



Adults. — Vein 6 reaching beyond base of fork of vein 5; squama 

 partially fringed. Pronotal lobes well developed, separate, larger 

 than ineron ; meron in line with the base of the hind coxa. Pleural 

 bristles reduced: spiraculars pr&sent; posterior pronotal usually one 

 (three or four in Maorigoeldia) or absent; postspiraculars and lower 

 mesepimerals absent ; upper sternopleurals absent or at most weakly 

 developed; postnotals sometimes represented by a few short hairs; 

 propleurals one or more; other pleural bristles present but poorly 

 developed. Pulvilli absent. Antennae of male usually conspicuously 

 plumose, the last two segments elongate. Proboscis not swollen at 

 the tip, usually long and slender. Palpi of male short to almost as 

 long as the proboscis. Head with flat scales only, except for occipital 

 erect scales. Abdomen with very few hairs. Male genitalia with 

 simple mesosome; tenth sternite with one or more teeth at the apex; 

 ninth tergite usually emarginate, with bristly lobes ; sidepiece with a 

 poorly developed bristly basal lobe; clasper long, simple, with short 

 apical spine. 



Larvae. — Ventral brush reduced to a pair of tufts or even a single 

 pair of hairs; saddle of anal segment incomplete. Siphon without 

 acus ; with numerous dorsal, or dorsal and dorsolateral, hairs or spikes; 

 numerous ventral tufts distributed from base to apex ; pecten always 

 present, of variable extent. Comb scales in a single row (except in 

 Maorigoeldia)^ arising independently or from a sclerotized plate. 

 Antennae very short, smooth. Mouthparts unmodified except in 



