Scolex of Paspalia macracantha; scolex of Ophryocotyle proteus; apical view of scolex of Fernandezia sp.; rostellum of Houttuynia sp.; hooks of Houttuynia strilionis. (Photos courtesy of A. Jones)

MORPHOLOGY: Small to large cestodes; proglottids usually numerous, rarely few. Rostellum usually present (rarely, rudimentary), small to enormous. Hook crown usually in 2 rows but may be in 1, 3, 5, or 10-12 rows. Hook crown usually round but may be oval or undulating, interrupted or not, or in form of cross with simple or bifid ends. Hooks characteristically numerous, tiny (rarely large), hammer-shaped. Accessory rostellar spines present or absent. Four suckers (absent in one genus), unarmed or armed with rows of minute spines. Genitalia single or double; when single, genital pores unilateral or alternate irregularly. Testes from two to hundreds, distribution variable. Cirrus-sac small to large, variable in extent relative to osmoregulatory canals. Ovary usually median, exceptionally poral, occasionally distinctly bilobed. Vitellarium compact, postovarian. Uterus persistent in gravid proglottids or replaced by paruterine organ or by egg-capsules containing 1 or several eggs. Four osmoregulatory canals (dorsal and ventral pairs), 2 (ventral pair only) or rarely 6 or 20.

DIVERSITY: Two subfamilies and about 37 valid genera recognized at present. About 500 nominal species.

PHYLOGENETIC RELATIONSHIPS: The Davaineidae is monophyletic. Cladistic analysis suggests that the nearest relatives include the Hymenolepididae, Dilepididae and the acoleid cestodes. Molecular phylogenies suggest a close relationship with the taeniids and paruterinids.

DEFINITIVE HOSTS: In birds and mammals.

SITE IN DEFINITIVE HOST: Intestine; once reported from lungs of ciconiiform birds (Satyanarayana).

GEOGRAPHIC DISTRIBUTION: Cosmopolitan.

LIFE-CYCLES: Two-host life-cycle. Larval stages in annelids, gastropods, and arthropods.

Selected References:

Artyukh, E. S. 1966. [Davaineata-tapeworms of wild and domestic animals]. Osnovy Tsestodolojii 6: 511 pp. [In Russian.] PDF

Jones, A. and R. A. Bray. 1994. Family Davaineidae Braun, 1900. In Keys to the cestode parasites of vertebrates, L. F. Khalil, A. Jones, and R. A. Bray (Eds.) CAB International, Wallingford, U.K., 407-444 pp. PDF

Hoberg, E. P., A. Jones, and R. A. Bray. 1999. Phylogenetic analysis among the families of the Cyclophyllidea (Eucestoda) based on comparative morphology, with new hypotheses for co-evolution in vertebrates. Systematic Parasitology 42: 51-73. PDF

Movsesyan, S. O. 2003. [Principles of Cestodology. Vol 13. Davaineates - tapeworms of animals and man.] Moscow: Akademiya Nauka, part 1, 261 pp; part 2, 395 pp. [In Russian.]