• DOI:10.1080/00364827.1987.10419723
• Corpus ID: 83378553

New records, external and internal anatomy, and systematic position of Hansen's y-larvae (Crustacea: Maxillopoda: Facetotecta)

@article{Grygier1987NewRE,
  title={New records, external and internal anatomy, and systematic position of Hansen's y-larvae (Crustacea: Maxillopoda: Facetotecta)},
  author={Mark J. Grygier},
  journal={Sarsia},
  year={1987},
  volume={72},
  pages={261-278}
}

• M. Grygier
• Published 15 December 1987
• Biology
• Sarsia

Abstract Y-larvae comprise the crustacean taxon Facetotecta. A new kind of ‘nauplius y’, designated Type VI, is described from plankton in Disko Bay. West Greenland. The internal anatomy and some external features of ‘cypris y’ are described from a 2 μm-sectioned specimen collected in Oresund and from a whole-mounted specimen from Disko Bay. Newly discovered or reinterpreted features of ‘cypris y’ include: sessile compound eyes with tripartite crystalline cones; two pairs of eye-associated sensory organs which are homologized with the biramous, plumose cephalic organs found in some Ascothoracida; the antennular segmentation; identification of the ‘oral pyramid’ as the labrum with a posterior mouth and blind pharynx; sparse cephalic musculature except in antennules; first thoracic tergite shared by first two thoracomeres (first thoracomere not fused to head); a complicated array of basal thoracopodal sclerites; a solid oesophagus trace and no differentiated midgut (dorsal yolk or oil globules instead); a c...