Monographs Details: Glandulataenia
Authority: Stevenson, Dennis W. 1990. Morphology and systematics of the Cycadales. Mem. New York Bot. Gard. 57: 8-55.
Description:Genus Description - Leaves elongated, entire, showing a strong midrib persistent up to apex; lamina arising from the side of the midrib, lateral veins arising at a wide angle or at smaller angles but almost immediately bending outwards and crossing the lamina at a wide angle. Lateral veins occasionally forked, anastomoses between lateral veins extremely rare, interstitial areas showing rows of characteristic rounded dots (glands). Leaves hypostomatic, stomata haplocheilic, usually confined to areas between veins, subsidiary cells irregular, not forming a definite ring.
Discussion:Glandulataenia, gen. nov. Type species: G. glandulata (Srivastava), comb. nov.
The genus Glandulataenia can be distinguished from the older segregates of Taeniopteris Brongniart like Nilssoniopteris vittata, Nilssonia, Doratophyllum Harris, Bjuvea Florin and M. paniophyllum Sahni and Rhabdotaenia Pant, by the presence of interstitial rows of glands but it comes closest to Rhabdotaenia. Leaves of Glandulataeia whose epidermal structure is preserved show that the glands are present in the upper epidermis. The genus can be distinguished from other segregates by the same features as mentioned for Rhabdotaenia by Pant (1958) and Pant and Verma (1963). Although Chandra (1974) has stated that "Pant did not give any reasons as to why he instituted a new genus instead of retaining the original genus Macrotaeniopteris'" and doubted the distinction between Rhabdotaenia and Macrotaeniopteris, Pant (1958) had clearly pointed out that the type of the ill defined genus Macrotaeniopteris had been proved to be bennettitalean.
O n the basis of the similarity of the cuticular and epidermal structure of Rhabdotaenia with that of Glossopteris and their occurrence in Lower Gondwana beds. Pant (1958) and Pant and Verma (1963) had suggested that the two genera were possibly related, but the same cannot be said about Glandulataenia and its affinities are for the present uncertain.
Leaves assignable to Glandulataenia were earlier described by Srivastava (1971) under the name Taeniopteris glandulata and these are here assigned to the new genus on the basis of their characteristic glands and also the cuticular structure of identical leaves in our collection. However, glandless leaves which Srivastava (1976) assigned to Gopadia are just like those of Rhabdotaenia but distinguished from it merely by the absence of cross connections. They should be transferred to Rhabdotaenia since anastomoses between lateral veins are extremely rare even in Rhabdotaenia and the genus Gopadia should therefore, be regarded as a synonym of Rhabdotaenia.