larval

from WordNet (r) 3.0 (2006)

larval
    adj 1: immature of its kind; especially being or characteristic
           of immature insects in the newly hatched wormlike feeding
           stage; "larval societies"; "larval crayfishes"; "the
           larval stage"
    2: relating to or typical of a larva; "the larval eye"

from The Collaborative International Dictionary of English v.0.48

larval \lar"val\ (l[aum]r"val), a. [L. larvalis ghostly. See
   {Larva}.] (Zool.)
   Of or pertaining to a larva.
   [1913 Webster]