Philonthus ruficauda Bernhauer, 1934

Chani-Posse, Mariana, 2010, Revision of the southern South American species of Philonthus Stephens (Coleoptera: Staphylinidae) 2595, Zootaxa 2595, pp. 1-70 : 50-51

Philonthus ruficauda Bernhauer, 1934

(Figs. 6, 8, 14, 121–127, 149)

Philonthus ruficauda Bernhauer, 1934: 119 ; Blackwelder, 1944: 134 (list); Herman, 2001b: 2945 (catalog); Chani-Posse, 2004: 231 (list).

Diagnosis. Philonthus ruficauda may be identified by its body coloration and the head wider than long. It differs from other southern South American species of Philonthus by the eyes shorter than temples, the dorsal rows on pronotum each with four punctures and the shape of aedeagus.

Redescription. Length of the body 5.7–6.5 mm. Coloration. Head piceous- black; thorax castaneousbrunneous; elytra castaneous-piceous; first abdominal segments castaneous-piceous with apical margins paler, seventh and eight visible segments castaneous-brunneous to testaceous-brunneous; antennae castaneouspiceous, palpi and legs castaneous-brunneous.

Head moderately to distinctly wider than long (HW/HL= 1.3–1.1) (Fig. 6) and at basal third as wide as distal third in both sexes, moderately narrower than pronotum (HW/PW= 0.90–0.82); dorsal surface coarsely and moderately punctate, with three to four postocular punctures and three to four epicranial punctures; distance separating medial interocular punctures on frons about twice as large as distance separating medial punctures from lateral punctures; infraorbital ridge present, extending not far beyond postgenal ridge. Eyes distinctly shorter than temples (EL/TL= 0.75–0.67) (Fig. 6) seen from above. Antennae with segment 1 as long as segments 2 and 3 combined, segments 2 and 3 subequal in length, segments 4–6 elongate, 7–8 quadrate, 9–10 transverse. Maxillary palpus with segment 2 not swollen, more than twice as long as its maximum width; last segment fusiform, about twice longer than segment 3 (Fig. 6). Submentum about twice as long as mentum (Fig. 8). Labial palpus with last segment about 1.5 times as long as preceding segment (Fig. 8). Neck about 0.5 times as wide as head at widest point (NW/HW= 0.6–0.5).

Pronotum about as wide as long to slightly wider (PW/PL= 1.08–1.02), distinctly narrowed anteriad; dorsal surface of pronotum with two rows of punctures, each with four punctures. Hypomeron not visible in lateral view. Basisternum with medial longitudinal carina moderately developed, bulbous. Metasternum with circum-mesocoxal ridge broadly rounded medially. Elytra at sides moderately to distinctly longer than pronotum at midline (EtL/PL=1.4–1.2), distinctly longer than elytra along suture (EtL/Etl= 1.8–1.6); transverse distance between punctures about as large as to distinctly smaller than diameters of punctures. Both front and middle tarsi as long as front and middle tibiae; first segment of hind tarsus moderately longer than segments 2 and 3 combined, and longer than last segment (S1/S5= 1.5–1.4). Abdominal terga distinctly punctuate at basal area, distance separating punctures more than diameters of punctures; terga 2 and 3 with elevated area between basal lines impunctuate, posterior basal line straight medially ( Fig. 14). Male sternum 7 with apical margin straight. Tergum 8 in both sexes with posterior margin arcuate.

Male genitalia. Sternum 8 deeply emarginate medio-apically. Tergum 10 wide and subangulate to subtruncate medio-apically ( Fig. 123), with two long subapical macrosetae and two apical setae. Sternum 9 with moderate triangular emargination apically, two long subapical macrosetae and two long apical setae at each side ( Fig. 122). Aedeagus with median lobe gradually narrowed from apical third; apex of median lobe acute (in dorsal view) and curved downwards at an angle in its apical fourth (in lateral view); paramere elongate and entire, leaf-like, with apex acute, reaching two thirds of median lobe length, with two lateral rows of sensory peg setae joined at apex ( Figs. 124, 125). Internal sac with distinctly sclerotized structures ( Figs. 124, 125).

Female genitalia. Tergum 10 similar to that of male with four apical setae ( Fig. 126). Second gonocoxite with one strong seta basally and stylus with two long apical setae ( Fig. 127).

Geographical distribution. P. ruficauda is at present only known from Argentina, where it was recorded from the Chaco, Yungas and Parananense biogeographical provinces of the Neotropical region ( Fig. 149).

Bionomics. Philonthus ruficauda has been collected from leaf litter near decaying tree trunks in cloudy forests. No further data available.

Type material. Holotype, ♀, with labels: “Rep. Argentina / Tucuman / 190 C. Bruch”, “ ruficauda Bernh. Typus unic, don. Bruch” (yellow label), “Chicago NHMus. /M. Bernhauer Collection” “ Holotype Philonthus ruficauda Bernhauer, 1934 / Des. Chani-Posse de Maus 2008 ” ( FMNH).

Notes. In the original description Benhauer (1934) stated that he had a unique specimen of P. ruficauda . The specimen mentioned above agrees with the original description by Bernhauer (1934), being the holotype fixed by monotypy ( ICZN 1999, Article 73.1.2).

Additional material: 38 specimens (5 ♂, 6 ♀, 27 unsexed)

ARGENTINA: Chaco: II. 1936, M. J. Viana, in yellow in Bernhauer handwriting " ruficauda Bernh. det. Bernhauer, don. M. J. Viana ", Chicago NHMus Bernhauer Collection/ Philonthus ruficauda Brnh. , "Metatipo", 1 specimen ( FMNH), 2 specimens ( MLPA) . Jujuy: Termas de Reyes , December 27, 1971, Lee Herman, 5 ♂, 6 ♀, 6 specimens ( AMNH) ; Calilegua Nt. Pk. , 20-X-1994, J. Carpenter, D. Agosti, 850m, 23° 44' 34''S, 64° 51' 13''W, transition forest & lianas, partial decid. Leaflitter nr. decaying tree trunk, 3 specimens ( AMNH) ; Philonthus rufiventris Bernh. , 1 undetemined ( MACN), 1 specimen ( MLPA) . Misiones: Loreto, Dr. A. Ogloblin, Philonthus longicornis Steph. , 1 specimen ( MACN), 2 specimens ( MLPA) . Tucumán: Rio de las Tacanas , VII. 1933, in green card "Cotype"/in green card " Cotype ", Philonthus bosqianus Bnrh. , 4 specimens ( MLPA) ; Siambon , VII. 1933, in green card "Cotype", 1 specimen ( MLPA) ; 6km, N San Javier XI/ 19/1995, L. Herman, 1200m, 26° 43' S, 65° 23' W, 2887, 4 specimens ( AMNH) ; 22km, SW Tucumán, Quebrada Lules , Dec. 23, 1971, L. Herman, 1 specimen ( AMNH) .