Turbellarian taxonomic database

Isodiametra earnhardti Diagnosis

Hooge MD & Smith JPS 2004 (citation). Examined specimens 350 to 650 µm long and ~125 µm wide (Figs.6A, B, 7A,
8A). Body cylindrical.  Anterior and posterior ends rounded. Epidermis completely ciliated.  Body without
coloration in transmitted light, but gut contents green in color. Many mucoid glands present; arranged in
distinct rows.

Body-wall musculature with circular muscles that encircle the body along entire length of animal; straight
longitudinal muscles present between frontal organ and anterior edge of mouth; longitudinal muscles with a
longitudinal orientation anteriorly that bend medially to cross diagonally over the body
(longitudinal-cross-over fibers present in dorsal and ventral body walls; longitudinal muscles in the
anterior half of body that wrap around the posterior rim of mouth (U-shaped muscles) present in ventral body
wall (Fig. 8A). 

Frontal organ well developed; cell bodies of frontal glands positioned ~100 µm behind frontal pore (Fig. 6B).

Mouth opening on ventral surface, middle of body.  Digestive central syncytium extends from frontal glands
posteriorly to level of male copulatory apparatus.

Ovaries paired, ventral; extend from frontal glands posteriorly to bursal nozzle (Fig. 6B). Testes paired,
lateral to eggs, compact; separate from ovary.  Testes extend from level of statocyst  posteriorly to level
of bursal nozzle. Common  genital pore opens posteriorly to male copulatory apparatus and anteriorly to
vagina (Figs. 6, 7B, C). Vagina positioned somewhat to the right side of male copulatory organ, rather than
directly anteriorly.  Vagina filled glandular secrections in the form of tear drop-shaped clusters of
granules.  Vagina surrounded by thick muscular sphincter (Figs. 6, 7, 8B).  Walled seminal bursa leads to
well-developed bursal nozzle (Figs. 6, 7B, C). Gonopore opens directly to well-developed penis (Figs. 6C,
7C).  Slightly curved penis with outer longitudinal and inner circular muscle fibers that surround lumen
filled with spherical clusters of granular gland secretions (Figs. 6A, 7B, C, 8C).  Proximal end of penis
somewhat bulbous.  Penis invaginated into muscular seminal vesicle filled with sperm that surrounds proximal
end of penis. 

[From Hooge MD, Smith JPS (2004)]

Diagnosis for the valid (accepted) taxonomic name

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