The tegumental sensory organ and nervous system of Derocheilocaris typica (Crustacea : Mystacocarida)
Publikation/Tidskrift/Serie: Arthropod Structure & Development
A tegumental sensory organ is described in Derocheilocaris typica. It consists of sensory cells, the somata of which are situated in the rim of the central nervous system. They give rise to long dendrites, each of which transforms to one cilium. Three cilia surface in small pegs on the body. In the labrum there are seven peg sensilla with five and three with two cilia each that emerge in small pores into the atrium oris. The peg sensilla are distributed in a repetitious pattern on the body and labrum. A few pegs are found on some appendages. The cilia project through a distal pore to the environment. The mystacocarid type of tegumentary organ differs from that of the cephalocarids. The tegumental sensory organs may represent a new unimodal chemosensory organ within crustaceans. The central nervous system is described in detail including an electron microscopic analysis and our results are compared to an earlier light microscopic study. Nervous structures, not described before, are the stomatogastric nervous system, the abdominal ganglia, segmental nerves, a dorsal ganglion in the telson, and a 'neurohemal' organ in the thoracic ganglia. The brain organization is reinterpreted and it is characterized by its low degree of specialization.
- nervous system
- tegumental sensory organ
- ISSN: 1467-8039