Wittmann 1996a
Wittmann 1996a
WITTMANN, K. J., 1996: Morphological and reproductive adaptations in Antarctic meso- to bathypelagic Mysidacea (Crustacea), with description of Mysifaun erigens n.g. n. sp. In: F. UIBLEIN, J. OTT & M. STACHOWITSCH (Eds), Deep-sea and extreme shallow-water habitats: affinities and adaptations. - Biosystematics and Ecology Series, 11: 221-231.
http://www.oeaw.ac.at/kioes/biosystematics_e.htm
Among Mysidacea that frequently occur in 100-700 m depths in high-Antarctic regions, one finds special morphological adaptations in both sexes such as modified inner branches of the antennae, extremely large penes, or even glandiform structures. A species with erectile penes, previously unknown for the entire group of animals, is described as Mysifaun erigens n.g. n.sp. Females show no obvious peculiarities in primary sexual characteristics. High oil content and large size of the body are evident and interpreted as adaptive under conditions of strong seasonality in food supply. However, the Antarctic species appear to be in the lower size range when compared with a worldwide relation between body size and temperature. Extrapolations based on summer data suggest that the breeding cycle of a Mysidetes species corresponds to cold-season breeding as defined by WITTMANN (1984). The sexual morphological peculiarities are interpreted as being adaptive for males. They may have the chance to reproduce only once in their lifetime during a very short period. While it may be advantageous to bear highly efficient giant penes for mating, this may be inconvenient for normal activities such as swimming.
Antarctic; sexual morphological peculiarities; new taxa; biodiversity; sexual biology
Antarctomysis ohlini; Boreomysis brucei; Heteromysis sp.; Mysidella sp. A; Mysidetes sp. A; Mysidetes sp. B; Mysifaun nov. gen.; Mysifaun erigens noc. spec.; Paramblyops brevirostris