Corthylus latisetosus Atkinson, 2020

Atkinson, Thomas H., 2020, New species, new records and synonymy of Mexican Corthylus Erichson, 1834 (Coleoptera: Curculionidae: Scolytinae), Insecta Mundi 2020 (792), pp. 1-25 : 16-19

Corthylus latisetosus Atkinson , new species

Fig. 9 E, F ; Fig. 12 A–D

Diagnosis. This species can be recognized by its small size. The circumdeclivital ring is about 80% complete, with the raised lateral margin not present near the base of the declivity. Unlike several other species (e.g., C. ibarrai ),

the face of the declivity is not strongly recessed with respect to the circumdeclivital ring. Most declivital interstriae have rows of stout, truncate setae.

Female. Unknown.

Male. Length: 1.55 mm, maximum width: 0.6 mm; length of elytra: 0.8 mm; length to width: 2.6; elytral length/ total length: 0.52; elytral length/width: 1.33. (n = 1).

Frons flattened, shining, without vestiture. Surface finely reticulate, with widely spaced, shallow punctures. Frontal setae absent. Epistomal margin elevated, with a transverse impression immediately above. Antennal club almost oval; suture 1 marked by external groove, partly septate; suture 2 marked by external groove.

Anterior margin of pronotum with low asperities, the central pair largest. Anterior slope with short, weakly elevated asperities. Pronotal summit low, slightly anterior to center. Disc smooth, shining, with widely separated, shallow punctures.

Strial punctures on elytral disc similar in size, slightly confused. Surface smooth, shining, striae not impressed. Some interstrial punctures with short setae in lateral areas. Declivity abruptly truncate with a prominent circumdeclivital elevation from apex, extending 80% of the distance to the declivital base. Face of declivity not impressed with respect to elevated margin. Declivital interstriae 1 weakly elevated, subserrate; elevation not reaching base or apex of declivity. Strial and interstrial punctures similar in size, partly confused. Short, erect, truncate, flattened setae present on most declivital interstriae, their length less than spacing within rows or between rows.

Type material. Holotype male. Mexico: Michoacán: Uruapan, Zumpimito , 19.3336 N, 102. 0592 W, 12-XI-2016; flight intercept trap, M. Lázaro D. ( CNIN).

Etymology. The name was chosen because of the wide, truncate interstrial setae on the face of the declivity.

Figures

Figure 9. Mexican and Central American species with truncate declivity (1 of 2). A, B) C. ibarrai new species, holotype. C, D) Holotype, C. serratus Wood. E, F) C. latisetosus new species, holotype. G, H) C. burgosi new species, holotype. I, J) C. mexicanus Schedl. Photographs A–B, E–J by the author, C–D by S.M. Smith (Copyright National Museum of Natural History, Smithsonian Institution, Washington, D.C., published by permission).

Figure 12. Corthylus latisetosus, new species, male holotype. A) Dorsal habitus. B) Lateral habitus. C) Frons and antenna. D) Declivity. All photographs by the author.