Jansonia anceps ( Janson, 1875 )

Ratcliffe, Brett C., 2014, A Review of the Neotropical GeneraAstroscaraSchürhoff, 1937, ChiriquibiaBates, 1889, HadrostictaKraatz, 1892, JansoniaSchürhoff, 1937, MacrocraniusSchürhoff, 1935, andTiaroceraBurmeister, 1842 (Coleoptera: Scarabaeidae: Cetoniinae: Gymnetini), The Coleopterists Bulletin 68 (3), pp. 363-376 : 370-371

Jansonia anceps ( Janson, 1875) ( Figs. 16–20 )

Gymnetis anceps Janson 1875: 373 (original combination). Holotype and allotype at MNHN, examined. Type locality “Cayenne” (probably erroneous).

Description. Length 16.8–21.2 mm; width across humeri 10.8–11.6 mm. Color of dorsum opaque black with cretaceous marks (with small, black punctures) as follows: head with 2 longitudinal, parallel, irregular bands on apical half of frons and most of clypeus or with bands totally coalesced; pronotum with broad band on each lateral margin; elytra with broad band on each lateral margin wrapping around to apices (or reduced to sparse flecks in allotype), disc with a few, small flecks. Head: Surface of frons and clypeus with punctures moderate in size and density (denser in allotype), setigerous; setae short, moderate in density, piceous to black. Frons on each lateral margin above antennal insertion elevated. Clypeus broadly rounded on sides, apex distinctly emarginate. Eyes large, interocular width equals 3.2 transverse eye diameters. Antenna with 10 antennomeres, club subequal in length to entire stem. Pronotum: Surface with punctures moderate in size and density (allotype with punctures becoming large to rugopunctate in anterior angles). Sides with strong marginal bead for entire length. Elytra: Disc punctate-striate, punctures small. Sides on cretaceous areas with remnants of similar rows of punctures. Sutural and 2 discal costae strongly elevated, discal costae meeting at apical umbone. Apices at suture slightly, subacutely produced. Pygidium: Surface transversely rugulose at base, remainder with mostly large, transverse, crescent-shaped, setigerous punctures; setae short, piceous top black. In lateral view, profile in males weakly convex, nearly flat in females. Venter: Metasternite with large, dense, setigerous punctures either side of broadly impunctate center; setae long, moderate in density, piceous. Mesometasternal process, in lateral view, distinctly projecting, subparallel to ventral axis of body, apex narrowly rounded ( Fig. 17 ); in ventral view, mesometasternal process elongate with paralllel sides, apex evenly rounded. Abdominal ventrites with large, dense punctures; central third virtually impunctate; males with longitudinal sulcus at center, females lacking sulcus. Legs: Protibia in males slender, with only apical tooth, females with protibia tridentate. Parameres ( Figs. 19–20 ): In caudal view, form subrectangular, apices broadly rounded.

Distribution. Based upon label data, J. anceps is known from Ecuador and French Guiana. These two locations are on opposite sides of South America, and I strongly suspect one of those is incorrect. If I had to hazard a guess, I believe that the French Guiana locality is wrong given that French colleagues (Fabrice Lavalette and Julien Touroult) with extensive knowledge of the cetoniines of French Guiana have never seen this species (personal communications, November 2013), combined with the fact that the Ecuador specimens have more detailed collecting information rather than “Cayenne” for the French Guiana specimens.

Locality Records. 12 specimens from BCRC, BMNH, IRSNB, MNHN, and ZSMC. ECUADOR (5). GUAYAS (5) : Balzar Mountains . FRENCH GUIANA (4). CAYENNE (4) : No data. NO DATA (3).

Temporal Distribution. No data. All specimens known to me were collected pre-1880.

Diagnosis. Jansonia anceps is distinctive because of its elongate, parallel body shape ( Fig. 16 ) combined with the cretaceous markings on the lateral margins of the pronotum and elytra and lack of cretaceous markings on the pygidium and venter. The head lacks armature, the clypeus is emarginate at its apex, and the club of the antenna is as long as the entire stem. The mesometasternal process is, in lateral view, distinctly protuberant, subparallel to the ventral axis of body, and with the apex narrowly rounded ( Fig. 17 ). Males have a unidentate protibia, and females have a tridentate protibia.

Natural History. Nothing is known of the life history of this rare species.

Figures

Figs. 16–20. Jansonia anceps. 16) Habitus; 17–18) Lateral and ventral views, respectively, of form of mesometasternal process; 19–20) Parameres.