zoothecahttp://www.oed.com/dictionary/zootheca_n%3Ftab%3Dmeaning_and_usezootheca, n.
Revised 2017

zoothecanoun

Now rare.
  1. 1852–
    (In algae, fungi, and various lower plants) a cell or other structure containing one or more zoospores; (in some colonial invertebrates) a sheath enclosing a zooid.
    1. 1852
      Antheridium, or Zootheca of a Sea-weed (Fucus serratus), containing phytozoa.
      J. H. Balfour, Class Book of Botany vol. I. iv. 349 (caption)
    2. 1861
      The antheridium..is filled at maturity with a number of minute cells, which have been termed zoothecæ.
      R. Bentley, Manual of Botany i. v. 376
    3. 1908
      Where the individual zoid is included in a hard covering, this may be known as zootheca.
      H. Osborn, Econ. Zoology iii. 50
    4. 2016
      When the juveniles reach about 1 mm, they leave the zootheca and start building a mucus tube attached to the main stem of the hydroid colony.
      T. N. Molodtsova et al. in S. Goffredo & Z. Dubinsky, Cnidaria, Past, Present & Future xxv. 403/2

Originally published as part of the entry for zoo-, comb. form

zoo-, comb. form was revised in June 2017.