Dromaeolus brunneus Otto, Muona and Córdoba-Alfaro, 2023

Otto, Robert L., Muona, Jyrki & Córdoba-Alfaro, Jim, 2023, A new genus and sixteen new species of false click beetles (Coleoptera: Eucnemidae) described from the Heredia Province of Costa Rica with several additional records from the Osa Peninsula and Panama, Insecta Mundi 2023 (991), pp. 1-36 : 25-27

Dromaeolus brunneus Otto, Muona and Córdoba-Alfaro , new species

Figures 56–58

Diagnosis. The new eucnemid species can be readily distinguished by its elongate form, brown colored dorsum and presence of interantennal carina from any Dromaeolus species present in Costa Rica. The new species is very similar to the Nearctic D. badius (Melsheimer) and D. salsus Bonvouloir. The presence of an interantennal carina and shorter flagellomere II will distinguish the new species from either Nearctic species.

Type material. Male holotype: “ COSTA RICA: Heredia; Est.Bio. La Selva, 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/01/208; 16 Septembre 1993; Parcelas sucesionales” / “ HOLOTYPE:; Dromaeolus ; brunneus ♂; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (red printed label). Female allotype: “ COSTA RICA: Heredia; Est.Bio. La Selva , 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/10/380; 15 Marzo 1994; Bosque primario” / “ ALLOTYPE:; Dromaeolus ; brunneus ♀; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (yellow printed label). Holotype and allotype are to be deposited in INBC .

Paratypes. 3 ♂♂ 8 ♀♀: COSTA RICA: 1 ♀, “COSTA RICA: Heredia; Est.Bio. La Selva , 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/13/028; 03 Marzo 1993; Bosque secundario” / “ PARATYPE:; Dromaeolus ; brunneus ♀; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (yellow printed label) ( INBC) ; 1 ♀, “COSTA RICA: Heredia; Est.Bio. La Selva, 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/10/025; 03 Marzo 1993; Bosque primario” / “ PARATYPE:; Dromaeolus ; brunneus ♀; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (yellow printed label) ( INBC) ; 1 ♀, “COSTA RICA: Heredia; Pr: La Selva Bio. Sta. ; 3 km S Pto. Viejo; 10°26′N 84°01′W ” / “ 1 Abril 1993; Bosque secundario; M/02/049” / “ PARATYPE:; Dromaeolus ; brunneus ♀; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (yellow printed label) ( INBC) ; 1 ♂, 1 ♀, “COSTA RICA: Heredia; Est.Bio. La Selva, 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/16/063; 02 Abril 1993; Bosque secundario” / “ PARATYPE:; Dromaeolus ; brunneus ; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (either ♂ or ♀ typed behind species name on label) [yellow printed label] (2, INBC) ; 1 ♂, “COSTA RICA: Heredia; Est.Bio. La Selva, 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/04/067; 15 Abril 1993; Bosque primario” / “ PARATYPE:; Dromaeolus ; brunneus ♂; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (yellow printed label) ( INBC) ; 1 ♀, “COSTA RICA: Heredia; Est.Bio. La Selva , 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/10/104; 18 Mayo 1993; Bosque primario” / “Collection of the Global; Eucnemid Research Project; (Robert L. Otto)” (green framed white label) / “ PARATYPE:; Dromaeolus ; brunneus ♀; Otto , Muona & Córdoba-Alfaro ; Det. R. L. Otto ; 2019” (yellow printed label) ( GERP); 1 ♀, “COSTA RICA: Heredia; Est.Bio. La Selva, 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/04/111; 01 Junio 1993; Bosque primario” / “ PARATYPE:; Dromaeolus ; brunneus ♀; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (yellow printed label) ( INBC) ; 1 ♂, “COSTA RICA: Heredia; Est.Bio. La Selva, 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/11/389; 04 Abril 1994; Bosque secundario” / “ PARATYPE:; Dromaeolus ; brunneus ♂; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (yellow printed label) ( INBC) ; 1 ♀, “COSTA RICA: Heredia; Est.Bio. La Selva, 50–; 150 m 10°26′N 84°01′W; Proy. ALAS, INBio-OET” / “M/10/635; 02 Mayo 1996; Bosque primario” / “ PARATYPE:; Dromaeolus ; brunneus ♀; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (yellow printed label) ( INBC) ; 1 ♀, “COSTA RICA: Heredia; Est.Bio. La Selva , 50–; 150 m 10°26′N 84°01′W; Apr. 2000, INBio-OET” / “ 17 Abril 2000; Bosque secundario; M/19/746” / “ PARATYPE:; Dromaeolus ; brunneus ♀; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (yellow printed label) ( INBC) . Paratypes are to be deposited in INBC and GERP.

