October 22 - Lophoura brevicollum

Lophoura brevicollum is a parasitic copepod that infects the smooth grenadier Nezumia liolepis, a deep sea fish that is found in the bathypelagic depths, about 1200 metres (about three-quarters of a mile) down off the coast of Sinaloa, Mexico. The anterior of the parasite forms an anchor-like holdfast that is embedded in the back of its fish host. One of the more unusual morphological features of this parasite is a pair of peculiar tassels protruding from the abdomen, just in front of its elongated egg sacs. The function of these tassels is possibly related to the habitat of its host. Because L. brevicollum is an ectoparasite, it is exposed to the same environmental conditions as its fish host. In this case, it is the cold, dark surroundings of the deep sea. It has been suggested that the exotic brush-like protrusions of the copepod are adaptations to limited oxygen availability. The protrusions increase the copepod's body surface area to enhance oxygen uptake in the oxygen-poor environment of the bathyal zone.

Reference:
Gomez, S., Deets, G.B., Kalman, J.E., Morales-Serna, F.N. (2010) Lophoura brevicollum n. sp. (Copepoda: Siphonostomatoida: Sphyriidae), a parasite of the smooth grenadier Nezumia liolepis (Gilbert, 1890) (Pisces: Macrouridae) from the Eastern Pacific, and a new record and new host of Lophoura unilobulata Castro R. and Gonzalez. Journal of Crustacean Biology 30(1): 129-140.

Contributed by Tommy Leung.