Fornax dixiensis Otto, 2017, 2016

Otto, Robert L., 2020, A review of the Nearctic species of Fornax Laporte (Coleoptera: Eucnemidae: Macraulacinae: Macraulacini) with descriptions of six new species, Insecta Mundi 2020 (818), pp. 1-26 : 12-14

Fornax dixiensis Otto, 2017

Fig. 3, 17–20

Diagnosis. Overall shape of the pronotum distinguishes female F. dixiensis from all Fornax species in the Nearctic region. Absence of horizontal interantennal carina distinguishes male F. dixiensis from both F. convexicollis new species and F. parallelicollis new species. Darker dorsum further distinguishes male F. dixiensis from F. appalachiensis new species, F. knulli , F. floridana new species and F. melsheimeri new species. Dull luster of the pronotum distinguishes the male of F. dixiensis from Fornax lucidicollis new species. Produced last abdominal ventrite further distinguishes the male of F. dixiensis from F. bicolor .

Type material. “ 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] ( FSCA) ; “ FLORIDA: Highlands Co., Highlands Hammock St. pk., 8-V-2009, D. Harris, lindgren funnel trap ” / “ PARA- TYPE:, Fornax , dixiensis, Otto, Det. R.L. Otto, 2016 ” (♀ handwritten behind species name on label) [yellow printed label] ( FSCA) ; “ 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] (1, FSCA; 1, GERP) .

Specimens Examined. Seven specimens were available for study: FLORIDA: “VERO BEACH, FL” / “W.L. BUDLINGMAYER, COLL. 12-V-64” (date handwritten) (1, FSCA); “VERO BEACH, FL” / “W.L. BUDLING- MAYER, COLL. 12-V-64 (date handwritten) / “ Fornax , bicolor, (Melsh.) , Det. Knull ‘67” (genus, species, author and year handwritten; folded) (1, FSCA); “FLA., Indian River Co., SH 512.5 mi. W. I-95, (4–8)- IV-1976, Fla. Med. Ent. Lab.” (dates, month and year handwritten) / “sorted from dusk-dawn, suction trap sample in, and near bay head, M.C. Thomas Collection” (1, FSCA); “FLA., Indian River Co., SR 512.5 mi. W. I-95, 9–12-V-1976, Fla. Med. Ent. Lab.” (1, FSCA); “ FLORIDA: DADE COUNTY, CAMP MAHACHEE, NR., MATHESON HAM- MOCK, 27-V-1983, MC THOMAS & L PARKER, BLACKLIGHT TRAP” (1, FSCA); “ FLORIDA: Alachua Co., Gainesville, Airport, 1-VI-1989, P. Skelley” (1, FSCA); “ FLORIDA: Alachua Co., Gainesville, SE Kincaid, Rd., ~ 1 mi. N. Paynes Prairie, old field/dry oak hammock, 7–27-VII-1998, B. Sutton, 6m Malaise trap” (1, FSCA).

Redescription. Female. Length 9.0–12.0 mm. Width 2.5–3.0 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. 17 ). Head: Subspherical; integument rugose, shiny; frons convex, without median carina or fovea above frontoclypeal region; apical margin of frontoclypeal region rounded, about 2 times wider than base; horizontal interantennal carina absent; mandibles stout, bidentate, densely punctate. Antenna: Filiform from antennomeres III–XI, attaining nearly 1/2 of body length; antennomere III slightly longer than IV; antennomeres IV–X subequal, longer than wide; antennomere XI slightly longer than X. Pronotum: Integument shiny, densely rugose to granulate; wider than long, with moderate, sharp hind angles; sides widest above midlength, strongly narrowing towards head; disc convex, with shallow median groove, without circular fovea; base sinuous, with pair of circular depressions above scutellar shield. Scutellar shield: Elongate, subtriangular, shallowly punctate and distally rounded. Elytra: Distinctly striate, deepest in humeral region; interstices slightly elevated; integument shiny, with dense punctures. Legs: First tarsomere as long as combined lengths of remaining four on meso- and metatarsi; tibiae rounded in cross-section; metatarsomeres I–III simple; metatarsomere IV excavated; metatarsomere V elongate, with basally toothed claws. Venter ( Fig. 18 ): Closely punctate, with elongate, recumbent whitish setae; hypomeron with basally open lateral antennal grooves; metepisterna parallel-sided; elytral epipleura shiny, grooved throughout, without punctures; metacoxal plates medially more than 6.0 times wider than laterally; last abdominal ventrite apically produced, short, wide.

Sexual dimorphism. Male ( Fig. 19 ) is similar to female, but can be distinguished by having the pronotum parallel-sided in basal 2/3, narrowing anteriorly in apical 1/3. Female pronotum is cranially wider above the midlength. The male is 10.0 mm long and 3.0 mm wide.

Aedeagus ( Fig. 20 ). Basal piece slightly longer than wide, laterally constricted midway down, narrower posteriorly, dorsally open, basally rounded; remaining parts elongate, strongly constricted laterally at base of parameres, apically lobed; median lobe short and stout, shorter than parameres, apically rounded, narrowly bifid; parameres curved, elongate, with a triangular lateral tooth near base.

Distribution. This precintive Florida species is known from four counties.

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. One specimen was taken from a suction trap in Indian River County, FL. One specimen was taken from a blacklight trap in Dade County. One specimen was taken from a 6 m Malaise trap placed in an old field/dry oak hammock. Developmental stages remain unknown.

Figures

Figures 17–20. Fornax dixiensis Otto. 17) Female, dorsal habitus. 18) Female, ventral habitus. 19) Male, dorsal habitus. 20) Male, aedeagus, dorsal view. (Scale: 17–20 = 1.0 mm.)