Mosquito Taxonomic Inventory

Variants:

Definition:

A cuticular projection that arises from a basal alveolus. Flattened setae with longitudinal ridges are known as scales (see scale).

Explanation:

Setae fall under two groups: single (unbranched) and branched. Single setae may be simple (with smooth surface) or bear short lateral processes that are not to be considered as branches. Single setae may have longitudinal ridges but unlike scales they are broadest at the base and taper distally. Branched setae have branches radiating from the base, originating as divisions of the main stem or arising along the length of the main stem (rachis). The descriptors used to name single setae include aciculate, barbed, brush-tipped, foliform, lanceolate, pectunculate, peg-like, simple, spiniform and spinulate; those used to name branched setae include bifurcated, dendritic, fan-like, forked, palmate, pectinate, plumose and stellate. The single setal names are used to describe the branches of branched setae. The types of setae are listed and defined below.

aciculate - Furnished with slender needle-like processes along the stem; the processes are somewhat flexible but often appear to be rigid.

barbed - With minute, short, heavy, pointed processes projecting obliquely from the surface.

bifurcated - With two branches of equal or nearly equal length arising together, usually below the distal third, commonly at the base.

brush-tipped - With numerous moderately long, slender processes arising apically.

dendritic - Branched to resemble a tree in form; having a stem-like part bearing irregular or dichotomous branches which may be repeatedly forked or branched in turn.

fan-like - With branches spreading out in a single plane from a short stem; in the case of some ventral brush setae the branches successively arise on one side of the stem; branches may be simple, barbed, aciculate or dendritic.

foliform - Flattened and leaf-like; similar to some scales but lacking longitudinal ridges.

forked - With a few branches arising beyond the basal third of the main stem.

lanceolate - Oblong or spear-shaped; tapering distally to a point.

palmate - With flattened, movable, usually horizontal branches radiating from a common point on a short stem.

pectinate - With long branches arising at regular intervals from one side of the main stem; a few small, sparsely arranged branches may arise from the opposite side.

pectunculate - With a row of short rigid processes resembling the teeth of a comb.

peg-like - A small cylindrical, usually blunt-tipped simple seta.

plumose - With numerous usually regularly arranged branches arising on either side of the main stem (rachis); the branches on either side may be directly opposite one another or alternate.

simple - Without lateral or apical processes.

spiniform - Thick, spine-like and usually not markedly attenuate or sharply pointed.

spinulate - Beset with small spine-like processes.

stellate - Tufted; with numerous stiff branches projecting at various angles from a single base; branches may be simple, barbed or aciculate. The term “stellate” refers to a condition where the rays (branches) project in all directions from a single point in the same plane. A better term would be “multiradiate” but owing to the long use of the term “stellate” in mosquito taxonomy it has been retained.

Synonyms: