COLLECTIONS: All from North Island: site 20 (type locality), 12, and 19.

Trichospores elongate-ellipsoidal, almost cylindrical, 39-50 x 6-8 µm, with two broad appendages circa 20 µm long and one very fine appendage many times the length of the trichospore. Thallus initially sparsely branched, becoming densely branched with up to 15 generative cells per fertile branch. Holdfast a bulbous, sometimes striated growth from the main branch. Zygospores unknown. In Plecoptera nymphs.

HOSTS: In addition to Z. decorata, host's of G. plecopterorum included Z. fenestrata Tillyard and Acroperla spiniger (Tillyard) (Gripopterygidae).

Trichosporae elongato-ellipsoideae, subcylindricae, 39-50 x 6-8 µm, appendiculis duobus latis circa 20 µm longis, tertio multipliciter quam trichosporae longiore. Thallus primo sparse ramosus, demum dense ramosus, cellulis genitalibus numero ad 15 in ramo fertili gestis. Tentaculum ab excrescentia bulboua, interdum striata, e ramo principals constitutum. Zygosporae ignotae. In nymphis Plecopterorum.

The most unusual feature of G. plecopterorum is the stonefly host; the two other currently described species of Glotzia, as well as another one we will describe from Tasmania, occur in mayfly nymphs. Two other species of Glotzia have been described: G. centroptili Gauthier ex Manier & Litchwardt, known only from France, and G. ephemeridarum Lichtwardt, from Utah and Montana, U.S.A. The trichospores of G. plecopterorum (39-50 x 6-8 µm) most closely resemble those of G. ephemeridarum. The latter measure 45-70 x 4.5-7 µm, according to the emended trichospore diameter given by Lichtwardt (1986) (originally 4.5-5.0 µm (Lichtwardt 1972)). Although the size ranges of the two species overlap at their extremes, the trichospores of G. plecopterorum have a lesser average length to width ratio, resulting in an obviously different shape and average size. A more striking difference between these two species can be found in the mature basal cells. In G. plecopterorum, that cell is bulbous, but in G. ephemeridarum, the basal cell is tapered and studded with rows of lateral holdfast structures that anchor the thalli to the hindgut cuticle (see Lichtwardt, 1972, Fig. 47). A comparison of zygospores in the two species is not currently possible, because they are not known in G. plecopterorum.

HOLOTYPE: Slide ZEA 20-3 prepared from the hindgut of Zelandoperla decorata Tillyard nymph (Plecoptera, Gripopterygidae) obtained from Mangatoetoenui Stream, North Island, 18.VII.83 (site 20).
ISOTYPE: Slide ZEA-202-5 prepared from same host species and site. Both types deposited with R. W. Lichtwardt, University of Kansas.