Philonthus varians ( Paykull, 1789 )

Chani-Posse, Mariana, 2010, Revision of the southern South American species of Philonthus Stephens (Coleoptera: Staphylinidae) 2595, Zootaxa 2595, pp. 1-70 : 62

Philonthus varians ( Paykull, 1789)

( Figs. 139 –144, 149)

Staphylinus varians Paykull, 1789: 45 . For complete references see Herman (2001b).

Diagnosis. Philonthus varians may be identified, and distinguished from P. argus and P. stenocephalus , by the character states given below.

Redescription. Length of the body 6.8–7.5 mm. In most character states similar to P. argus and P. stenocephalus , but different as follows: body color castaneous-piceous to piceous-black, basomedial area of reddish to reddish-brunneous. Head similar to that of P. stenocephalus , but submentum 1.5 times as long as mentum. Pronotum about as long as wide (PW/PL=1.0), and dorsal rows of punstures each with five punctures. Tergum 8 truncate apically in both sexes.

Male genitalia. Sternum 8 similar to P. argus , deeply emarginate apically.Tergum 10 subacute apically ( Fig. 139), with two long subapical macrosetae and two apical setae. Sternum 9 similar to P. stenocephalus , deeply emarginate apically, with two long subapical macrosetae, and two apical setae at each side ( Fig. 140). Aedeagus with median lobe narrowed from base of paramere, apex of median lobe subtruncate apically (in dorsal view) and simple in its apical fourth (in lateral view); paramere elongate and entire, leaf-like, reaching four fifths of median lobe length, with two lateral rows of sensory peg setae joined at apex ( Figs. 141–143). Internal sac with no distinctly sclerotized structures.

Female genitalia. Tergum 10 subacute medio-apically, with four long subapical setae and without apical setae. Second gonocoxite with 2–5 strong setae along its outer margin, and stylus with two long apical setae (Fig. 144).

Geographical distribution. Philonthus varians is a Palaearctic species which was probably introduced in the New World during the second half of the 19 th century ( Smetana 1995; Herman 2001b). It was first recorded in southern South America by Scheerpeltz (1972). After examining material of southern South American species of Philonthus from different collections, I have only found specimens of P. varians from Chile ( Fig. 149).

Bionomics. Philonthus varians is found in decaying organic materials, such as carrion, dung, weeds, rotting tissues, compost piles, etc. Specimens have been collected in flight intercept traps, carrion and dung baits. Trapping data suggest that this species is attracted both to carrion and dung. Frank (1982) also cites this species as parasitized by Laboulbeniales (Fungi, Ascomycetes).

Type material. Paykull (1789: 45) described the species from specimens from Sweden. I was not able to see the original material but there is little doubt that this species, as interpreted by modern authors (e.g. Lohse 1964; Smetana 1995) is the species that Paykull described.

Additional material: 21 specimens (11 ♂, 8 ♀, 2 unsexed)

CHILE: Cautín: Bellavista, North Shore Lago Villarica , 15–29.XII.1985, A. Newton & M. Thayer, 310m, carrion trap (squid), 1 ♂ ( FMNH); P.N. Conguillio, 1.5km Laguna Captren, 23.XII.1996 – 5.II.1997, A. Newton & M. Thayer, 1365m, flight intercept trap, Philonthus varians Payk Det. M. K. Thayer 2004 , 1 ♂ ( FMNH); Volcan Villarica, road to ski center, 23.XII.1996 – 5.II.1997, A. Newton & M. Thayer, 1180m, carrion trap (squid), 2 ♂, 3 ♀ ( FMNH) . Chillán: P. Comadres, 12.1.1995, S. Roitman, 1 specimen ( MNHN) . Chiloe: Castro, S. of Cabañas Trayen, XII.2002, Solodovnikov, Newton, Chani, Thayer, 38° 67' S, 71° 41.37' W, 2 ♂, 2 ♀ ( FMNH). Coihaique : 20km ENE of Coihaique, Dos Lagunas, 600m, carrion trap beech groves in steppe, Philonthus varians Pk Det. Chani-Posse 2006 , 1 ♂ ( FMNH) . Curicó: Hueca-Huecan, camino Zapallar , 10km E. Curicó, 22–31 dic 1997, 1 ♀ (Col. J. E. Barriga) . La Araucania: Nahuelbuta, Pehuenco near campground, 15–16.ii.2004, A. Smith, M. Paulsen, J. Mondaca, 1120m, 1 ♀ ( FMNH) . Llanquihue: P.N. Vicente Perez Rosales, 9.2km NE Ensenada on road to Petrohue , 2–28.i.1997, A. Newton & M. Thayer, 125m, 41° 10.20' S, 72° 27.10' W, carrion trap (squid), 1 ♀ ( FMNH) . Osorno: Parque Nac. Puyehue, 18– 25.XII.1986, A. Newton & M. Thayer, 965m, carrion trap (squid), 2 ♂ ( FMNH); vic. Aguas Calientes sendero Bertin , 18.XII.2002, Solodovnikov, 965m, 40° 45' S, 72° 18' W, 1 ♂ ( FMNH) . Santiago: Pudahuel , 29.X.1953, L. E. Peña leg., 1 ♂ ( FMNH); 1 specimen ( MNHN) .