Relationships between Marimermithidae and Benthimermithidae:

• Originally, Marimermis, the type genus of the family Marimermithidae, and Trophomera (= Benthimermis Petter, 1980), the type genus of the family Benthimermithidae, were described together and placed in the same family Marimermithidae (Rubtsov & Platonova, 1974).
• Molecular data support morphology-based conclusions that the organisms represent two evolutionary independent lineages.

Life Cycle of Benthimermithidae:

•  as juveniles, benthimermithids parasitise the body cavity and internal organs of a variety of deep-sea benthic invertebrates
•  adults emerge from the hosts and do not feed but live on the nutrients stored during juvenile feeding
• the adults reproduce in the deep=sea environment
• since they do not feed, adult benthimermithid nematodes have no functioning mouth, their pharynx is vestigial, the midgut is transformed into a depository for nutrients stored to support the adult stage in the bottom sediment
• parasitic juveniles have a functional pharynx with a solid stick-like anterior structure, normal midgut, tail with a vestigial spinneet; sensilla appear to be absent in juveniles; lack of sensilla is considered related to the endoparasitic mode of life.
• sensory organs of benthimermithid adults, including papillae, setae and amphids are well developed.

Ref: Tchesunov and Rozenburg (2011)

Amphipod heavily infected by juveniles of Trophomera granovitchi (Benthimermithidae) from Tchesunov and Rozenburg, 2011

References:

Rubzov and Platonova (1974) erected the new family Marimermithidae including Marimermis together  with two other genera, Trophomera Rubzov & Platonova, 1974 and Thalassonema Ward, 1933, which were the only genera known at the time.

Miljutin, D. (2014). 7.10 Order Marimermithida Rubtsov 1980, emend. Tchesunov 1995. In. Schmidt-Rhaesa, A. (Ed.), Nematoda (pp. 345–350). Walter de Gruyter.

Tchesunov A.V., Rozenburg, A.I. 2011. Data on the life cycle of parasitic benthimermithid nematodes with the description of a new species discovered in marine aquaria. Russian J. Nematology 19:139-150.

Westerman, R., de Moura Neves, B., Ahmed, M. et al. (2021) Aborjinia corallicola sp. n., a new nematode species (Nematoda: Marimermithidae) associated with the bamboo coral Acanella arbuscula (Johnson). Syst Parasitol 98, 559–579

Return to Benthimermithidae Menu