Dinoxyleborus infernus, Smith, 2017

Smith, Sarah M., 2017, Dinoxyleborus Smith, a new genus of Neotropical xyleborine ambrosia beetle (Coleoptera, Curculionidae: Scolytinae), Zootaxa 4303 (1), pp. 131-139 : 135-136

Dinoxyleborus infernus sp. nov.

(Figs 7–10)

Type material. Holotype, female, SURINAME, [Para], Jodensavane, Kamp 8, 1961, Lichtv., #765, Schulz , ex. light trap ( NMNH).

Description. Female. Length 2.2 mm and 3.1 times as long as wide. Body color light brown apically and transitioning to dark red brown posteriorly with the elytral declivity and spines the darkest. Legs and antennae light brown. It is possible that the type is teneral and the mature color similar to that of other Dinoxyleborus species.

Head. Frons slightly convex from epistoma to upper level of eyes; surface shagreened, dull, punctate. Eyes moderately emarginated above level of antennal insertion. Scape narrow, elongate, about 3/4 length of club. Antennal funicle four segmented, segments equal in size. Pedicle longer than funicle. Club approximately circular, club type 4 ( Hulcr et al. 2007), flattened, round; segments 1 and 2 strongly procurved, corneus, segment 3 slightly procurved, corneous, visible on both sides of club.

Pronotum. Pronotum prolonged posteriorly (Type 8a, Hulcr et al. 2007), 1.1 times as long as wide. Anterior margin basic, elongate, parallel-sided, rounded when viewed dorsally (Type 9, Hulcr et al. 2007), lacking a row of serrations. Surface shagreened, anterior third finely asperate, asperities close, arranged in concentric rings in anterior and anteriolateral areas; disc finely and evenly punctate. Lateral margins rounded, slightly carinate on basal quarter. Base transverse.

Legs. Protibia slender, broadest at apical third, posterior face inflated, tuberculate; three small denticles present on outer margin of apical third. Meso- and metatibia with evenly rounded outer margin, flattened, posterior face unarmed. Mesotibia armed with 6 socketed denticles on outer margin.

Elytra. 2.0 times as long as wide. Elytral base transverse, humeral angles rounded. Scutellum small, triangular, flat, flush with elytra. Sides straight from base to declivity midpoint; apex entire. Disc longer than declivity. Disc smooth, shining, finely punctate; each interstrial puncture bearing a single erect, fine, golden, hair-like seta 1.5–2.0 times the length between punctures (may be abraded); interstriae equal to width of striae. Interstriae parallel on disc and broadened towards elytral apex. Declivity deeply concave, separated from disc by large elevated sulcus bearing denticles and spines. Declivital face densely shagreened, opaque, sparsely, shallowly punctate, setose on basal half; setae short, erect, fine, golden, hair-like. Declivital margin armed by four spines, three denticles and abundantly ornamented with long semi-recumbent setae; spines roughly similar in size. Two denticles at base, separated from spine 1 by length greater than that of spine 1, on interstriae 1. Single large denticle ventrad to spine 1, between spines 1 and 2, on interstriae 4. Spine 1 originating at basal third, on interstriae 3, 1.5 times as long as basal width, apex acute. Spine 2 dorsal of spine 3, touching its base, originating on basal third, on interstriae 5, 1.5 times as long as basal width, apex acute; spines 2 and 3 may be connected by a tumescence. Spine 3 at basal third, on interstriae 6, as long as basal width, thick, apex acute, touching bases of spines 2 and 4. Spine 4 at apical margin, on interstriae 7, 1.5 times as long as basal width, thick, apex blunt. Area dorsal of declivital margin on interstriae 3 armed with several minute denticles. Declivital interstriae armed with granules dorsad to the margin of the sulcate area.

Diagnosis. Dinoxyleborus infernus can be distinguished from all other species by having four equally sized spines on the declivity.

Etymology. Infernus = (L.) hellish. In reference to the menacing appearance of the species’ declivity ornamented with numerous spines and denticles.

Distribution: Suriname (Para).

Comments. The type specimen is card mounted with an excessive amount of what presumably is shellac. All features from the ventral side, parts of the head and legs were unable to be examined and are thus missing from the description.

The holotype of D. infernus was incorrectly identified by Wood (2007: 367) as a specimen of Premnobius sexnotatus (Schedl) , now Dinoxyleborus .

PLATE 3. Dinoxyleborus infernus sp. nov. female. Figure 7. Dorsal view. 8. Lateral view. 9. Frontal view. 10. Declivity.