NAME Gigasporites myriamyces
AGE Early Middle Triassic.   AGE span: 245.9...237 mya
K&J CLASSIFICATION (2000) Zygomycetes, Endogonales.
FIGURE(S)
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Pl.31fig.3.jpg
FIGURE REFERENCE Phipps CJ, Taylor TN. 1996. Mixed arbuscular mycorrhizeae from the Triassic of Antarctica; Mycologia, v. 88, p. 707-714.
SPECIES, AUTHORITY G. myriamyces Phipps & Taylor 1996, p. 709, fig. 7.
LOCATION Fremouw Peak, Antarctica, near the Beardmore Glacier.
ORIG DESCRIPTION* As for the genus [combined description].
COMMENTS* Hyphae and arbuscules are found evenly distributed throughout the cortex of the roots. Hyphae are irregular in thickness, occasionally characterized by swollen areas, and are extensively coiled within the cells. Hyphae average 6.3 µm in diameter, and branching is dichotomous. Septa are common, particularly at branching points, but septa are not continuous throughout the diameter of the hypha. One consistent feature of G. myriamyces is the absence of vesicles in association with hyphae.

Arbuscules are not confined to any distinct region of the cortex, and occur in various stages of deterioration. They occupy an average of 55% of the cell volume, with no observable size or shape differences for the cells containing arbuscules. The arbuscules of Gigasporites are robust and are characterized by thick trunks. Arbuscular branching is coarse, and usually can be determined only to the second order of branching. Several cortical cells appear to contain cross or slightly oblique sections of arbuscules at a low point of branching. Only one arbuscule is present within a single cell.
PUBLICATION REFERENCE Phipps CJ, Taylor TN. 1996. Mixed arbuscular mycorrhizeae from the Triassic of Antarctica; Mycologia, v. 88, p. 707-714.
K&J REMARKS
TYPE
ALL NAMES (Including synonyms) Gigasporites myriamyces
SERIAL NUMBER 639
PUBLIC COMMENTS
 *For source, see Publication Reference.