Calopadia imshaugii
Calopadia imshaugii is a species of crustose lichen in the family Pilocarpaceae. It was described from Florida. It has brown apothecia with a coarse, white coating, and its ascospores are often produced two per ascus, which is unusual in Calopadia.
Taxonomy
Calopadia imshaugii was described as a new species in 2011 by Ralph Common and Robert Lücking, based on material collected in Fakahatchee Strand Preserve State Park. The holotype was gathered in April 1997 along the Scenic Drive just past bend near gate 14 in second-growth habitat. It is deposited in the herbarium of the Michigan State University Museum.The species is named in honor of the American lichenologist Henry Imshaug. The species stands out within Calopadia because its asci can contain more than one ellipsoid ascospore, whereas most species in the genus have single-spored asci. Among the few multi-spored species, the spores are usually narrow and oblong rather than ellipsoid.
Description
The thallus grows on bark, typically 0.5–3 cm across and about 0.5–3 cm across and about 30–50 μm thick. It is continuous in the center but breaks into dispersed, irregular patches toward the edges. The surface is uneven and ranges from white to pale gray. The is a green alga with cells.The apothecia are rounded and , 0.4–0.8 mm in diameter. The disk is brown and coarsely white-pruinose, and the margin is conspicuous and pale gray to cream-colored. Microscopically, the excipulum is colorless and the hypothecium is brown ; the apothecial base is dull brown. The hymenium is colorless and about 100–130 μm high, with paraphyses that are unbranched to slightly branched.
The asci are about 90–100 × 20–30 μm and contain 2 ellipsoid, ascospores per ascus. The spores measure about 50–80 × 15–23 μm. The species also forms campylidia with a hood-shaped lobe that is dark gray with a paler apex and pruinose. The conidia are filiform with a clavate tip, 7–15-septate, and about 70–90 × 1.5–2 μm. All spot tests were negative.