We don't have synonyms for endophallus yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are endophyllous and endophagous.
(n) :
(zoology) The inner wall of the aedeagus of an insect, derived during embryological development by the fusion of paired genital papillae to form a medial tube. The endophallus is eversible and flexible, is the actual intromittent organ, and sometimes has backward-orientated denticulations to achieve a firm hold on the vaginal walls of the female.
(n) :
(zoology) The inner wall of the aedeagus of an insect, derived during embryological development by the fusion of paired genital papillae to form a medial tube. The endophallus is eversible and flexible, is the actual intromittent organ, and sometimes has backward-orientated denticulations to achieve a firm hold on the vaginal walls of the female.