Ontogeny and Identification of Life-Cycle Stages of Criconema octangulare (Cobb, 1914) Taylor, 1936.

The ontogeny of Criconema octangulare (Cobb, 1914) Taylor, 1936, is examined and shows ovary development and body length to be of primary importance in differentiating its life-cycle stages. Second-stage juveniles can be identified by body length and ovary length. The third stage can be distinguished from the second by longer body and ovary length, and from the fourth by a shorter ovary. The fourth stage can be identified by stylet length and ovary length. Included is a key to the life stages of C. octangulare, a description of the life-cycle stages, and light and scanning-electron microscopy illustrations.