Timoshkin 1997 (citation)- p. 170-171 Key to the species of Porfirievia genus 1(6) Walls of pharynx tube more or less parallel to each other in sagittal section 2(5) Pharynx cylindrical, distal end more or less straight (not inverted) (Figs. 15.4, 15.5); worms with even lateral body margins 3(4) Pharynx length 150-190 ?m, major and minor cross-sectional diameters about 235 ?m and 150-215 ?m respectively, number of external longitudinal muscles (mel) in wall of pharynx tube 120-156; double layer of external circular muscles (mec) with small enlargement at the distal pharynx end (sphincter) (Fig. 7) and average development of internal longitudinal muscles (mil); worms with intense orange-red colour. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. ermakovi sp.n. 4(5) Pharynx length about 80 ?m, maximum and minimum cross-sectional diameters about 135 and 90 ?m respectively, number of “mel” in wall of pharynx tube 38-46; with homogeneously developed, double layer of “mec” fibres (Fig. 2) and strongly developed “mil” fibres (Fig. 2.2); worms white or light grey. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. minima TIMOSHKIN et ZABROVSKAYA, 1985 5(2) Pharynx cylindrical with thin distal end, often inverted into pharynx tube (Fig. 15.6). Maximum pharynx length 100 ?m, maximum and minimum cross-sectional diameters about 90 ?m and 80 ?m respectively, number of “mel” in wall of pharynx tube 34-35; with homogeneously developed, single layer of “mec” and “mil” fibres (Fig. 12.2, 12.3); worms light-yellow and with sinuous lateral margins of body (Fig. 12.1a) . . . . . . . . . . . . . . . . . . . . . . . P. bathyalis sp. n. 6(1) Walls of pharynx tube in sagittal section situated at an angle to each other 7(8) Pharynx cone-shaped (Fig. 15.3) with thin, pointed distal end; pharynx length 68-110 ?m, maximum and minimum cross-sectional diameters about 145 ?m and 80 ?m respectively, number of “mel” in wall of pharynx tube 31-45; with single, homogeneously developed layer of “mec” fibres; worms lemon-yellow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. xantha sp. n. 8(9) Pharynx hemispherical with short, broad, funnel-shaped lumen (Fig. 15.1); pharynx very short (60-80 ?m), but at same time very broad: maximum and minimum cross-sectional diameters about 150-235 ?m and 140-165 ?m respectively, number of “mel” in wall of pharynx tube 45-73; with two-rowed, homogeneously developed layer of “mec” fibres; epithelium of pharynx wall with numerous papillae; worms light-yellow; body length when fixed 630-1100 ?m. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. barguzinensis sp. n. 9(10) Pharynx hemispherical with long, narrow funnel-shaped lumen (Fig. 15.2); pharynx length 95-120 ?m, major and minor cross-sectional diameters 130-165 ?m and 100-145 ?m respectively; number of “mel” in wall of pharynx tube 30-56; with homogeneosly developed, single layer of “mec” fibres; epithelium of pharynx wall usually without papillae; worms light-grey; body length, when fixed, 960-1700 ?m. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. schirobokovi sp. n. 10(6) Pharynx hemispherical, with long, narrow, funnel-shaped lumen (Fig. 15.2); pharynx length 84-95 ?m; minimum pharynx diameter 110-130 ?m; with one row of “mec” fibres, these being most strongly developed in basal half of pharynx; numerous papillae of pharynx wall epithelium present in basal half of the pharynx only; worms white; body length of fixed specimens 900-1110 ?m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. kawanabei sp. n
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