Figs. 10, 13, 27–39

Black. A small spot on lamellate carina of head and on slightly raised caudal margins of scutellum and triangular costal spot on middle of forewing, yellow. Forewing with apex of outer claval vein, clavus and surrounding area, round spot near inner angle of costal triangle yellowish brown. Legs, labium, antennae, abdominal sterna yellow. Genital segments infuscate.

Pronotum with median carina extending entire length.

Male genitalia: Ventro-cephalic lobes of tenth segment about as long as tenth segment. Caudal margin of pygophore rather straight, ventral process straight, without wavy ridge. Stem of connective about twice as long as arms. Aedeagal shaft of uniform width in lateral aspect, slightly produced anteriorly near apex, with paired ventrally directed subapical curved processes.

Female genitalia: Hind margin of female seventh sternum twice as wide as long, with small median lobe.

Measurements: Male 5.1–5.6 mm long, 0.95–1.0 mm wide across eyes, 1.1–1.2 mm wide across hind margin of pronotum. Female 6.3–6.4 mm long, 0.98–1.2 mm wide across eyes and 1.3–1.4 mm wide across hind margin of pronotum.

Material examined: Holotype ♂, INDIA: Karnataka: Jog Falls, 534 m, 17.xi.1976, C.A. Viraktamath (UASB). Paratypes: INDIA: Karnataka: 6 ♀, Jog Falls, 534 m, 17.xi.1976 (1♀), 19.xi.1976, C.A. Viraktamath (3 ♀); 3.xii.1982, H.V.A. Murthy (2 ♀); 19.xi.1983, S. Viraktamath; 1♀, Bhagamandal, 30.i.1983, Shashidhar; 5 ♂, 4 ♀, Kollur, 8.i.1984, S.A. Viraktamath; 1 ♂, Mudigere, 3.vi.1978, A.R.V. Kumar; 2 ♂, 1♀, Dharmasthala, 22.xi.1984, (1♂, 1♀, 17.i.1984, S. A. Viraktamath (1♂); 1♀, 3 Km NE Udupi, Hebri, 11.i.1984, S.A. Viraktamath; 1 ♂, 3 Km W Yellapur, 15.x.1977, 1 ♂, 2♀, Yellapur, 15.xii.1983 (1♂, 1♀), 23.i.1973 (1♀), C.A. Viraktamath; 2 ♀, 25 Km, W Shimoga, 26.xi.1983, H.V.A. Murthy (BMNH, NPC, UASB, USNM, ZSI). Other material: 3 ♀, Kemmannagundi, 9–11.iv.1975, C.A. Viraktamath (UASB).

Remarks: P. biramosus can be readily recognized by the yellow spot on the vertex not extending along the lamellate median carina and from other species of Pythamus from the Indian subcontinent by the apical aedeagal processes.