a handbook of the mosquitoes of north america - Systematic Catalog ...

CHAPTER I
CHARACTERISTICS OF MOSQUITOES
THEIR EXTERNAL ANATOMY. STRUCTURES USED IN CLASSIFICA-
TION, LARVAL AND PUPAL STRUCTURES,
INTERNAL ANATOMY
The mosquitoes or Culicidae belong to the Diptera, an order
of two-winged flies. They are characterized as small, soft
textured flies with long and slender abdomens, narrow wings
and the absence of the V-shaped suture on the thorax (Fig.
1). The males have bushy, plumose antennae (Fig. 2). The
most distinctive features are found in the wings (Fig. 5). The
costal vein surrounds the wing, the medial vein is only two
branched, and there is a marginal fringe of scales. The wing
veins also bear scales. In the females the mouthparts are
fitted for piercing and sucking.’ In the males the mouthparts
are not adapted for piercing and none are known to suck blood.
The larvae are all aquatic. The pupae are all aquatic and active.
EXTERNAL STRUCTURE OF THE ADULT
In order to identify and study mosquitoes, it is necessary to
know those structures involved in classification. A brief sum-
mary is here presented. As in all insects the body is divided
into three easily recognizable divisions-head, thorax and ab-
domen.
The Head
The head is nearly globose and is borne on a slender neck.
It bears t,he large eyes, the antennae and the mouthparts (Fig.
1). The ocelli are lacking. The antenna consists of fifteen
segments but the first segment is greatly reduced and may be
ignored for descriptive purposes. Assuming fourteen seg-
’ In the sub-family Chaoborinae the mouthparts are not fitted for
piercing.
1