Nephasoma (Nephasoma) ditadii Kawauchi & Rice 2009  

External anatomy

(From Kawauchi & Rice 2009)

Introvert extended from the center of anterior pseudoshield, no hooks on the introvert.

Elongate body marked by conspicuous constriction between base of the introvert and anterior part of the trunk.

Introvert one-half length of the trunk.

Introvert width averages 0.76 mm.

Trunk width averages 1.6 mm.

Ratio of length of trunk to width is 3:1.

The tentacle crown consists of at least 4 digital tentacles, and surrounds the mouth at the distal end of the introvert.

Pseudoshield encircles anterior trunk, has amber color and is composed of closely apposed polygonal or square plates fused, forming longitudinal ridges. Posteriorly individual plates become more defined and arranged as slender lines to the end of the posterior trunk.

Wart shaped papillae ranging from 12.5 to 15µm in diameter are scattered among plates of shield and trunk.

Internal anatomy

(From Kawauchi & Rice 2009)

Body wall has a continuous longitudinal muscle layer.

Two ventral retractor muscles, separated for most of the length and attached to the body wall on either side of the nerve cord at level one-third of trunk length from posterior end of body.

Gonad ridge (when present) is located near base of retractor muscles.

Two free nephridia, open to the exterior slightly posterior to the anus.

Intestine with about 16 or more coils, not attached to the posterior end of the trunk.