Philonthus trilobatus Tottenham, 1949

Hromádka, Lubomír, 2010, A revision of the Afrotropical species of the Philonthus arrowianus species group (Coleoptera: Staphylinidae: Philonthina), Acta Entomologica Musei Nationalis Pragae 50 (1), pp. 131-144 : 140-143

Philonthus trilobatus Tottenham, 1949

( Figs. 30–32 )

Philonthus trilobatus Tottenham, 1949: 335 .

Type locality. Democratic Republic of the Congo, Lubero. Type material examined. HOLOTYPE: J, ‛ Democratic Republic of the Congo, Lubero , 24.-28.viii.1932, L. Burgeon, Musée du Congo, // Philonthus trilobatus Tottenham , TYPE [yellow square label, handwritten]’ ( BMNH).

Redescription. Body length 12.1 mm, length of fore body (to end of elytra) 5.2 mm.

Colouration. Entirely black, abdomen with slightly bluish iridescence, base of antennomere 2 red.

Head almost quadrate, wider than long (ratio 32.5: 30), sides behind eyes parallel-sided, posterior angles obtusely rounded, each bearing one long black bristle. Distance between medial and lateral punctures four times distance between medial and lateral puncture. Medial punctures slightly shifted anteriad. Eyes vaguely shorter than temples (ratio 11.0: 13.0). Posterior margin of each eye with three coarse punctures. Temporal area with several coarse punctures. Surface without microsculpture.

Antennae slender and long, all antennomeres longer than wide, reaching posterior margin of pronotum when reclined. Relative lengths of antennomeres: 1 = 9; 2–3 = 7; 4–7 = 5; 8–9 = 4.5; 10 = 4; 11 = 7.

Pronotum slightly wider than long (ratio 48: 45), parallel-sided. Anterior angle conspicuously deflexed, vaguely obtusely rounded, with several variably long bristles; posterior angles markedly rounded. Sides bearing bristles of variable length. Each dorsal row with five coarse punctures, punctures 1-4 equidistant, distance between punctures 4-5 slightly larger; each sublateral row with two coarse punctures, puncture 2 slightly shifted laterad. Surface without microsculpture.

Scutellum moderately densely punctate except at base and margins, setation dark.

Elytra combined wider than long (ratio 48: 45), indistinctly widened posteriad, moderately strongly and sparsely punctated, punctures distinctly larger than eye facets, separated by 1.5–2 puncture diameters in transverse direction. Surface without microsculpture; setation dark.

Legs. Metatibia slightly longer than metatarsus (ratio 30: 29), relative lengths of metatarsomeres: 1 = 9; 2 = 5; 3 = 4; 4 = 3.5; 5 = 8.

Abdomen wide, indistinctly narrowed posteriad. First three visible tergites with two basal lines, elevated area between lines with scattered punctures. Punctation at base of all tergites finer and denser than that on elytra, becoming sparser and finer towards posterior margin of each tergite. Surface without microsculpture; setation similar to that on elytra.

Male. Protarsomeres 1–3 strongly dilated and sub-bilobed, each covered with modified pale setae ventrally, protarsomere 4 distinctly narrower than preceding ones. Aedeagus ( Figs. 30–32 ).

Female. Unknown.

Fig. 33. Distribution of the species of the Philonthus arrowianus species group. ● – P. arrowianus Bernhauer, 1931 ; ♣ – P. chappuisi Bernhauer, 1939 ; ♥ – P. currax sp. nov.; ▼ – P. galago sp. nov.; * – P. meges Tottenham, 1949 ; ◊ – P. trilobatus Tottenham, 1949 .

Differential diagnosis. Philonthus trilobatus may be distinguished from the similar P. chappuisi by a narrower head, darker legs and different shape of the aedeagus. Distribution. Democratic Republic of the Congo, known only from the type locality.

Figures

Figs. 30–32. Philonthus trilobatus Tottenham, 1949 (30 – aedeagus, ventral view; 31 – aedeagus, lateral view; 32 – apex of paramere with sensory peg setae).