Dromaeolus argenteus Otto, 2023

Otto, Robert L., 2023, The false click beetles (Coleoptera: Elateroidea: Eucnemidae) of the Dominican Republic. Part I: A look into the past, Insecta Mundi 2023 (973), pp. 1-23 : 18

Dromaeolus argenteus Otto , new species

Fig. 22–23

Holotype. Embedded in ovoid Dominican Republic amber piece, 15 mm × 9 mm × 4 mm. Amber piece is clear yellow with several air bubbles and micro fractures.

Diagnosis. Metallic silver luster on the surface, along with form and lateral pronotal ridge will distinguish this species from all other Caribbean Dromaeolus .

Description. Length, 4.0 mm. Width, 1.0 mm. Habitus subcylindrical, slightly wide, moderately elongate and tapering towards the elytral apex; metallic silver luster on all surfaces; head, pronotum and elytra clothed with inconspicuous, sparse, recumbent setae ( Fig. 22 ). Head: Closely, deeply punctate to rugose, subspherical with convex frons; surfaces shiny; apical margin of frontoclypeal region very weakly trilobed, about 2.5 times wider than base; mandibles stout, bidentate, densely punctate. Antennae: Serrate, reaching about one-third the length of the body, up to hind angles of pronotum; flagellomere I longer than II; flagellomere II as long as the pedicel, shorter than III; flagellomeres III–VII each slightly longer than wide, sub-equal; flagellomere IX longer than VIII. Pronotum: Closely, deeply punctate to rugose; surface shiny; slightly longer than wide, with short hind angles; basal half parallel-sided; anterior half slightly arcuate; disc simple; base with short, median impressed line above scutellum; hypomeron with basally closed lateral antennal grooves. Scutellum: Shallowly punctate, oblong, triangular and distally rounded. Elytra: Shallow striae present; interstices slightly elevated, very closely punctate to transversely rugose. Legs: First tarsomere as long as 2–5 combined on mesothoracic and metathoracic tarsi; tibiae rounded in cross section; metatarsomeres I–III simple; metatarsomere IV excavate-emarginated; metatarsomere V elongate with simple claws. Venter ( Fig. 23 ): Punctate, with sparse, recumbent yellow setae; metepisternum parallel-sided; metacoxal plates medially 3.5 times wider than laterally.

Etymology. Specific epithet is derived from the French term Argent which means “silver” for its metallic silver luster present on the exoskeletal surface as a result of its entombment in amber.

Figures

Figures 19–23. Dominican amber Eucnemidae. 19) Fornax dominicensis Otto sp. nov., lateral view. 20) Fornax serropalpoides Otto sp. nov., dorsal view. 21) Fornax serropalpoides Otto sp. nov., ventrolateral view. 22) Dromaeolus argenteus Otto sp. nov., dorsolateral view. 23) Dromaeolus argenteus Otto sp. nov., ventrolateral view. (Scale: 19–23 = 2.0 mm).