Tragidion coquus Linnaeus

Swift, Ian & Ray, Ann M., 2008, A review of the genus Tragidion Audinet-Serville, 1834 (Coleoptera: Cerambycidae: Cerambycinae: Trachyderini), Zootaxa 1892, pp. 1-25 : 16-17

Tragidion coquus Linnaeus

( Figs 2 E–F, 3A, 6D)

Cerambyx coquus Linnaeus, 1758:393 . Type locality: Canada

Callidium lynceum Fabricius, 1775:191 ; Fabricius, 1801:344. Type locality: Cape of Good Hope.

Cerambyx lynceus: Olivier, 1795:37

Lamia coquus: Fabricius, 1801:300

Callidium fulvipenne Say, 1823:414 . Type locality: “Arkansa River, Arkansa”.

Cerambyx (Purpuricenus) Melsheimeri Germar, 1824:502 . Type locality: America spetentrionalis.

Tragidion coquus: Audinet-Serville, 1834:90 ; LeConte, 1850:10; Leng, 1886:81; Casey, 1893:586; Beutenmüller, 1896:76; Knull, 1946:229

Tragidion fulvipenne: LeConte, 1850:10 ; Casey, 1893:586; Casey, 1912:323.

Tragidion coquus var fulvipenne: Leng, 1886:81 ; Knull, 1946:229.

Tragidion coquus filicorne Casey, 1912:323 . Type locality: “New Mexico (Las Vegas) and Texas”.

Tragidion fulvipenne nubifer Casey, 1912:323 . Type locality: Texas.

Tragidion fulvipenne levipes Casey, 1912:323 . Type locality: “New Mexico (Las Vegas)”.

Tragidion apicatum Casey, 1912:323 . Type locality: Texas.

Material examined: 167 specimens. We were unable to locate types for this species.

Diagnosis. Throughout the eastern portions of its range, this species is distinctive in North America . It can be differentiated from most US species by the combination of entirely black antennae, feeble elytral costae, slender body form, and slender metatibiae. Outside of the US, this species resembles T. bicolor . For a discussion of the differences between these two species, see the account of T. bicolor .

Tragidion coquus is the most polymorphic species in the genus. Numerous color variants of the elytra occur throughout the range of this species. These range from entirely black to bright orange, and can include two round orange or black maculae on the humeral region of the elytra. Color pattern does not seem to be correlated with sex of the individual, geography, or phenology.

Hovore and Giesbert (1976) discussed a population of what they believed to be T. coquus from western Texas that exhibited characters of both T. coquus and possibly T. annulatum and T. auripenne . Of these three species, this population appears most similar to T. coquus . Males of this population can have annulated or entirely black antennae with intergrades thereof, and four or (rarely) five elytral costae. This population may represent hybridization between T. densiventre and T. coquus ; T. annulatum is confined to the west coast of North America , and not found within the range of these two species.

Due to the variation between four and five elytral costae, and the variation between black and annulated antennae, this species appears in three different couplets in the key to the males. In the female key, this species appears twice due to the variation in the costae, however, the antennae of all females examined has consistently been black.

Distribution ( Fig. 6 D). Central and eastern USA as well as southeastern Canada; west to southern New Mexico and western Texas. The putative hybrid populations occur in western Texas and eastern New Mexico.

Ecology. This species is common and widespread over much of the eastern and central United States, where the larval hosts include a variety of hardwoods, especially Quercus spp. ( Linsley, 1962). In Texas and New Mexico, adults of this species are commonly collected in xeric habitats without Quercus . Therefore, several widely-divergent larval hosts are utilized, at least in the southwestern portions of its range.

Figures

FIGURE 2. Dorsal habitus photos of Tragidion spp. A, Tragidion auripenne (male); B, T. auripenne (female); C, T. bicolor (male); D, T. bicolor (female); E, T. coquus (male); F, T. coquus (male).

FIGURE 6. Distribution map of Tragidion spp. A, Tragidion armatum; B, T. bicolor; C, T. carinatum; D, T. coquus; E, T. dichromaticum.