﻿SOLOMON ISLANDS TRIPTEROIDES — BELKIN 215 



genus Tripteroides the Papuan element of New Guinea predominates 

 in the Solomon Islands but has not played a prominent part in the 

 population of the islands east of the Solomons. On the other hand, 

 the temperate Australian element has supplied more of the forms now 

 known to occur in these islands and has even extended into the Solomon 

 Islands. 



BIOLOGY 



All the species of Tripteroides whose immature stages are known 

 have been found breeding in small water collections in tree holes, 

 bamboo, coconut shells, leaf-axils and flower bracts of plants, and 

 especially in the pitchers of Nepenthes. A few species occur also in 

 artificial containers, and one has been found on one occasion in a rock 

 hole. The association of Tripteroides with the carnivorous Nepenthes 

 has been discussed by Lloyd (1942) from a physiological standpoint. 

 It has been noted by several students of Tripteroides (Edwards, Brug, 

 Lee) that frequently members of this genus are the only mosquitoes 

 present in the pitchers of Nepenthes and that a great number of species 

 probably await discovery when the interior areas of Borneo and New 

 Guinea are studied, as the genus Tripteroides reaches its peak of 

 speciation in this ecological niche. 



In the Solomons numerous collections have been made in a wide 

 variety of breeding places, and Tripteroides has been found to conform 

 very well with previously reported habitats except for the lack of 

 collections in Nepenthes. Apparently this pitcherplant is absent from 

 coastal areas. No specific records of Nepenthes from the Solomons 

 were found in botanical literature. It is probable that several species 

 of Nepenthes will be found when searched for in the proper places in 

 the Solomons, since this genus is abundantly known in New Guinea 

 and is represented by several species in New Caledonia. J. G. 

 Franclemont informs me that he saw pitchers of Nepenthes collected 

 at high elevations on Kolumbangara Island. 



Table 4 shows the habitats of the immature stages of Tripteroides 

 species in the Solomon Islands and the percentage of collections of 

 each species in the different habitats. It will be noted that out of 

 eight species whose immature stages are known, six breed in tree holes, 

 four of these preferring this habitat to others. T. solomonis has been 

 found more frequently in artificial containers than any natural breed- 

 ing place. Three other species also breed in artificial containers. 

 Bamboo stubble is used by three species also, coconut shells by two. 

 T. m.athesoni is restricted to the leaf-axils of taro plants {Alocasia sp., 

 Colocasia sp.) , and T. hinotata occasionally utilizes them. The larval 

 habitat of floridensis is particularly unusual in that the leaf-axils of 

 banana plants in the Solomon Islands apparently never hold water but 

 usually contain only a small amount of muck. Several hundred 



