Pericompsus (Pericompsus) catamarcensis, Roig-Junent & Scheibler, 2004

Roig-Juñent, Sergio & Scheibler, Erica, 2004, A New Species Of Pericompsus LeConte (Carabidae: Bembidiini, Tachyina) From Argentina, The Coleopterists Bulletin 58 (3), pp. 311-315 : 312-315

Pericompsus (Pericompsus) catamarcensis , new species

Type Material. HOLOTYPE male labelled: Catamarca, 28 Km SE Tinogasta, 20- X-1997, 28°14.89 S, 67°27.49 W, col. S. Roig ( IADIZA) . PARATYPES. 16 specimens labelled: Catamarca, 28 Km SE Tinogasta, 20-X-1997, 28°14.89 S, 67°27.49 W, col. S. Roig ( IADIZA; AMNH, ILMA, MLPA, UASM) ; 1 specimen labelled: Catamarca, San Fernando , 17-X-97, 27°20.41 S, 66°54.46 W, col. S. Roig ( IADIZA) ; 2 specimens labelled: Catamarca, 5 Km N de Belén, 19-X-97, 27°37.19 S, 67°1.01 W, col. S. Roig ( IADIZA) .

Specific Epithet. The word catamarcensis is the latinized adjectival from Catamarca, the Argentinean province where the new species has been found.

Diagnosis. Three supraorbital setae; pronotum with six setae; interneur 8 with two foveae, one small at the basal third and deeper one at the middle; antennomeres 1–3 yellow or reddish, 7–11 black.

Description. Length 2.6–2.8 mm. Habitus as in Figure 1 : short, forebody narrow, narrower than elytra, subpedunculate; elytra slightly inflated, with broad marginal explanations, convex.

Color. —Head, pronotum and elytral color base orange-reddish; elytra with a red brownish subhumeral maculae; central region also red brownish, with a yellow macula extended from the 7 interneur to the interneur 2; apex of elytra orange-reddish. Venter of head and prothorax yellowreddish; meso and metathorax venter orange-reddish. Pro and mesocoxa yellow-orange, metacoxa reddish; legs yellow. Labial and maxillary palpomeres yellow.

Head. —Across eyes slightly narrower than width of pronotum; three supraorbital setae per eye; frontal furrows well impressed and arcuate, posteriorly extending to the posterior margin of eye; eyes large and prominent.

Prothorax. —Pronotum chordate, sides sinuate and strongly sinuate in basal half; base broadly lobed; hind angles rounded; sides margins not reflexed, each with six (seven in one specimen) setigerous punctures, five in the anterior half, and one in the hind angle; disk convex.

Elytra. —Each elytron with 6 punctate interneurs; punctures weak; all rows effaced at apical third; intervals plurisetose; interneur 7 effaced externally throughout; interneur 8 well impressed with two fovea, one small on the basal third, and second at middle; deep, rounded and half as large in diameter as width of the elytral explanation; humeral margin strongly rounded curved at base, but not connected to base of interneur 4; sides margins setose from base to apex; setae 1.5 or more as long as width of elytral explanation, side margin not serrate; chaetotaxy Eo-1a, 2a, 3a, 4c, 5c, 6a, 7, 8a, and Ed-1, disc plurisetose, 7c, 8; plica short and well developed externally. Microsculpture mostly effaced except at extreme elytral apex, where it shows an isodiametric reticulation.

Male Genitalia ( Fig. 2 ).—Similar to P. hirsutus Schaum , but with the apex of median lobe more elongate and acute.

Variation. The dorsal body color is variable. Some specimens are almost dark red brown, except the antennomeres 1–3, the apical macula of elytra, and legs that are paler. Other specimens are almost pale yellow, except the antennomeres 7–11 and the subhumeral and central maculae of elytra.

Distribution. The specimens are from three different localities of the Catamarca Province in Argentina ( Fig. 3 ), between parallels 27° and 28° South. The combined range known for the other species of the hirsutus group was between parallels 3° and 23° South (Erwin 1974). The discovery of Pericompsus catamarcencis extends this range about 500 km South to 28°S latitude.

Habitat. All specimens of Pericompsus catamarcensis were found under rocks, on the borders of creeks and rivers. The vegetation that surrounded those margins is a shrubby steppe of Larrea Cavanilles (Creosote bush), corresponding to the habitat of the northern part of Monte Biogeographical province (Roig-Juñent et al. 2001). In this dry area, the Monte desert, bembidines are found near rivers or small creeks.

Relationship to Other Species of Pericompsus . The presence of a deep fovea on the interneur 8 in the middle of elytron places this new species within the subgenus Pericompsus . Within this subgenus it is placed in the hirsutus group due to the presence of numerous long setae arranged in rows along the intervals, and also by the presence of accessory setae along elytral and pronotal margins. Pericompus catamarcensis also has three supraorbital setae per eye, a character shared exclusively within the genus with two species of the hirsutus group: Pericompsus polychaetus Erwin and Pericompsus grosseopunctatus Bates.

The key of Erwin (1974) must be modified to include Pericompsus catamarcensis as follows:

26(25) Head each side with two supraorbital setiferous punctures; pronotum with well-defined lateral bead, with three setae - - - - - - - - - - - - - - - - - - - P. hirsutus Schaum.

– Head each side with three supraorbital stiferous punctures; pronotum with well-defined lateral bead in basal two-thirds, with four or more setae - - - - - 27

27(26) Antennal articles uniformly testaceous; pronotum with four setae - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - P. grosseopunctatus Bates

– Antennal articles 1–3 testaceous, 4–11 different to basal; pronotum with five to seven setae - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 27 9

27 9 (27) Antennal articles 4–6 infuscated, 7–11 light-yellow; pronotum with five setae; interneur 8 with one large fovea at middle, twice as large in diameter as width of the elytral explanation - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - P. polychaetus Erwin

– Antennal articles 4–11 black; pronotum with six (in some cases seven) setae; interneur 8 well impressed with two fovea, one small on the basal third, and second at middle; deep, rounded and half as large in diameter as width of the elytral explanation P. catamarcencis new species

Figures

Fig. 1. Habitus of Pericompsus catamarcencis new species. Scale bar ¼ 1 mm.

Fig. 2. Aedeagus of Pericompsus catamarcencis, lateral view. Scale bar ¼ 0.25 mm.

Fig. 3. Geographical distribution of Pericompsus catamarcencis.