Puelchesia gracilis Ocampo and Smith

Ocampo, Federico C. & Smith, Andrew B. T., 2006, Puelchesia gracilis, a new genus and species of Pachydemini endemic to the Monte biogeographic province in Argentina (Coleoptera: Scarabaeidae: Melolonthinae), Zootaxa 1349, pp. 53-62 : 56-60

Puelchesia gracilis Ocampo and Smith sp. nov.

( Figs. 1–13 )

Type material. The type series consists of a holotype and 136 paratypes. Holotype male at IADIZA labeled: “ ARGENTINA: Mendoza / RP 20, 36 km W Pata Mora / S 36° 58' 20'' W 69° 06' 19'' / Jan- 7-2003, 1145 m / F. C. Ocampo, A. B. T. Smith” and “ Puelchesia gracilis / HOLOTYPE / F. C. Ocampo / and A. B. T. Smith” (red holotype label, handwritten). Seventy-eight paratypes with same label as holotype at ABTS (10), CMNC (10), CNCI (3), FCOC (12), FMNH (2), IADIZA (12), MLPA (5), MNNC (5), UNSM (15), USNM (4). One paratype at IADIZA is a DNA voucher specimen stored in 95% alcohol and preserved at -80° C. It bears the additional label “ UNSM SCARAB DNA / VOUCHER SPECIMEN / AS 118 / MAY 2003 ” (label with black double border). Thirtyfive paratypes labeled: “Malargüe: a 7 km / de Ranquil camino a / Barrancas / 24-1-79 / Sergio Roig” at FCOC (3), ABTS (2), IADIZA (25), and UNSM (5). Two paratypes at IADIZA labeled: “Malergüe: camino / a Barrancas a / 7 km de Ranquil Norte / 24-1-79 / Sergio Roig.” One paratype at IADIZA labeled: “Malargüe: Entre / Ranquil Norte y Ba- / rrancas, 27 km de Ranquil / 24-1-79. / Sergio Roig.” One paratype at IADIZA labeled: “San Rafael / 25 de Mayo / 1-ii-79 / Sergio Roig.” Four paratypes at IADIZA labeled: “Mendoza: San Rafael / 6 km N Punta del Agua / 14/XII/98 Flores /Roig” and “ 35° 28.25'S / 68° 04.32'W.” Thirteen paratypes deposited in ABTS (1), FCOC (1), UNSM (1), and IADIZA (10) labeled: “RA Mza Malargüe O de / Sierra Chachahuen / 07-1-03 S. Roig Debandi.” Two paratypes at HAHC labeled: “ ARGENTINA: Pr. / de La Pampa / Col. 25 de Mayo / 29-30.XII.1970 / A. Martínez” and “H. & A. HOWDEN / COLLECTION / Ottawa, Canada ” (white label with black border). All paratypes with a yellow paratype label: “ Puelchesia gracilis / PARATYPE / Ocampo and Smith.”

Type locality. Argentina, Mendoza, 36 km west of Pata Mora, S 36° 58’ 20” W 69° 06’ 19” ( Fig. 12 ).

