Hermaphroditic duct

The hermaphroditic duct is an anatomical structure in the reproductive system of many hermaphroditic gastropod mollusks, particularly among pulmonates and opisthobranchs. It serves as a conduit for gametes, transporting both sperm and ova from the gonad, commonly referred to as the ovotestis, to different regions of the reproductive tract.^[1][2]

Simplified diagram of the reproductive morphology of a pulmonate land snail.
AG = albumen gland
BC = bursa copulatrix
BT = bursa tract/trunk
BTD = bursa tract diverticulum
D = love dart
EP = epiphallus
FL = flagellum
FP = fertilization pouch
G = genital pore
HD = hermaphroditic duct
MG = mucous glands (nidamental gland)
OT = ovotestis
P = penis
PRM = penis retractor muscle
S = stylophore or dart sac (bursa telae)
SO = spermoviduct
SP = spermatheca
SRO = spermatophore-receiving organ (indicated in grey)
V = vagina
VD = vas deferens

Structure and function

In simultaneous hermaphrodites, such as many land snails and opisthobranchs, the gonad produces both eggs and sperm. These gametes enter a common channel, the hermaphroditic duct, which carries them toward a reproductive system region where they are either stored, matured, or further transported. This duct typically connects the ovotestis to secondary reproductive organs such as the albumen gland, spermoviduct, or copulatory structures.^[1][2]