Cryptocanthon howdeni Cook, 2002

Cook, Joyce, 2002, A Revision Of The Neotropical Genus Cryptocanthon Balthasar (Coleoptera: Scarabaeidae: Scarabaeinae), The Coleopterists Bulletin (mo 1) 56, pp. 3-96 : 36-38

12. Cryptocanthon howdeni Cook sp.nov.

( Figs. 70–74 )

Material Examined. Fifteen specimens (8 males, 7 females).

Type Material. Holotype: ‘‘ MEXICO: Chiapas, Yerba- / buena Preserve, 2.1 km N.W. / Pueblo Nuevo, Solistahuacan / 2,100 m, 23.IX.1992, 92-114 / liquidam.for.litt’’ ( CMNC) male . Paratypes (14): same data as holotype ( CMNC) 4 males, 1 female ; same data except ‘‘cloud for. litter’’ ( CMNC) 3 males, 6 females .

Etymology. This species is named for Henry Howden, Canadian Museum of Nature, in recognition of his work on the genus Cryptocanthon .

Diagnosis. This species is distinguished by the following combination of characters: vertical surface of clypeus not foveate; pronotal hypomeron carinate; inflexed portion of elytron with basal fovea; metathoracic wings greatly reduced; male protibia bilobed on inner margin ( Fig. 70 ); pygidium with small median convexity in basal half; paramere apices rounded ( Fig. 73 ).

Description. Holotype. Male. Total length 4.0 mm; greatest width 2.4 mm. Head. Clypeus not strongly produced anteriorly ( Fig. 71 ). Clypeal teeth moderately developed, widely separated, moderately reflexed. Clypeal emargination evenly rounded; vertical surface slightly, broadly V-shaped, not foveate. Apical margin of clypeus lateral to teeth nearly straight. Disc of clypeus concave, with medium-sized punctures separated by one diameter or less. Clypeogenal suture vaguely indicated by raised area. Gena not produced, with slight angle at junction with anterior margin of clypeus; punctures irregularly spaced, shallow. Vertex with medium-sized, dense punctures. Pronotum. Convex medially, laterally explanate, shallow depressions laterally in posterior half; with shallow median longitudinal depression in posterior half. Anterior angles approximately right-angled. Sides anterior to lateral angles nearly straight; slightly rounded posterior to lateral angles. Posterior angles obtusely rounded, not incised. Pronotum densely punctate; punctures of disc small; laterally, punctures larger, annulate; setae fine, recumbent. Pronotal hypomeron convex, coarsely punctate, with posterolateral longitudinal carina curving toward posterior angle. Elytra. Transversely and longitudinally strongly convex; lateral carinae moderately elevated. Each elytron dorsally with seven striae, first six indicated by two feeble wavy lines, seventh vaguely indicated along edge of dorsal carina. Elytral intervals convex; each interval with row of closely spaced, very fine setose punctures on each side adjacent to striae; setae fine, pale, nearly recumbent. Inflexed portion of elytron moderately broad, evenly narrowed apically, with scattered, fine setose punctures and transverse wrinkles; basal fovea present; striae eight and nine absent, ten complete along margin of epipleuron.Epipleuron with scattered punctures in basal half. Wings. Metathoracic wings greatly reduced.

Venter. Prosternum with medium-sized shallow, annulate punctures. Mesosternum with shallow, annulate punctures; punctures small medially, large laterally. Meso-metasternal suture bluntly rounded. Metasternum concave medially; disc with minute punctures in anterior third, medium-sized shallow punctures posteriorly; laterally, punctures large, dense, annulate. Legs. Profemur strongly punctate ventrally. Protibia ( Fig. 70 ) with bilobed medial expansion in apical half before notch; subapical notch small but distinct. Mesofemur and metafemur with small, elongate punctures ventrally. Metatrochanter unmodified. Metatibia slightly angulate, not crenulate, with small subapical lobe on inner margin. Abdomen. Apical sternite with irregularly spaced, medium-sized, shallow punctures. Pygidium with small median convexity in basal half; with medium-sized, shallow punctures separated by about one diameter; base with median fovea. Male genitalia. Parameres ( Figs. 72–73 ) with apices rounded, not setose.

Variation. Male: total length 3.5–4.3 mm; greatest width 2.1–2.6 mm. Female: total length 3.5–4.2 mm; greatest width 2.0– 2.4 mm; clypeal teeth more strongly developed; protibiae unmodified; metasternum with slight concavity posteriorly; pygidial basal fovea poorly developed. In some specimens (both sexes) gena slightly produced anteriorly and clypeogenal suture clearly marked by fine carina.

Bionomics. This species has been collected from cloud forest litter, at 2,100 m elevation, during the month of September.

Geographic Distribution ( Fig. 74). This species is known only from the type locality in the Mexican state of Chiapas .

Figures

Figs. 70–73. Cryptocanthon howdeni. 70) left protibia, male; 71) clypeal outline; 72) aedeagus, lateral; 73) parameres, dorsal. Scale line 5 0.5 mm.