Ptenidium (Peruvium) triangulum, Darby, 2020

Darby, Michael, 2020, Eight new species of Ptenidiini and Discheramocephalini (Coleoptera: Ptiliidae) from Ecuador, European Journal of Taxonomy 599, pp. 1-19 : 8-9

Ptenidium (Peruvium) triangulum sp. nov.

urn:lsid:zoobank.org:act:D49B2C8D-87D8-4E05-84A2-F2EB3F324A2C

Fig. 4 A–E

Etymology

Named after the shape of the proventral intercoxal process.

Material examined

Holotype

ECUADOR • ♂; Napo, Cosanga , Camp D Mel; 2100 m a.s.l.; 3 Mar. 2018; dead leaves from crown of felled tree in family Melastomataceae ; J. McClarin leg.; QCAZM.

Description

SIZE. Habitus length 0.97 mm ( Fig. 4A ).

COLOUR. Dark brown/black, dorsum finely punctured throughout with very short pubescence, legs and antennae yellow/brown.

HEAD. With shallow point medially on disc near anterior margin, width across eyes 0.28 mm; antennomeres III–XI length 0.31 mm; mentum chaetotaxy of usual Ptenidium type, sides strongly rounded to anterior margin, prementum with 5–6 setae.

PRONOTUM. Length 0.27 mm, width 0.44 mm, broad, widest before strongly rounded hind angles, without setae in lateral margins and foveae on anterior and posterior margins, posterior margin strongly sinuate at lateral angles, with tufts of setae ( Fig. 4C ).

ELYTRA. Length 0.55 mm, width 0.47 mm, shallowly rounded, widest just anterior to middle.

SCUTELLUM. Small, triangular, with very small median keel on anterior margin.

PROSTERNUM. Very narrow in front of procoxae, which are separated by an elongate, triangularly shaped keel ( Fig. 4E ).

MESOVENTRITE. Reticulate, collar extending narrowly onto humeri, forming blunt teeth, medially with three extensions onto mid-keel, which is setose at margins; keel of usual Ptenidium type, with two long setae at base and setose lateral arms extending posteriad to join margins of mesocoxal cavities, mesocoxae not adjacent; mesoventrite posterior margin shallowly curved to lateral margins ( Fig. 4 D–E).

METAVENTRITE. Length 0.19 mm, width 0.46 mm, sparsely pubescent but thickened medially at rear margin, distance between metacoxae 0.13 mm, mesocoxal cavities narrowly bordered, metepisternal sutures not visible.

MALE GENITALIA. Aedeagus ( Fig. 4 Ba–Bb).

FEMALE GENITALIA. Not known.

Remarks

Description on the basis of a single specimen is considered justified by the triangular shape of the procoxal process, which is different from that in all other species in the subgenus Peruvium described to date.

Figures

Fig. 4. Ptenidium triangulum sp. nov. A. Habitus. B. Dorsal (Ba) and lateral (Bb) views of aedeagus. C. Tuft of setae at the posterior angle of the pronotum ×1200. D. Venter ×335. E. Pro- and mesoventra, showing keels between the pro- and mesocoxae ×675.