Corthylus burgosi 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 : 19

Corthylus burgosi Atkinson , new species

Fig. 9 G, H ; Fig. 13 A–D

Diagnosis. This species appears to show characters intermediate between C. mexicanus and others in the group with truncate declivities. The circumdeclivital crest only occupies about 70% of the declivital circumference. Its coloration resembles C. mexicanus , one of several species that are bicolored with the disc of the pronotum and elytra paler than the anterior and posterior areas. The female frons is similar to that of C. mexicanus . It is distinguished from similar species by the very strongly costate elevation on the 1 st declivital interstriae which diverges from the sutural margin posteriorly, including C. mexicanus .

Female. Length: 2.39 mm, maximum width: 0.95 mm; length of elytra: 1.23 mm; length to width: 2.5; elytral length/total length: 0.51; elytral length/width: 1.29. (n = 4).

Frons deeply concave from epistoma to vertex. A yellow, waxy oval is present adjacent to the epistomal margin to the lower level of the eyes, slightly indented on the posterior margin. Surface of frons finely punctategranulate, without vestiture in the center. Short, erect setae present on the lateral margins of the concavity from the upper level of the eyes to vertex; these not long enough to curve inwards. Antennal club rounded. Both the first and second antennal sutures are marked by external grooves, the first partially septate. Antennal cirrus absent.

Anterior margin of pronotum truncate, with raised, undulate margin (i.e., asperities confluent). Anterior slope with broad, weakly raised asperities, becoming closely spaced parallel ridges at summit. Summit not strongly raised, anterior to middle. Pronotal disc smooth, shining, paler than anterior slope, with widely spaced, shallow punctures, some of which subtend short, semi-recumbent setae.

Elytral disc paler than posterior areas and declivity. Strial and interstrial punctures similar in size, confused, spaced by about 2× their diameters. Declivity abrupt, almost vertical, with prominently raised margin from apex, 70% of the distance to the base of the declivity. In the lower areas of the declivity the face is markedly depressed below the level of this margin. Interstria 1 with strongly elevated costa, in middle 2/3, beginning posterior top the base of the declivity and not reaching the apex. This costa diverging posteriorly from sutural margin, smoothly curved in lateral profile. Interstriae 2 impressed. Interstriae 3 slightly elevated appearing inflated but not costate, with 3–4 small, rounded granules. All interstrial setae on declivity narrow, apically pointed, spaced within rows by distance less than their lengths; present on costa of interstriae 1, base of interstriae 2, and on interstriae 3–5.

Male. Frons impressed, shallowly concave above epistoma; convex above to epistoma. Surface smooth, with a moderate number of shallow punctures, with sparse micropunctures between them. Antenna smaller than that of female, more symmetrical, sutures 1 and 2 clearly marked externally. Anterior margin of pronotum with a row of low asperities, the middle pair larger than the rest. Identical to females in all other characters of the pronotum, elytra, and declivity.

Type material. Holotype female. Mexico: Michoacán: Uruapan, 2019, light trap, H. Oliviera ( CNIN) . Allotype. Same data ( CNIN) : Paratypes. Same data ( UTIC, 1 female) ; Morelos: Huitzilac, Colonia Monte Cristo , 2,207 m, 17-VII-2015, 4- vane flight trap, N. Hernández and A. Burgos ( UTIC, 1 male) .

Etymology. This species is named after Dr. Armando Burgos Solorio in recognition of his numerous contributions to the knowledge of the Scolytinae and Platypodinae of Mexico. He was also the collector of the first known specimen.

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 13.Corthylus burgosi, new species, female holotype.A) Dorsal habitus.B) Lateral habitus.C) Frons and antenna. D) Declivity. All photographs by the author.