Maiaspora concava (M.A.Butterworth et R.W.Williams) D.A.Mamontov et D.McLean in Mamontov, McLean & Gavrilova

Plant Fossil Names Registry Number: PFN003301

Act LSID: urn:lsid:plantfossilnames.org:act:3301

Authors: D. A. Mamontov & D. McLean

Rank: species

Basionym: Microreticulatisporites concavus M.A.Butterworth et Ral.W.Williams

Genus: Maiaspora D.A.Mamontov, D.McLean, O.A.Orlova et O.A.Gavrilova

Reference: Mamontov, D. A., McLean, D. & Gavrilova, O. A. (2024): Maiaspora: the hallmark of gleichenioid ferns (Gleicheniales) from the early Carboniferous. – Papers in Palaeontology 10(3): e1561 (1–42).

Page of description: 13

Types

Original diagnosis/description

Size approximately 30-55 μm, outline triangular, apices broadly rounded, inter-radial margins concave; ornamentation finely microreticulate, distinct and regular. Rays extending for two-thirds radius.

Description. Spore coat thin, colour yellow. Inter-radial margins concave. Size of thirty-six measured specimens ranged from 32 to 52 μm; mean 40 μm; holotype 44 μm. Regular microreticulate ornament, lacunae approximately 2 μm in diameter, muri up to 3 μm wide, slightly arched, giving rise to a regularly notched margin. Rays straight, simple frequently torn.

Emended diagnosis

Spores radial, trilete, acavate, azonate, with triangular-concave amb; apices broadly rounded. Laesurae straight, simple, extending for two-thirds to fourth-fifths of radius. Exospore thick, covered with metareticuloid sculpture having coarse secondary ornament of verrucae, coni and tuberculae on the muri tips. Mean height of apiculate elements is >1 μm. Lumina are polygonal; scrobicula placed in the center of each lumen.

Stratigraphy

Carboniferous, Mississippian, Serpukhovian
Limestone Coal Formation, early Pendleian, Serpukhovian, Upper Mississippian

Locality

United Kingdom
Seam at 1872 ft 7 in Righead borehole, West Fife Coalfield, Scotland,