5 NEW SPECIES OF TRICHOSTOMATIDA (CILIATED PROTOZOA) FROM THE COLON OF WILD AFRICAN RHINOCEROSES

Five new species of Charonina Strand, 1928 were revealed, in addition to 41 species of 20 other apparent genera, in a survey of ciliated int estinal protozoan endocommensals of both black and white wild African rhinoceroses. Charonina species infected the ventral and dorsal region of the ascending colon, where the average total protozoan populations (x 10(3)/ml digesta fluid) were 100 and 80, respectively, in the whit e and 270 and 260, respectively, in the black rhinoceroses. Charonina species constituted up to 50% in the ventral and 25% in the dorsal pop ulations. Measurements in micrometres and specific characteristics of the five species are: C. odontophora n. sp. length 70 +/- 5.7, width 3 2 +/- 7.2, dorso-ventral thickness 7 +/- 1.1, slender ovate-lanceolate -shaped body with frontal lobe and prong-like protrusion in oral-openi ng; C. tortuosa n. sp. length 87 +/- 9.3, width 42 +/- 5.3, dorso-vent ral thickness 15 +/- 2.7, body-shape ovate-lanceolate without frontal lobe, oral-opening with longitudinal ridge, cytopharyngeal canal with sharp bend after emerging from oral-opening; C. dicerotis n. sp. lengt h 67 +/- 8.6, width 37 +/- 4.0, dorso-ventral thickness 12 +/- 2.2, bo dy-shape ovate-lanceolate without frontal lobe, oral-opening without r idge, cytopharyngeal canal curved without sharp bend; C. tenuis n. sp. length 56 +/- 10.0, width 16 +/- 4.1 at anterior end and 10 +/- 2.7 a t posterior end, dorso-ventral thickness 7 +/- 1.2 at anterior end and 5 +/- 1.1 at posterior end, body-shape cone-like with longitudinal st riations and frontal lobe; C. tetragona n. sp. length 58 +/- 4.7, widt h 26 +/- 3.2, dorso-ventral thickness 12 +/- 1.8, body-shape rectangul ar with frontal lobe and caudal flaps. The length, width and dorso-ven tral thickness of the five species are on average in the approximate r atio of 6:3:1, thus showing them to be dorso-ventrally compressed. The body conformation of C. tetragona n. sp. closely resembles that of Di desmis quadrata Fiorentini, 1980, but is distinguished from the latter by the absence of a concrement vacuole and the presence of an elongat e cytopharyngeal canal.