Description. Male holotype: Length, 6.0 mm. Width, 1.5 mm. Body elongate; dark brown; antennae and legs dark reddish-brown; head, pronotum and elytra clothed with short, recumbent yellowish setae ( Figure 56 ). Head: Surface dullish, subspherical, closely punctate; frons convex, simple without impression or carina; apical margin of frontoclypeal region weakly trilobed, about 2 times wider than base; interantennal carina complete; mandibles stout, bidentate, densely punctate. Antenna: Filiform from flagellomeres I–IX, attaining up to 1/3the length of the body, just beyond pronotal hind angles; flagellomere I longer than wide, longer than II; flagellomeres II–III each sub-equal, longer than wide, shorter than IV; IV–VIII each longer than wide, sub-equal; flagellomere IX slightly longer than VIII. Pronotum: Surface somewhat dullish, with closely spaced punctures; longer than wide, with well-developed, sharp hind angles; sides arcuate; disc convex without fovea or carina; base sinuous. Scutellar shield: Longer than wide, sub-triangular, shallowly punctate, setose and distally rounded. Elytra: Very shallow striae indicated at humeri region, indistinct elsewhere; interstices flattened; surfaces shiny, transversely rugose at basal 1/2, closely punctate at apical 1/2. Legs: First tarsomere as long as the combined lengths of the remaining four on meso- and metatarsi; tibiae rounded in cross section; metatarsomeres I–III simple; metatarsomere IV excavated; metatarsomere V elongate with simple claws. Venter ( Figure 57 ): Closely punctate, with short, recumbent yellowish setae; hypomeron with basally opened, lateral antennal grooves; metepisterna parallel-sided; elytral epipleura punctate; metacoxal plates medially 3.0–6.0 times wider than laterally.

Female allotype ( Figure 58 ): Length, 9.0 mm. Width, 2.0 mm. Short carina extending from interantennal carina down the frontoclypeal region. Flagellomeres filiform, less than 1/3 the length of the body; flagellomere I longer than wide, longer than II; flagellomere II longer than wide, as long as III; flagellomeres IV–VIII longer than wide, sub-equal.

Variations. Three male and eight female paratypes were examined. Males measured 6.0 mm long and 1.5 mm wide. Females measured 6.0–9.0 mm long and 1.5–2.5 mm wide. All male paratypes are just as long as and as wide as the holotype. Two female paratypes are just as large and as wide as the allotype. Four female paratypes are shorter than and just as wide as the allotype. The remaining two female paratypes are shorter than and narrower than the allotype. None of the paratype have a short carina extending down the frontoclypeal region from the interantennal carina. Four paratypes out of 11 have the same elytral microsculpture as the holotype. The remaining seven paratypes exhibit transversely rugose surfaces at the basal 1/3of the elytra instead of the basal 1/2.

Distribution. This eucnemid species is known from 13 specimens taken from La Selva within the province of Heredia.

Biology. Six specimens were taken from a primary forest. Six specimens were taken from a second growth forest. One specimen was taken from a successional parcel. Larvae and pupae are unknown.

Etymology. The specific epithet is named from its brown colored dorsum present on the new species.

Figures

Figures 54–57. Costa Rican Dromaeolus species. 54) Dromaeolus americanus sp. nov., dorsal habitus. 55) Dromaeolus americanus sp. nov., ventral habitus. 56) Dromaeolus brunneus sp. nov., male holotype, dorsal habitus. 57) Dromaeolus brunneus sp. nov., male holotype, ventral habitus. (Scale: 54–57 = 1.0 mm)

Figures 58–62. Costa Rican Dromaeolus species. 58) Dromaeolus brunneus sp. nov., female allotype, dorsal habitus. 59) Dromaeolus herediensis sp. nov., dorsal habitus. 60) Dromaeolus herediensis sp. nov., ventral habitus. 61) Dromaeolus holdridgei sp. nov., dorsal habitus. 62) Dromaeolus holdridgei sp. nov., ventral habitus. (Scale: 59–62 = 1.0 mm; 58 = 5.0 mm)