External Morphology of Larvae of Belgica antarctica Jacobs, 1900 (Diptera, Chironomidae) Obtained from Two Locations in Maritime Antarctica.

Paraskeva Michailova,Pavlo A Kovalenko,Volodymyr A Gorobchyshyn,Julia Ilkova,Peter Convey,Iryna A Kozeretska

doi:10.3390/insects12090792

Abstract

Simple SummaryThe chironomid midge Belgica antarctica Jacobs is endemic to the western Antarctic Peninsula and South Shetland Islands. We provide the first detailed photomicrographic images of the fourth-instar larval head capsule and posterior parapods. We assessed variation in the morphology of larvae from two different collection locations off the coast of the western Antarctic Peninsula and compared it with that available in the literature. A number of differences were identified relating to the size of the larvae, the number of teeth on the mandibles, the number of antennal segments and the length of the antennal blade. Malformations of the mandible and mentum are reported for the first time in this species.The external morphology of the fourth-instar larva of the Antarctic endemic chironomid midge Belgica antarctica is described. Larvae were collected from Jougla Point (Wiencke Island) and an un-named island close to Enterprise Island, off the coast of the western Antarctic Peninsula. Light microscopy was used to examine and document photographically the structures of the mouthparts (mandible, mentum, premandible, labrum), antennae, pecten epipharyngis, clypeus, frontal apotome and posterior parapods. Measurements of the mouthparts are presented. The data obtained are compared with that available in the literature. A number of differences were identified relating to the size of the larvae, the number of teeth on the mandibles, the number of antennal segments and the length of the antennal blade. Malformations of the mandible and mentum are reported for the first time in this species. Features of larvae of taxonomic value that can be used to determine the species in larval stages are presented. These are of utility in using the larvae to reveal relationships with other species. Larvae are also important in ecological and genotoxicological studies, which require accurate species level identification.

Highlights

The brachypterous chironomid midge Belgica antarctica Jacobs is endemic to the western Antarctic Peninsula and South Shetland Islands
Usher and Edwards (1984) noted differences in the length of the head capsule of individuals obtained from two different Antarctic locations, and suggested that these may relate to the sex of the studied larvae or environmental differences [13]
Photomicrographs of some body parts of the fourth-instar larvae of the Antarctic endemic chironomid midge Belgica antarctica are presented for the first time

Summary

Introduction

Recent developments in understanding of this insect’s ontogenesis (some stages of which can be studied in vitro) and the large body of studies available make it an attractive model. Insects 2021, 12, 792 in vitro) and the large body of studies available make it an attractive model to study the effects of extreme conditions on biological processes at multiple levels of organization [7]. To study the effects of extreme conditions on biological processes at multiple levels of. The adult midge was first described in 1900 based on material collected during the organization ‘Belgica’ Expedition. The larvae were in first described bymaterial Rübsaamen (1906) [9], with. Was first described based on collected during the further information given by Roubard (1907) and

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