Vascular Plants of the Gila Wilderness

Family: Aytoniaceae

Status: Native

Synonyms:
None

Mannia paradoxa was described by R.M. Schuster in 1982 from a specimen collected on the slope of Rattlesnake Canyon in Carlsbad Caverns National Park in New Mexico. The plant resembled Reboulia in many respects (thallus morphology and texture, dark lunate ventral scales with elongate appendages). However, it was smaller and the immature carpocephala were not lobed. He was unable to identify mature carpocephala. The plants were paroecious.
We searched the area of Rattlesnake Canyon where this species had been found growing with Selaginella and Plagiochasma. We collected numerous specimens under permit, all of which turned out to be Plagiochasma wrightii. No Mannia paradoxa was identified.
We then contacted Matt von Konrat at the Field Museum in Chicago where Schuster's collection resides. He was gracious enough to send us the entire type specimen, which we examined at length. Although the specimen was some 37 years old, we were able to confirm many of Schuster's observations. When dry, the thalli are curled up into small, tight black tubes. After lengthy rehydration, the thick thalli which have very conspicuous pores are indeed noticably smaller than those of Plagiochasma. The immature carpocephala, which are very numerous, are apical in location and almost granular in appearance with no lobe formation. Ventral scales are very difficult to dissect intact, but several elongate, curled appendages similar to those in Schuster's drawings were identified.
Mannia paradoxa is only known from Schuster's one collection-- it has not been recorded since and is not known from any other location.
Please click on an image for a larger file.

We are indebted to Matt von Konrat and the Chicago Field Museum for allowing us to photograph the original Schuster type collection.

Mannia paradoxa, collection by R.M. Schuster at Carlsbad Caverns National Park (Rattlesnake Canyon) dated 20 Jan 1982, photo Karen Blisard & Russ Kleinman, photographed May 27, 2019

Mannia paradoxa, closeup of rehydrated thalli and gynoecium, collection by R.M. Schuster at Carlsbad Caverns National Park (Rattlesnake Canyon) dated 20 Jan 1982, photo Karen Blisard & Russ Kleinman, photographed May 27, 2019

Mannia paradoxa, closeup of rehydrated thallus and gynoecium, collection by R.M. Schuster at Carlsbad Caverns National Park (Rattlesnake Canyon) dated 20 Jan 1982, photo Karen Blisard & Russ Kleinman, photographed May 27, 2019

Mannia paradoxa, closeup of rehydrated thalli and gynoecium, collection by R.M. Schuster at Carlsbad Caverns National Park (Rattlesnake Canyon) dated 20 Jan 1982, photo Karen Blisard & Russ Kleinman, photographed May 27, 2019

Mannia paradoxa, closeup of dry thalli and gynoecium, collection by R.M. Schuster at Carlsbad Caverns National Park (Rattlesnake Canyon) dated 20 Jan 1982, photo Karen Blisard & Russ Kleinman, photographed May 27, 2019

Mannia paradoxa, photomicrograph of pore, collection by R.M. Schuster at Carlsbad Caverns National Park (Rattlesnake Canyon) dated 20 Jan 1982, photo Karen Blisard & Russ Kleinman, photographed May 27, 2019

Mannia paradoxa, photomicrograph of pore, collection by R.M. Schuster at Carlsbad Caverns National Park (Rattlesnake Canyon) dated 20 Jan 1982, photo Karen Blisard & Russ Kleinman, photographed May 27, 2019

Mannia paradoxa, photomicrograph of cross sections of thallus, collection by R.M. Schuster at Carlsbad Caverns National Park (Rattlesnake Canyon) dated 20 Jan 1982, photo Karen Blisard & Russ Kleinman, photographed May 27, 2019

Mannia paradoxa, photomicrograph of scale appendage, collection by R.M. Schuster at Carlsbad Caverns National Park (Rattlesnake Canyon) dated 20 Jan 1982, photo Karen Blisard & Russ Kleinman, photographed May 27, 2019