Miljutin, D. M.; Tchesunov, A. V. (2001). On the histological anatomy of Benthimermis megala Petter, 1987, a giant nematode from the Norwegian deep-sea (Nematoda: Benthimermithidae). Nematology. 3(6), 491-502.
Miljutin, D. M.; Tchesunov, A. V
On the histological anatomy of Benthimermis megala Petter, 1987, a giant nematode from the Norwegian deep-sea (Nematoda: Benthimermithidae)
Free-living adult stages of Benthimermis megala Petter, 1987, the biggest species (body length 78 - 148 mm) of the genus, have been found in bottom sediments of the deep-sea off the Norway coast and studied histologically. The head region includes six subcuticular sensilla, four minute cephalic setae and pore-like amphids. Numerous tiny sensilla are distributed throughout the lateral sides of the body. An axial spine is present on the posterior body terminus. Hypodermal glands are associated with the somatic sensilla.
There are eight chords in the hypodermis. Mouth opening is absent. Vestigial pharynx is glandular and devoid of an internal lumen. Midgut is a trophosome made up of large radial cells and a very thin axial internal lumen. The trophosome cells are filled with various inclusions, which are reduced in size and number with age. A few cuticular grains are present in a vestigial rectum. The nerve ring is
embedded in the anterior trophosome.The female genital systemis amphidelphic.The germinal zone of the ovaries extends the length of the gonad (hologonic ovary), whereas the ovaries of smaller Benthimermis species are telogonic. Neither spermatozoa nor spermatheca in female ducts were identified. No males of B. megala were found. Obviously, larval stages parasitise benthic invertebrates, while
non-feeding adult stages dwell freely in sediment and reproduce.