Observations on the free larval stage of Glossina morsitans morsitans Westw. (Diptera, Glossinidae): the possibility of a larval pheromone

Publisher： Cambridge University Press

E-ISSN： 1475-2670|66|1|17-24

ISSN： 0007-4853

Source： Bulletin of Entomological Research, Vol.66, Iss.1, 1976-03, pp. : 17-24

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

Under simulated natural conditions the anal orifice of the larva of Glossina morsitans morsitans Westw. appears to open either at or soon after parturition. The larva burrows on average within two minutes of deposition; pupariation is completed 10–15 min later. Using methods that prevent burrowing and prolong the crawling period, certain larval movements were related to the pre-pupariation anal discharges and to the rapid spread of the fluid. Although the anus is not generally thought to be connected with the hind gut during the whole of larval life, the presence of uric acid in the discharges indicates that the fluid is a product of Malpighian tubule excretion. In a two-choice chamber in an incubator, flies larviposited significantly more often in the experimental pot if it contained a water- or ether-soluble extract of larval excretion in addition to any pupariating larvae. This points to the presence of a larval phero-mone which may attract gravid females to a breeding site.