Genus Cylicodontophorus Ihle, 1922

Synonyms: Cylicostomum (Cylicodontophorus) Ihle, 1922

General. Small to medium-sized Cyathostominea. MC inflated, high, ring-shape, divided into inner and outer rings. Posterior edge of MC posterior or anterior to edge of BC. Amphids not markedly projected through MC surface. Tip and longer stalk of submedian papillae extend through MC. Tip of submedian papillae bullet-shaped. Stalk of submedian papillae broader than long. Elements of ELC more numerous than ILC and longer or equal to them. Elements of ELC longer than broad, tips pointed; insertion point on tips of ILC. Elements of ILC longer than broad, tips pointed or rounded; insertion point at 1/4 or less of BC depth. Line formed by insertion of elements of ILC straight. Form of posterior edge of elements of ILC straight, unadorned. Support for ELC continuous with BC, elongate, curving, thin at one end or short, triangular in optical section. Septum intracoronare origin on support. Medial insertion of septum intracoronare situated anteriorly to junction of ELC and ILC. Walls of BC straight, uniform thickness. Buccal cavity wider than deep, but wider anteriorly or posteriorly. Dorsal gutter slightly more than 1/2 of BC depth. Buccal teeth absent. Esophageal funnel greatly enlarged. Esophageal teeth not prominent. Anterior muscular portion of esophagus about ¼ to 1/3 of esophagus length. Excretory pore posterior to NR. Anterior deirids near middle of glandular esophagus.

Male: Dorsal ray with 6 branches. Ventral rays shorter than laterals. Dorsal lobe longer then lateral lobes. Externodorsal rays origin at junction of dorsal and laterals rays. Gubernaculum large, with large dorsal handle and ventral notch. Genital cone short, conical or elongate, extends beyond bursal edge. Spicule tips pick-shaped.

Female: Vulva about one, or less than one, tail length from anus. Ovejector vestibule oval or Y-shaped, infundibulum about equal to sphincter. Tail conical or digitiform, short, length less than 2x diameter at anus.

Type species: C. bicoronatus (Looss, 1900) Cram, 1924

Discussion

This genus was recognized by Ihle (1922) and Theiler (1923) as a subgenus. Both workers included C. bicoronatus, C. euproctus, C. ihlei, and Cylicocyclus ultrajectinus. Cram (1924) raised Ihle's subgenus to the rank of genus and included the same four species. Ershov (1943) and Popova (1958) expanded the genus Cylicodontophorus, including three of the above-mentioned four species (excluding C. ultrajectinus} and adding Cyathostomum sagittatum, Cyathostomum ornatum, Cyathostomum pateratum, and C. mettami. These Russian workers considered C. ihlei to be a junior synonym of C. mettami. K'ung (1964) considered the genus to have been improperly expanded and included only C. bicoronatus, C. euproctus, and C. mettami. Lichtenfels (1975) agreed with K'ung in this opinion. Dvojnos and Kharchenko (1988) have redescribed C. mongolica Tshoijo, 1957.Another species belonging to this genus, C. schuermanni (Ortlepp, 1962), is known only in zebras.

Hartwich (1986) removed all except the type species to a new genus, Parapoteriostomum. We agree with Hartwich’s (1986) restriction of Cylicodontophorus to species with the number of ILC and ELC elements about equal and with the ELC of broad pointed elements. We add to the single species retained by Hartwich, C. bicoronatus, a species not considered by Hartwich, C. reineckei Krecek et al., 1984).