平形属一新种(吸虫纲:双腔科)

A NEW SPECIES OF PLATYNOTREMA NICOLL, 1914 (TREMATODA: DICROCOELIIDAE)

本文报道寄生在环颈雉Phasianus colchicus decollatus Swinhoe胆道内的双腔科、平形属一新种,定名为肥大平形吸虫Platynotrema fatomagna sp.nov.

A new species of Platynotrema Nicoll, 1914 (Family: Dicrocoeliidae Odhner, 1912) was found in the bile duct of pheasant Phasianus colchicus dccollatus Swinhoe from Sangzhi County, Hunan Province, China in May, 1988.Platynotrema fatomagna sp. nov. (fig. 1)Description (based on 5 specimens) Body unspined, large, elongated elliptically, 9.23-11.20 × 5.56-6.84 mm (10.48 × 648 mm). Oral sucker subterrninal, 0.33-0.52 × 0.46-0.52 mm (0.42 × 0.52 mm). Muscular pharynx small, 0.158-0.190 × 0.210-0.251 mm (0.171 × 0.230 mm). Oesophagus 0.13-0.66 mm (0.40 mm), ceca with wide cavity terminating in 1.66-2.45 mm from posterior extremity. Acetabulum larger than oral sucker, 0.63-0.93 × 0.76-0.93 mm (0.78 × 0.85 mm). Ratio of suckers 1:1.75.Testes two, large, symmetrical in front of acetabulum, deeply branched; branches of left one 6-8, 1.30-3.03 × 1.03-2.92 mm (2.42 × 2.09 mm) and the right one with 7 branches, 1.42-3.35 × 1.42-2.64 mm (2.37×2.08 mm). Cirrus pouch small, situated just behind the intestinal bifurcation, 0.41-0.63 × 0.14-0.24 mm (0.53×0.19 mm). Genital pore situa-ted on the ventral surface of intestinal bifurcation.Ovary with 6 branches, behind acetabulum in a short dtstance to the right side of middle line of body, 1.07-1.63 × 1.26-1.71 mm (1.29 ×1.55 mm). Laurer's canal and seminal receptacle present. Seminal receptacle extremely large, round in form, situated ventrally to the ovary, 0.28-0.70 mm (0.55 mm). Vitellaria follicles forming cluster situated behind testes on each side of hindbody, extending 2.50-3.85 mm (3.36 mm). Numerous uterine coils occupying whole hindbody. Eggs darkbrown in colour, 0.040-0.050 × 0.019-0.025 mm (0.045 × 0.024 mm).The new species differs from all the other species of genus Platynotrema in shape, size of body, deeply branched testes and ovary.. Host Pheasant Phasianus colchicus decollatus Swinhoe.Locality bile duct.Habitat Sangzhi County, Hunan Proving e, China (29°3'N, 110°1'E).Type and paratypes specimens are deposited in Institute of Zoology, Academia Sinica, Beijing, China.