Deltochilum quasistriatum González-Alvarado & Vaz-De 2021, sp. nov.

Deltochilum quasistriatum sp. nov.

urn: lsid:zoobank.org:act: E7290E3C-1482-481C-AAAC-E0C44D7432DE

Figs 1D, 2D, 3D, 4D, 5D, 6D, 7D, 8D, 10

Diagnosis

Close to D. tenuistriatum sp. nov. by having striae I–VII conspicuous (Figs 1D–E, 4D–E), but III–VII successively thinner and more ill-defined and the pronotal disc with irregular shiny points contiguous with punctures (Fig. 3D–E). However, it can be distinguished by having the first stria wider than second, largest interstrial punctures (Fig. 4D) and by the pygidial punctures which are largest and densest (Fig. 5D).

Etymology

From latin quasi - 'almost' + stria in reference to the ill-defined striae.

Type material

Holotype GUYANA • 1 ♂; Mazaruni-Potaro District, Takutu Mountains; 6°15′ N, 59°5′ W; 18 Dec. 1983; P.D. Perkins and W.E. Steiner leg.; window trap, mountain rainforest, near logging area; EARTHWATCH Research Expedition; [aedeagus and endophallus extracted]; CMNEN WSD00041744.

Description

MEASUREMENTS AND COLOR. Holotype male, length 8.1 mm, humeral width 5.1 mm. Dark green with red reflections on pronotum, elytra dark brown with some red reflections (Fig. 1D). Dark brown ventrally, with few shiny red reflections on ventrite VI and meso- and meta-legs light brown (Fig. 6D).

HEAD (Fig. 2D). Dorsal inter-ocular distance approximately seven times width of one eye. Punctures on frons separated by less than one diameter of each puncture, almost contiguous. Punctures on head disc separated by one diameter of each puncture.

PRONOTUM (Fig. 3D). Medial angle projected. Punctures on the disc separated by less than one diameter, almost contiguous. Shiny points on disc irregular and contiguous to punctures.

ELYTRA (Figs 1D, 4D). Carina of ninth interstria reaching middle of elytral length. Punctures on first stria subequal in size to second stria, but denser. Striae I–VII conspicuous. First stria slightly wider than second stria. Striae III–VII narrow and ill-defined, successively narrower and more ill-defined, with VII almost inconspicuous. Width third stria approximately 1/40 th of distance between striae II and III. Stria VIII conspicuous only laterally, discontinuous in some parts and reaching apex of carina of the ninth interstria. Punctures of second and third interstriae on disc separated by less than one diameter. Punctures of third interstria on disc occupying about 1/10 th of the distance between striae II and III. Apical tubercles on interstriae III, V–VII (Fig. 5D).

ABDOMEN (Fig. 6D). Width of expansion of the ventrite I, on ventrite III, subequal to distance between clypeal teeth; expansion reaching middle of ventrite IV. Margins of expansion between ventrites II–IV forming an acute angle. Apex of expansion truncate. Basal area of expansion with punctures separated by less than one diameter, almost contiguous.

LEGS. Apex of mesotibia on ventral-internal margin with a small spatulate expansion. Expansion of metafemur 1.8 × wider than the width of metafemur basal to expansion. Internal margin of metatibia with large tubercles, occupying almost all metatibial length.

PYGIDIUM (Fig. 5D). Most of the punctures separated by less than one diameter; punctures basally denser than punctures on disc; basal punctures almost contiguous. Discal punctures occupying approximately 1/29 th the width on middle of pygidium.

GENITALIA (Figs 7D, 8D). Aedeagus as described in the gilli species group. Medial endophallite sinuate. Sub-medial area of endophallus with scales.

Remarks

This species is only known from the holotype.

Known distribution

Guyana. Cuyuni-mazaruni, Takutu Mountains (Fig. 10, green triangle).