I'm reading about a series of gutless worms described in several papers as phallodrilines. A search in the World Register of Marine Species shows that there is a subfamily called "Phallodrilinae", but then, in at least one paper this term is used to collectively describe gutless worms in several taxa including Oligochaeta, Annelida, and Clitellata. Since they're also described as club-headed I'm assuming that "Phallo-" is from the Latin for penis, but what would be the rest?
Phallus in Latin means penis, while drilus is the New Latin word for Greek
which means both worm or erect penis.
Here you can check some sources corroborating my claim:
-o- linking vowel indicates Greek.
-i- is Latin, unless the second word starts with a vowel (many
-ectomy words for example). This is irrespective of declension or gender. Weird I know.
In fact, Latin phallus is from φαλλός.
The second part is worm δρῖλος (drilos). Actually it can also mean penis, but let's gloss over that...