In Stanek's ( 1958 ) infrageneric concept, " G . pectinatum " is placed in section " Perimyceliata " ( encompassing species whereby the mycelial layer covers the entire endoperidium ), in subsection " Glabrostomata ", which includes species with plicate peristomes.
42.
The curtailment of habitat and range for this species ( and a few other snail species ) in the Mobile Basin's larger rivers-( Black Warrior River, the Little Warrior River, and the Tombigbee River for the Plicate rocksnail ) is primarily due to extensive construction of dams, and the subsequent inundation of the snail's shoal habitats by the impounded waters.
43.
It is medium to large sized, hot to warm growing terrestrial with close set, small pseduobulbs enveloped by leaf sheaths and carrying 5 to 6, elliptic, acuminate, plicate, gradually narrowing below into the elongate petiolate base leaf that blooms in the apring on a 20 to 24 " [ 50 to 60 cm ] long, erect, densely 40 to 60 flowered, racemose inflorescence with large, lanceolate, acute, very concave floral bracts that fall before the odorless flowers open
44.
They are characterized by round-section root with thick velamen, four-angled fleshy pseudobulbs of one internode, often basally protected by dried sheaths and with only one apical leaf ( except for " Bifrenaria steyermarkii ", which occasionally has two ), plicate ( fan-folded ) enervated leathery leaves, yet malleable and not exceedingly thick, with a pseudo-petiole of basal round section, and a basal inflorescences bearing up to ten flowers, which seldom surpass the leaves'length.
