Dyscolotaxia hispaniolensis Otto, 2023

Otto, Robert L., 2023, A revision of Dyscolotaxia Horn, 1890 (Coleoptera: Eucnemidae: Macraulacinae: Macraulacini), with the description of Amazotaxia new genus from South America, Insecta Mundi 2023 (21), pp. 1-15 : 8-9

Dyscolotaxia hispaniolensis Otto , new species

Fig. 14–18

Differential diagnosis. The strongly produced last abdominal ventrite along with an Antillean distribution will distinguish this new species from all known Dyscolotaxia species.

Type material. Male holotype: “DOMINICAN REP: Prov.; Barahona , nr. Filipinas; Larimar Mine; 26-VI –7-; VIII-1992: R. Woodruff; Skelley; window trap ” / “ Dyscolotaxia ; Det.; P.J. Johnson 1997” (black framed white label; “ Dyscolotaxia ” and “97” handwritten on label) / “ HOLOTYPE:; Dyscolotaxia ; hispaniolensis ♂; Otto; Det. R.L. Otto; 2021” (red printed label). Holotype is deposited in FSCA.

Paratype. 1 ♂: DOMINICAN REPUBLIC: “DOMINICAN REP: Prov.; Barahona, nr. Filipinas; Larimar Mine ; 26-VI –7-; VIII-1992: R. Woodruff; Skelley, window trap ” / “ PARATYPE:; Dyscolotaxia ; hispaniolensis ♂; Otto; Det. R.L. Otto; 2021” (yellow printed label) ( FSCA) . Paratype is deposited in FSCA.

Description. Male holotype: Length, 6.0 mm. Width, 1.75 mm. Body elongate; uniformly black; scape and flagellomeres VI–IX brown-black, pedicel and flagellomeres I–V dark reddish brown; femur and tibiae blackish; tarsi dark brown; head, pronotum, and elytra clothed with short, recumbent, yellowish setae ( Fig. 14 ). Head: Subspherical, without indication of median carina on frons above antennal insertions; surface shiny, punctures somewhat deep, closely dispersed; apical margin of frontoclypeal region feebly trilobed, more than 2 times wider than base; interantennal carina present at base of frontoclypeal region; mandibles stout, bidentate, densely punctate. Antennae ( Fig. 15 ): Capitate with flagellomeres VI–IX forming an elongate club, reaching slightly beyond half the length of the body; with last 3 segments extending beyond pronotal hind angles; flagellomere I elongate, about twice as long as II; flagellomeres II and III subequal, quadrate, each slightly shorter than IV; flagellomeres IV and V subequal, quadrate; flagellomeres VI–VIII subequal, each longer than wide and as long as flagellomeres III–V combined; flagellomere IX slightly longer than VIII. Pronotum: Surface shiny; punctures somewhat deep, closely spaced; slightly longer than wide, with well developed hind angles; lateral sides arcuate and narrowed craniad; disc convex without depressions or carinae; base sinuous. Scutellar shield: Triangular shaped, longer than wide, punctate, setose, and distally rounded. Elytra: Striae indicated as solid lines; interstices flattened; surfaces shiny, very closely and shallowly punctate. Legs: First tarsomere as long as combined length of remaining four on mesothoracic and metathoracic tarsi; tibiae rounded in cross section; lateral surface of mesothoracic and metathoracic tibiae with setae and transverse rows of spine combs; metathoracic tarsomeres I–III simple; metathoracic tarsomere IV excavate, as wide as III; metathoracic tarsomere V short; pretarsal claws simple. Venter ( Fig. 16 ): Punctures somewhat deep, very closely dispersed; surface with recumbent, yellowish setae; hypomeron with basally opened, lateral antennal grooves; metathoracic episterna parallel sided; elytral epipleura simple, punctate; metathoracic coxal plates medially 3.0–6.0 times wider than laterally; last abdominal ventrite apically produced.

Sexual dimorphism. Females are unknown.

Aedeagus (paratype) ( Fig. 17–18 ). Basal piece longer than wide, laterally parallel sided, dorsally opened, apically rounded; remaining parts elongate, apically narrow, constricted laterally above attachment point of median lobe; parameres elongate, apically rounded, each without lateral tooth; median lobe elongate and basally broad, strongly narrowed halfway, apically pointed, bifid, and much longer than parameres.

Variations. One male paratype examined. Paratype measured 5.75 mm long and 1.75 mm wide. Paratype slightly shorter than and as wide as the holotype. Femur and tibiae dark brown, slightly lighter in color compared to the holotype. No other additional exoskeletal differences observed between the paratype and the holotype.

Distribution. This new Antillean eucnemid is an endemic species on the island of Hispaniola, in the Dominican Republic.

Biology. Two adults were taken from a window trap. Larvae and pupae are unknown.

Etymology. The specific epithet is derived from a combination of two words, ‘Hispaniola’, the name of the island of origin and ‘-ensis’, a Latin adjectival suffix meaning “pertaining to”, from which the new species has been taken.

Figures

Figures 14–18. Dyscolotaxia hispaniolensis Otto sp. nov., holotype (FSCA). 14) Dorsal habitus. 15) Antenna. 16) Ventral habitus. 17) Male paratype (FSCA), aedeagus, dorsal view. 18) Male paratype (FSCA), aedeagus, lateral view. (Scale: 15, 17–18 = 0.5 mm; 14, 16 = 1.0 mm)