The copulatory spicule
was described by Zunino (1972) as "spicola copulatrice" for the genus Euonthophagus Balthasar.
Small, length <5 mm, greatest height anterior and at posteroventral lobe; scleritome rough but glistening; epidermal sclerites rimmed, sharply pointed scales, flattened rods longer and thicker than scales, and a few rimmed, trowel-like sclerites with a short stem; copulatory spicule single, with a short sheath; glandular copulatory sac voluminous, filling the posteroventral body lobe; paired seminal vesicles each with two unusually large lobes and common duct; without seminal receptacles; lower gametoducts narrow, fused in distalmost portion and opening into mantle cavity.
Mantle cavity with scattered glands above epidermis; small, shallow, crowded by posteroventral body lobe containing copulatory spicule and sac.
A single copulatory spicule
was observed in one specimen.
The mantle cavity contains one or two gametopores, the anus, openings of the copulatory spicule sacs, and usually respiratory folds or papillae.
All drawings of sections have the following conventions: (1) double lines, no stippling, cell walls not indicated: gonopericardial ducts, seminal receptacles, copulatory spicule sacs; (2) single line: dorsal sinus, pericardium, heart; (3) double lines, stippling only: seminal vesicles; (4) double lines, cell walls, no stippling: upper gametoducts, rectum, mantle cavity; (5) double lines, stippling, cell walls: lower gametoducts.
Identification is based on the dimensions of the hooks and of the copulatory spicule
of males by using a microscope with a micrometric eyepiece (see Ali et al., 1984, 1985).
Pentastomids were identified based on the dimensions of hooks and copulatory spicules
of males (Almeida et al., 2008a; Ali et al., 1985).
Helicoradomenia is defined by its radula, type of ventrolateral salivary glands, body shape, types of sclerites, and presence of paired copulatory spicules
The long copulatory spicules
in the male worms, which measured approximately 1.2 mm (Figure 1B), are diagnostic for A.
Identifications were based on the dimensions of the hooks and copulatory spicules
of the males that were measured using a microscope equipped with an ocular micrometer.
Identification was based on the dimensions of the hooks and male copulatory spicules
(see Rego, 1983; 1984; Ali et al., 1984a; 1984b; 1985).