Philonthus jenseni Bernhauer, 1912

Chani-Posse, Mariana, 2010, Revision of the southern South American species of Philonthus Stephens (Coleoptera: Staphylinidae) 2595, Zootaxa 2595, pp. 1-70 : 34-35

Philonthus jenseni Bernhauer, 1912

( Figs. 81–86, 149)

Philonthus jenseni Bernhauer, 1912: 42 ; Bernhauer and Schubert, 1914: 341 (catalog); Bruch, 1915: 445 (catalog); Blackwelder, 1944: 133 (list); Herman, 2001b: 2849 (catalog); Chani-Posse, 2004: 231 (list).

Diagnosis. Philonthus jenseni may be identified by its body coloration, the antennal segment 8 quadrate and the pronotum distinctly narrowed anteriad. It differs from P. pallipes by the head about as long as wide, the distance separating medial interocular punctures on frons less than twice as large as distance separating medial punctures from lateral punctures, and the eyes as long as temples seen from above.

Redescription. Length of the body 4.5–5.0 mm. Coloration. Head black; thorax castaneous; elytra castaneous to castaneous- piceous at base and lateral margins, brunneous to testaceous medially; abdomen piceous to piceous-brunneous at last abdominal segments; antennae, palpi and legs brunneous to testaceousbrunneous.

Head as long as wide (HW/HL= 1.0) and at basal third as wide as distal third, distinctly to moderately narrower than pronotum (HW/PW= 0.80–0.76); dorsal surface coarsely and moderately punctate, with three postocular punctures and two to three epicranial punctures; distance separating medial interocular punctures on frons less than twice as large as distance separating medial punctures from lateral punctures; infraorbital ridge present, not extending beyond postgenal ridge. Eyes as long as temples (EL/TL= 1.0) seen from above. Antennae with segment 1 distinctly shorter than segments 2 and 3 combined, segments 2 and 3 subequal in length, 4 and 5 elongate, 8–10 quadrate. Labial palpus with last segment about 1.4–1.8 times as long as preceding segment. Maxillary palpus with last segment about 1.5 times longer than segment 3. Submentum 1.5 times as long as mentum. Neck no more than 0.6 times as wide as head at widest point (NW/HW= 0.5).

Pronotum about as long as wide (PW/PL= 1.0–0.97), distinctly narrowed anteriad; dorsal surface of pronotum with two rows of punctures, each with six punctures. Hypomeron not visible in lateral view. Basisternum with medial longitudinal carina moderately developed, bulbous. Metasternum with circummesocoxal ridge broadly rounded medially. Elytra at sides distinctly longer than pronotum at midline (EtL/ PL=1.6–1.5), about 1.5 times as long as elytra along suture (EtL/Etl= 1.7), and longer than wide at base of elytra (EtL/EtW=1.2–1.1); transverse distance between punctures about as large as diameters of punctures. Front tarsi as long as front tibiae; middle tarsi shorter than middle tibiae; first segment of hind tarsus as long as segments 2 and 3 combined, and as long as last segment (S1/S5= 1.0). Abdominal terga coarsely punctuate at basal area, distance separating punctures distinctly smaller than diameters of punctures; terga 2 and 3 with elevated area between basal lines punctuate, posterior basal line straight medially. Male sternum 7 with apical margin slightly notched at middle. Tergum 8 in both sexes with posterior margin truncate.

Male genitalia. Sternum 8 moderately emarginate medio-apically. Tergum 10 wide and subangulate medio-apically ( Fig. 82), with two long subapical macrosetae and 8–10 apical setae. Sternum 9 acutely emarginate apically with two long subapical macrosetae and one apical setae at each side ( Fig. 81). Aedeagus with median lobe gradually narrowed from apical third of paramere; apex of median lobe subrectangular (in dorsal view); paramere reduced and fused to median lobe ( Figs. 83–84). Internal sac with distinctly sclerotized structures ( Fig. 83).

Female genitalia. Tergum 10 arcuate medio-apically, with two long subapical macrosetae and 8–10 apical setae ( Fig. 86). Second gonocoxite with 2–5 strong setae along its outer margin, and stylus with two apical setae ( Fig. 85).

Bionomics. Unknown.

Geographical distribution. P. jenseni is only known from the biogeographical provinces of Monte and Chaco in northwestern and central Argentina ( Fig. 149).

Type material. Lectotype (here designated; Figs.), ♀, with labels: “Channar Reg. lg. Jensen” “ jenseni Brnh / Typus” “Chicago NHMus. /M. Bernhauer Collection” “ Lectotype Philonthus jenseni Bernhauer, 1912 / Des. Chani-Posse de Maus 2008 ” ( FMNH). Paralectotypes: 2 ♂, 2 ♀ with labels: “Channar Reg. lg. Jensen” “ jenseni Brnh / Cotypus” “Chicago NHMus. /M. Bernhauer Collection” “ Paralectotype Philonthus jenseni Bernhauer, 1912 / Des. Chani-Posse de Maus 2008 ” ( FMNH).

Additional material: 11 specimens (2 ♂, 2 ♀, 7 unsexed)

ARGENTINA: Catamarca: La Viña , XI/21/1995, L. Herman, 610m, 28° 03' S, 65°35'W, Leaf litter near stream, 2893-2896, 1 specimen ( AMNH) . Mendoza: Malargue, Pto. La Aguadita , PP Payunia, 6/1/03, S. Roig, 1 ♂ ( IADIZA) ; C. Bruch, 190, in green "cotypus", Channar g. Jensen, Philonthus jenseni cotipo Bernh, in Bernhauer handwriting " jenseni Brh. ", 1 specimen ( MACN) . San Luis: 45 km S San Francisco del Monte de Oro , XII-3-2000, L. Herman, 900m, 32° 346' 53''S, 66° 16' 43''W, 1 ♂, 2 ♀, 2 specimens ( AMNH) ; Quebrada López , 7 km S San Francisco del Monte de Oro, L. Herman, 32° 39' 37''S, 66° 07' 46''W, 1 specimen ( AMNH) ; Renca, Rio Conlara , XII-8-2000, L. Herman, 760m, 32° 46' 21''S, 65° 22' 04''W, litter near river, 1 specimen ( AMNH) . Tucumán: reservoir just S. Tafí del valle, Jan. 3, 1982, RT Schuh and B. M. Massie, 1900m, sandy-muddy margin scattered vegetation, 1 specimen ( AMNH) .