Hylurgops

Mercado-Vélez, Javier E. & Negrón, José F., 2014, Revision of the new world species of Hylurgops LeConte, 1876 with the description of a new genus in the Hylastini (Coleoptera: Scolytinae) and comments on some Palearctic species, Zootaxa 3785 (3), pp. 301-342 : 315-316

Key to the New World Hylurgops

1 Pronotum slightly wider than long (0.92 ± 0.4, N= 109), distinctly constricted anteriorly ( Fig. 14 a); mature color reddish-brown to dark brown, never black............................................................................. 2

- Pronotum slightly longer than wide (1.04 ± 0.4, N= 118), not constricted but smoothly tapering anteriorly ( Fig. 14 b); mature color dark reddish-brown to black........................................................................ 5

2 (1) Smaller species (2.5–3.4 mm); declivital apex upturned ( Fig. 15 a); elytral striae more distinctly impressed; granules larger; mature color brown to reddish-brown................................................. palliatus ( Gyllenhal, 1813)

- Larger species (3.7–5.6 mm); declivital apex rounded, not upturned; elytral striae less distinctly impressed; declivital granules smaller; mature color brown to black...................................................................... 3

3 (2) Dorsal surfaces dull; pronotal interspaces coarse, punctures deep; mature color brown, reddish brown to black; distribution Trans-Mexican Volcanic Belt to high mountains in southern Honduras..................... planirostris ( Chapuis, 1869)

- Dorsal surfaces lustrous to semi lustrous; pronotal interspaces smooth, punctures shallow; mature color reddish-brown to deep dark-reddish brown; distribution Alaska to New Mexico...................................................... 4

4 (3) Pronotum interspaces distinctly reticulate ( Fig. 16 a), large punctures less than twice the diameter of small; declivital interstriae granules evenly separated, declivital granules vested with a long, hair-like setae; averaging shorter (4.2 mm); distribution coastal from Alaska to southern California......................................... rugipennis ( Mannerheim, 1843)

- Pronotum interspaces smooth to granulate ( Fig. 16 b), large punctures more than double the diameter of small; several declivital interstriae granules absent or very small, declivital granules vested with a short, hair-like setae; averaging longer (4.6 mm); distribution transcontinental, from northern British Columbia to Nova Scotia south to Arizona and North Carolina............................................................................................. pinifex ( Fitch, 1858)

5 (1) Pronotum with distinct, long, erect, hair-like setae........................................................... 6

- Pronotum with indistinct, short, recumbent hair-like setae.................................................... 7

6 (5) Pronotum base nearly as wide as body, diameter of large punctures only twice diameter of smaller middle line not raised; hairlike setae yellow to reddish-yellow; distribution Arizona and New Mexico to northern Honduras and El Salvador....................................................................................... incomptus ( Blandford, 1897)

- Pronotum base distinctly narrower than body, diameter of large punctures more than twice diameter of smaller, middle line raised; hair-like setae whitish; distribution Central Mexico............................. longipennis ( Blandford, 1896)

7 (5) Pronotum with abundant, similar sized punctures, large less than twice diameter of small punctures; ventral vestiture short...................................................................................... knausi Swaine, 1917

- Pronotum with few, differently sized punctures, large twice diameter of small; ventral vestiture long................... 8

8 (7) Elytral surfaces dull, entirely, distinctly reticulate, visible at 30 × magnification; pronotum longer (1.07 ± 0.03); body length averaging longer (4.5 mm)............................................................ reticulatus Wood, 1971

- Elytral surfaces smooth and glossy, varying from granulate to reticulate on basal third of elytra; pronotum shorter (1.03 ± 0.04); body length averaging shorter (4.0 mm)........................................... porosus ( LeConte, 1868)

Figures

FIGURE 14. Hylurgops, prothorax proportion and shape: a) wider than long and constricted anteriorly (H. planirostris), b) longer than wide and smoothly tapering anteriorly (H. knausi).

FIGURE 15. Elytral declivities of New World Hylurgops: a) H. palliatus, b) H. planirostris, c) H. rugipennis, d) H. pinifex, e) H. incomptus, f) H. longipennis, g) H. knausi, h) H. reticulatus, and i) H. porosus.

FIGURE 16. Prothoracic discal surfaces of Hylurgops rugipennis and the eastern form of H. pinifex: a) reticulate and dull, sometimes shiny with similarly-sized punctures (H. rugipennis), b) shiny (eastern form), subgranulate (western form) with distinct, differently-sized punctures (H. pinifex).