Calyx is a term used in animal anatomy for some cuplike areas or structures.



Latin, from calyx (from Ancient Greek κάλυξ, case of a bud, husk").

The spicules containing the basal portion of the upper tentacular part of the polyp of some soft corals (also called calice).



A body part of the Entoprocta from which tentacles arise and the mouth and anus are located.[1]



The body disk that is covered with a leathery tegumen containing calcareous plates (in crinoids and ophiuroids the main part of the body where the viscera are located).[2]



Either a minor calyx in the kidney, a conglomeration of two or three minor calyces to form a major calyx, or the Calyx of Held, a particularly large synapse in the mammalian auditory central nervous system, named by H. Held in his 1893 article Die centrale Gehörleitung,[3] due to its flower-petal-like shape.[4]



In male insects, a funnel-shaped expansion of the basal part of the vas deferens (part of the seminal duct). Also in entomology, a flattened cap of neuropile in an insect brain (a component of the corpus pedunculatum) and by certain female insects, an expansion of the oviduct into which the ovarioles open.


  1. ^ R.C.Brusca, G.J.Brusca. Invertebrates. Sinauer Associates, 2 ed.(2003)
  2. ^ A.R.Maggenti et al., Online Dictionary of Invertebrate Zoology,, 2005
  3. ^ Held, H."Die centrale Gehörleitung" Arch. Anat. Physiol. Anat. Abt, 1893
  4. ^ Satzler, K., L. F. Sohl, et al. (2002). "Three-dimensional reconstruction of a calyx of Held and its postsynaptic principal neuron in the medial nucleus of the trapezoid body." J Neurosci 22(24): 10567-79.