Identification Keys

Even though the tiger beetles are one of the most intensely studied beetle groups, keys for the identifying the North American fauna are difficult to come by. Many of the available keys are useful only in certain regions or states, while others are in dire need of revision and updating. This article will be the first in a series of articles designed to provide keys and information for the identifying all North American and most Central American tiger beetle species and subspecies.

Eleven genera of tiger beetles occur in North and Central America. All of these genera, with the exception of Cicindela, are rather small (anywhere between one and ten species each) and more or less restricted in distribution. The genus Cicindela is quite large (contains almost 200 species) and is distributed throughout North and Central America.

The following key to the tiger beetle genera is adapted from Willis (1969).

A KEY TO THE TIGER BEETLE GENERA OF NORTH AND CENTRAL AMERICA (COLEOPTERA: CICINDELIDAE)

1. Metepisternum narrow, with groves anteriorly; mesepisternum strongly elongated; lacinia of maxilla without digitus (Collyrinae)........... .......................................Ctenostoma Klug

-- Metepisternum relatively broad, without anterior groove; mesepisternum usually short; lacinia with digitus (Cicindelinae)............2

2. Anterior corners or pronotum more advanced than anterior margin of prosternum; 4th segment of maxillary palpus almost always shorter than 3rd.... (Megacephalini) ..................................................3

--   Anterior corners of pronotum not more advanced than anterior margin of prosternum; 4th segment of maxillary palpus almost always longer than 3rd... .(Cicindelini).............................................. 8

3. Palpiger of labial palpus reaching at most the mentum notch; elytra without humeral angles or markings....................................4

-- Palpiger of labial palpus clearly surpassing mentum notch (almost invariably very long); elytra with variously developed humeral markings usually present ...................................................................5

4. Elytral epipleura punctate front tarsi of male not dilated nor setose on underside ............................................................ Amblychila Say

-- Elytral epipleura impunctate; front tarsi of male dilated and setose on the underside ......................................................... Omus Eschscholtz

5. Lateral margins of elytra with stridulating organs; labrum long, with marginal setae ................................................................6

-- Elytra without stridulating organs; labrum often short, often with submarginal setae .............................................................7

6. Last tarsal segment normal, sparsely setose beneath; first three segments of anterior tarsi of male strongly widened ....Oxychila Dejean

-- Last tarsal segment thickened, densely setose beneath; first three segments of anterior tarsi of male scarcely widened ......Chiloxia Guerin

7. Labrum mostly short and transverse, never with median tooth, almost always with submarginal setae; palpi mostly yellow; clypeus with lateral setae.............................................. Megacephala Latreille

-- Labrum long and narrow, with median tooth; with lateral setae; labrum and all appendages black; clypeus bald ........... Pseudoxychila Guerin

8. Head, pronotum, pro- and mesosternum, base of abdomen or base of elytra setose, OR posterior one-third of elytra with whitish sutural or discal markings........................ Cicindela L.

--Head, pronotum, pro- and mesosternum, base of abdomen or base of elytra glabrous; posterior one-third of elytra never with whitish sutural or discal markings........................................................9

9. Epipleura of elytra and free lateral margin of hind coxae glabrous; middle of frons with at least one transverse impression; labrum without median tooth and with seven setae ................................. Iresia Dejean

--   Epipleura of elytra rarely setose; free lateral margin of hind coxae setose ................................................................................10

10. Fifth tarsal segment of hind tarsu inserted on upper surface of 4th segment; mentum with a sensory seta on either side of median tooth.............................................................Oxygonia Mannerheim

-- Fifth tarsal segment of hind tarsi inserted apically; mentum without setae on either side of median tooth; elytral epipleura glabrous ........ Odontochila Castelnau

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