United States

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Populations of Argyrochosma limitanea represent two morphologically distinctive taxa treated here as subspecies. For the most part, these taxa have different geographic ranges, and genetic interaction between them is precluded because both are asexual triploids. Isozyme analyses indicate that the two subspecies have different polyploid origins, but evolutionary relationships (and proper taxonomic treatment) cannot be resolved until sexually reproducing (64-spored) progenitors are found.

Stem scales brown. Leaves 5--30 cm. Petiole reddish brown to black, 0.75--2 mm diam. Blade lanceolate to deltate, 3--5-pinnate proximally, leathery, abaxially covered by dense white farina, adaxially glabrous or sparsely glandular; rachis rounded to slightly flattened adaxially. Pinna costae straight to slightly flexuous, branches not arising from prominent angles. Ultimate segments not articulate, dark color of stalks continuing into segment bases abaxially; segment margins recurved, often concealing sporangia; veins obscure adaxially. Sporangia submarginal, borne on distal 1/2 of secondary veins, containing 32 spores.

Notholaena limitanea Maxon, Amer. Fern J. 9: 70. 1919; Cheilanthes limitanea (Maxon) Mickel; Pellaea limitanea (Maxon) C. V. Morton

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 1
Species: 1
Species With Barcodes: 1

United States

Rounded National Status Rank: NNR - Unranked

Rounded Global Status Rank: G4 - Apparently Secure