Plochionocerus modestus Asiain, Márquez & Morrone, 2007

Asiain, Julieta, Márquez, Juan & Morrone, Juan J., 2007, Phylogenetic systematics of the genera Plochionocerus Dejean and Agrodes Nordmann (Coleoptera: Staphylinidae: Xantholinini), Zootaxa 1584, pp. 1-53 : 24

Plochionocerus modestus Asiain, Márquez & Morrone , sp. nov.

Type material. Holotype, male: “ VENEZUELA, Caracas / Venezuela. 55.59 / Holotype Plochionocerus modestus Asiain, Márquez & Morrone, 2007 ” ( BMNH).

Description. Total length 18.0 mm. Metallic violet.

Head. Subquadrate, slightly oblong (length/width: 1.24), moderately wider than pronotum (1.1 times); dorsally slightly convex, ventrally flat and with moderately dense, expanded, umbilicate punctures (10–19 in each half of head; similar to Fig. 50 ); first antennomere 1.68 times as long as antennomeres 2+3 combined, second antennomere 0.75 times as long as third antennomere, antennomere 4 subquadrate, antennomeres 5–10 transverse, antennomere 9 as long as antennomere 10, apical antennomere in male moderately oblong (length/ width: 1.42), as long as antennomeres 9+10 combined; mandibles without basal external channel.

Thorax. Pronotum moderately oblong (length/width: 1.34); shorter than elytra (0.83 times their length); with two clearly visible depressed areas in posterior third ( Fig. 56 ). Prosternum transverse (length/width: 0.72).

Aedeagus. Ovate, length 2.8 mm, with parameres moderately long (0.41 times as long as median lobe), apical area of median lobe 0.33 times as long as the total length of median lobe, and internal sac moderately visible ( Fig. 86 ).

Comparative notes. The head of the only specimen is subquadrate, but the posterior angles are somewhat convex, so it is difficult to be precise about its shape. Because the head is subquadrate, and the dorsal and ventral surfaces are flat or moderately convex, and the apical antennomere in male is as long as antennomeres 9+10 combined, this species can be confused with P. h u m e r a l i s, P. fulgens and P. simplicicollis . From P. humeralis it is distinguished by antennomere 9 being as long as antennomere 10 in the male, the slightly dense, ventral punctation of the head and the ovate aedeagus. From P. fulgens it is separated by the moderately oblong head, the small, ovate aedeagus and with the moderately visible internal sac; and from P. simplicicollis by the slightly dense, umbilicate punctures on the ventral surface of the head and the absence of the external basal mandibular channel.

Geographical distribution. Venezuela.

Etymology. The name of this species refers to the moderate range of its characters, when compared with other species of the genus.

Figures

FIGURES 48 – 53. Cephalic ventral view: 48, Renda flagellicornis; 49, Philonthus testaceipennis; 50, Plochionocerus simplicicollis; 51, P. gracilis; 52, P. h e r m a n i; 53, P. puncticeps.

FIGURES 54 – 62. Pronotum: 54, Philonthus testaceipennis; 55, Renda flagellicornis; 56, Plochionocerus simplicicollis; 57, P. reticularis. Elytra: 58, Agrodes spp.; 59, Plochionocerus spp. Midleg: 60, Philonthus testaceipennis; 61, Agrodes spp.; 62, Plochionocerus spp.

FIGURES 79 – 87. Ventral (left) and lateral (right) view of aedeagus: 79, Plochionocerus fulgens; 80, P. h e r m a n i; 81, P. humeralis; 82, P. ig neu s; 83, P. impressipennis; 84, P. janthinus; 85, P. marquezi; 86, P. modestus; 87, P. newtonorum. Scale bar 1 mm.