Description of holotype. Male. Length 4.81 mm, width 1.93 mm. Head, pronotum, elytra, venter, and legs light brown; head and legs darker brown. Surface shiny. Head ( Figs. 3, 4 ): Surface glabrous; flat except for weak medial tubercle near frontoclypeal suture; densely punctate, punctures moderate in size (0.03–0.08 mm). Interocular width 0.26 mm. Eye canthus absent ( Figs. 3, 4 ). Frontoclypeal suture well defined, complete. Clypeus broadly rounded; surface flat, sparsely punctate; punctures moderate in size (0.03–0.08 mm) ( Fig. 3 ). Clypeal margin reflexed. Clypeal ventral surface setose, setae long. Labrum reduced, conical, setose; setae moderate in length. Labium reduced, labial palpi absent. Maxillae reduced, maxillary palpi with 4 palpomeres, palpomere 4 as long as palpomere 1–3 combined. Antennae with 8 antennomeres; antennomere 1 robust; antennomere 2 globose; antennomere 3–4 cylindrical; antennomere 5 short, wider than long; antennal club 3-segmented, segments tomentose on margins and apex ( Figs. 4, 5 ). Pronotum ( Figs. 1–3 ): Convex, wider than long at middle. Surface glabrous, sparsely punctate; punctures moderate in size (0.03–0.08 mm). Marginal bead present; anterior margin concave, with membrane; lateral margins slightly angular, setose (setae hair-like, long); posterior margin slightly sinuous. Anterior angles acute; posterior angles broadly rounded. Scutellum ( Fig. 1 ): Surface shiny, glabrous, apex rounded. Elytra ( Fig. 1, 2 ): Convex, elongate, subparallel. Surface shiny, sparsely punctate, setose; punctures moderate in size (0.03–0.08 mm); setae long, hair-like. Elytra with 9 striae; area between elytral suture and stria 1 (1st interstria) tapered at apex; stria 1 impressed; striae and interstriae punctate, setose. Elytral margins setose; setae long, hair-like. Hind wings ( Fig. 6 ): Subcostal and radial vein well sclerotized, not reaching radial sector vein at wing apex; radial sector vein forked at apex; medial vein well developed; medial loop short; cubital vein poorly sclerotized apical to medial loop connection; anal veins 1 and 2 connected. Ve n t e r: Pro- and metasternum with surface glabrous, margins setose; setae long or short. Metasternum with surface sparsely setose, outer half more densely setose; slightly concave on outer half. Three ventrites exposed medially. Penultimate ventrite broadly membranous on apical margin, sparsely setose; setae long. Legs ( Figs. 1, 2 , 7–9 ): Coxae sparsely setose, setae long. Femora with surface smooth, with fringe of setae on anterior face, sparsely setose dorsally. Protibiae with 3 teeth; basal tooth small, apical tooth longer than protibial spur; surface with two fringes of long setae ( Fig. 1 ); protibial spur slightly curved. Meso- and metatibiae with medial transverse carinae, carinae with 4–6 spine-like setae; apex semicircular, transversely truncate ( Figs. 7, 8 ). Meso- and metatibial spurs subcontiguous, medial. Metatibial tarsal insertion simple, without notch ( Fig. 9 ). Pro-, meso-, and metatarsomeres 1–4 subequal in length, tarsomere 5 1.3 times longer than 1–4 individually; apex of all tarsi with long, apical setae ( Figs. 1, 2 , 7, 8 ). Tarsal claws simple, gracile, symmetrical. Genitalia ( Figs. 10, 11 ): Parameres simple, symmetrical, elongate, gracile.

Female. Unknown.

Paratypes. Length 3.70–5.60 mm. width 1.85–2.10 mm. The paratypes do not vary significantly from the description of the holotype.

Etymology. Gracilis is Latin, meaning slender. This refers to the general form of this species.

Natural history. The bulk of the type series of this species was collected in a canyon beside a dry river bed ( Fig. 12 ). At the time these scarabs were collected, the canyon was extremely dry and it was obvious that it had not rained recently. There was very little insect activity and Puelchesia gracilis was the only species that came to our lights in any significant numbers. We used 250 watt mercury vapor bulbs at night to attract this species. We did not observe this species on any of the plants around the collecting area. Further natural history details are unknown.

Habitat and distribution ( Figs. 12 , 13 ). The Monte Central is a part of the Monte biogeographic province, which extends from La Rioja to southern Mendoza in Argentina with annual mean temperatures between 13–15°C ( Roig-Juñent & Flores 2001). The habitat where specimens of Puelchesia gracilis were collected is categorized as scrub desert. The area is dominated by vegetation communities of Larrea divaricata Cavanilles , L. cuneifolia Cavanilles (Zygophyllaceae) , Bulnesia retama (Gillies ex Hooker and Arnott) , Zuccagnia punctata Cavanilles ,, Geoffroea decorticans (Gillies ex Hooker and Arnott) (Fabaceae) , Prosopis alpataco Philippi (Mimosaceae) , and Capparis atamisquea Kuntze (Capparidaceae) (according to Morello 1958).

Figures

FIGURE 12. The type locality of Puelchesia gracilis.

FIGURE 13. Distribution of Puelchesia gracilis.

FIGURES 1 – 2. Puelchesia gracilis dorsal and lateral view.

FIGURES 3 – 11. Puelchesia gracilis; 3) head and pronotum, dorsal view; 4) head, ventral view; 5) antenna, dorsal view; 6) left hind wing; 7) left mesotibia and tarsus; 8) left metatibia and tarsus; 9) metatibial apex; 10, 11) male genitalia, lateral and dorsal view.