Light and scanning electron microscopic description of rhadinorhynchus bicircumspinis hooper 1983 (acanthocephala)‎ infecting the bayad bagrus bajad (bagridae)‎ : new host and locality records from the River Nile, Qena, Egypt

الملخص EN

Rhadinorhynchus bicircumspinis, an acanthocephalan parasite recovered from the intestine of Bagrus bajad (Bagridae) captured from water locations along the River Nile at Qena governorate.

Ten/seventy (14.28%) were infected.

Morphologically and morphometrically by light and scanning electron microscopy, parasite was creamy white, slightly curved without annulations.

Body was 7-10 (8±2) mm long x 0.52- 0.71 (0.62±0.02) mm wide in male & 7-15 (12±2) mm long and 0.43-0.68 (0.55±0.02) mm wide in female.

Proboscis, long, with short neck measured 1.42-1.83 (1.66±0.02) mm in males &1.54-1.96 (1.75±0.03) mm in females, covered with 12-15 rows of 20-23 hooks each.

Proboscis receptacle elongated and double walled lemnisci were two, tubular, elongated on proboscis receptacle sides.

Trunk was long, spinose anteriorly.

Two postequatorial contiguous testes were observed in male worms with four very long tubular cement glands overlapped at the posterior margin of posterior testis.

In female worms, ovarian balls, uterus and a short vagina were observed at the posterior end of the body cavity.

Immature, fusiform eggs with polar prolongations were recorded in the body cavity.

No mature eggs seen.

Genital pore was subterminal.

The present parasite was compared with similar species from different hosts, R.

selkirki, R.

trachuri, R.

cololabis and R.

pristis, which showed that the isolated parasite was R.

bicircumspinis as a new host and locality; the River Nile at Qena Governorate in Egypt