Two new species of Oochoristica Luhe, 1898 (Eucestoda : Cyclophyllidea : Anoplocephalidae : Linstowiinae) parasitic in Ctenosaura spp. (Iguanidae) from Costa Rica and Mexico

Five species of Oochoristica, Oochoristica osheroffi Oochoristica gracewile yae, Oochoristica whitentoni, and 2 new species described herein have strob ilae longer than 200 mm, many secondary ovarian lobes, and testes extending anteriorly to midovarian level. A combination of 3 characters distinguishe s the 5 species from each other. Oochoristica osheroffi has an average of 6 8 testes per proglottid, ovarian lobes wider than long, and osmoregulatory canals not forming an anastomosing plexus; O. gracewileyae has an average o f 113 testes per proglottid, ovarian lobes longer than wide, and osmoregula tory canals not forming an anastomosing plexus; O. whitentoni has an averag e of 125 testes per proglottid, ovarian lobes wider than long, and osmoregu latory canals forming an anastomosing plexus; a new species in Ctenosaura s imilis from Costa Rica has an average of 62 testes per proglottid, ovarian lobes longer than wide, and osmoregulatory canals forming an anastomosing p lexus; and a new species in Ctenosaura pectinata from Mexico has an average of 122 testes per progottid, ovarian lobes longer than wide, and osmoregul atory canals forming an anastomosing plexus. Oochoristica gracewileyae diff ers from the other 4 species by having genital pores 10-15% rather than 25- 35% of proglottid length from the anterior end and by having convoluted rat her than straight or sinuous transverse osmoregulatory canals. The new spec ies from Mexico differs from the other 4 species and apparently from all de scribed species of Oochoristica thus far by possessing darkly staining gran ules throughout the parenchyma of the scolex.