Fornax dixiensis, , Otto, 2017

Otto, Robert L., 2017, Descriptions of six new species of false click beetles (Coleoptera: Eucnemidae: Macraulacinae), with new identification keys for one tribe and two genera, Insecta Mundi 2017 (558), pp. 1-19 : 3-4

Fornax dixiensis sp. nov.

Fig. 1–3

Diagnosis. Form of the pronotum, along with produced last abdominal ventrite will distinguish the new species from both Fornax bicolor (Melsheimer) and Fornax knulli Muona in the United States.

Description. Female holotype: Length 11.0 mm. Width, 3.0 mm. Body subcylindrical, elongate; uniformly brownish-black; scape dark brownish-black, pedicel and antennomeres III–XI dark brown; legs including tarsi dark brown; head, pronotum and elytra clothed with short, recumbent yellowish setae ( Fig. 1 ).

Head: Surface rugose, shiny, subspherical; frons convex, without median carina or fovea above frontoclypeal region; apical margin of frontoclypeal region rounded, about 2 times wider than base; mandibles stout, bidentate, densely punctate.

Antenna: Filiform from antennomeres III–XI, attaining nearly 1/2 the length of the body; antennomere III slightly longer than IV; antennomeres IV–X each sub-equal, longer than wide; antennomere XI slightly longer than X.

Pronotum ( Fig. 2 ): Surface shiny, densely rugose to granulate; slightly longer than wide, with moderate, sharp hind angles; lateral sides widest at the middle, strongly narrowing towards head; disc convex with shallow median groove, without circular fovea; base sinuous, with pair of circular depressions above scutellum.

Scutellum: Elongate, sub-triangular, shallowly punctate and distally rounded.

Elytra: Distinctly striate, deepest at humeral region; interstices slightly elevated; surfaces shiny with dense, crowded punctures.

Legs: First tarsomere as long as the combined lengths of the remaining four on mesothoracic tarsi; tibiae rounded in cross section; metathoracic tarsomeres I–III simple; metathoracic tarsomere IV excavated; mesothoracic tarsomere V elongate with basally toothed claws.

Venter ( Fig. 3 ): Closely punctate, with elongate, recumbent whitish setae; hypomeron with basally open, lateral antennal grooves; metathoracic episterna parallel-sided; elytral epipleura shiny, grooved throughout, without punctures; metathoracic coxal plates medially more than 6.0 times wider than laterally.

Variation. Three female paratypes were examined. Female paratypes measured 11.0–12.0 mm long and 3.0 mm wide. Two of the three paratypes are slightly longer than the holotype. One paratype is as long as the holotype. All paratypes are as wide as the holotype. There are no exoskeletal difference between these paratypes and the holotype.

Type Material. Holotype, ♀: “ Florida: Highlands Co., Highlands Hammock, State Park , 16-V-2011, Collector: M.L. Payne, Purple Prism trap, w/ Manuka/phoebe oil” / “ Fornax , sp., Det. R.L. Otto, 2014” / “ HOLOTYPE:, Fornax , dixiensis, Otto , det. R.L. Otto, 2016 ” (♀ handwritten behind species name on label) [red printed label] . Holotype deposited in FSCA .

Paratypes. 3 ♀♀: FLORIDA: 1♀, “ FLORIDA: Highlands Co., Highlands Hammock St. pk., 8-V-2009, D. Harris, lindgren funnel trap ” / “ PARATYPE:, Fornax , dixiensis, Otto , det. R.L. Otto, 2016 ” (♀ handwritten behind species name on label) [yellow printed label] ; 2♀♀, “ Florida: Highlands Co., Highlands Hammock, State Park , 16-V-2011, Collector: M.L. Payne, Purple Prism trap, w/ Manuka/phoebe oil” / “ PARATYPE:, Fornax , dixiensis, Otto , det. R.L. Otto, 2016 ” (♀ handwritten behind species name on label) [yellow printed label] . Paratypes are deposited in FSCA and GERP.

Distribution. The eucnemid species is known from four specimens taken from a state park in south central Florida.

Biology. Three specimens were taken from a purple prism trap (Synergy Semiochemicals, British Columbia) baited with Manuka oil and Phoebe oil. One specimen was taken from a Lindgren funnel trap. Larvae and pupae are unknown.

Etymology. Specific epithet is derived from a combination of two words, ‘dixie’, a regional nickname given to the southern United States and ‘-ensis’, a Latin adjectival suffix meaning “pertaining to”; from which the new species has been taken.

Remarks. Fornax dixiensis is a highly distinctive species recently discovered in the United States. The new species can be readily separated from both F. bicolor and F. knulli based on the form of the pronotum and last visible ventrite of the abdomen. Lateral sides of the pronotum is widest at the middle before narrowing anteriorly in the new species, arcuate in the other two species. Secondly, the last visible ventrite is moderately to strongly produced in the new species and obtuse in the other two species. The new species is more closely related to a number of Neotropical species of Fornax distributed in Central and South America, which possess a strongly produced last visible ventrite. The new species is very similar in appearance to the Central American Fornax truncatus Horn ( Fig. 4 ). The new species differs from F. truncatus based on the exoskeletal surfaces of the pronotal disc. The pronotal surface is smooth with widely spaced punctures in F. truncatus and rugose with closely spaced punctures in F. dixiensis .

Figures

Figures 1–4. Fornax species.1) Fornax dixiensis female holotype (FSCA), dorsal habitus. 2) Fornax dixiensis female holotype (FSCA), head/pronotum, dorsal habitus. 3) Fornax dixiensis female holotype (FSCA), lateral habitus. 4) Fornax truncatus female syntype (BMNH), dorsal habitus. (Scale: 1–3 = 1.0 mm; 4 = 5.0 mm.)