DIPTERA The Order Diptera
CPIE Project Page A7
134a (105 / 20) Head well-developed, sclerotized, with mandibles that
move laterally NEMATOCERA [135]
134b Head sclerotized or not sclerotized, but having hooks that move
vertically BRACHYCERA [180]
135a (134) Behind a sclerotized head are 3 enlarged thoracic segments (may
appear as one segment) followed by 9 (including anal) narrower, abdominal
segments; a sclerotized tube on the last abdominal segment is used for
breathing at the water surface. Larva moving between water surface and
depth with a jerky, wriggling motion (wrigglers) Family Culicidae [136]
135b Behind sclerotized head all segments more or less the same size; sclero-
tized breathing tube not present. Larvae mosquito-like, but bent into
a U-shape Families Dixidae and Chironomidae
Dichotomous Key to Family Culicidae
136a (135) Sclerotized breathing tube at least as long as length of abdominal
segments VI, VII, and VIII, and bearing several groups of bristles;
sclerotization complete around anal segment (IX); a fan of yellow
bristles present below anal appendages, and a patch of short, yellow
spines on the lateral surface of segment VIII Culex quinquefasciatus
136b Breathing tube shorter, no longer than segments VII and VIII combined;
sclerotization of anal segment incomplete along ventral surface terminal
bristles on anal segment not forming a fan; one or two rows of dark
spines on sides of segment VIII Aedes [137]
137a (20) Breathing tube as long as segments VII and VIII, or nearly so;
a comb (single row) of dark, broad-based, posteriorly-directed spines
on lateral surface of abdominal segment VIII Aedes albopictus
137b Breathing tube short and stout, about as long as segment VIII; two
rows of spines present on the lateral surface of VIII Aedes aegypti
Also: Aedes nocturnus and Wyeomyia mitchelli
Also: 3 spp. of Toxorhynchites
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