28. Globulinella Steere, J. Wash. Acad. Sci. 36: 221. 1946.
[Genus Globulina and Latin -ella, diminutive]
Robert E. Magill
Seligeria subg. Globulina Müller Hal., Gen. Musc. Frond., 306. 1901, not Globulina Link 1820.
Plants small, in tufts or gregarious; dark green to golden brown or reddish brown. Stems 1-5 mm, simple or forked; scleroderm present, central strand well developed; axillary hairs short, with hyaline or light brown basal cell. Stem leaves appressed when dry, erect when wet, oblong-ovate to spathulate, obovate or orbicular, concave above, quickly tapering to base, margins entire to somewhat wavy, plane proximally, erect to broadly incurved above; apex broadly rounded, cucullate; costae single, ending below apex, frequently spurred above, distal adaxial cells quadrate to short-rectangular, enlarged and bulging above; in cross-section with single row of guide cells, adaxial cells similar in size to guide cells, somewhat thickened, abaxial stereid or substereid band well developed, epidermal cells somewhat larger, thickened; laminal cells smooth, rectangular, thickened, medial laminal cells rounded-quadrate, oblate or short-rectangular, smooth, thickened, distal cells quadrate to angular, thickened or incrassate, alar and marginal cells not differentiated. Specialized asexual reproduction by gemmae, rare, clavate to spherical, in leaf axils. Sexual condition dioicous. Perichaetia terminal, interior leaves little differentiated or somewhat sheathing. Seta elongate, red-brown, smooth. Capsule stegocarpous, theca oblong, operculum conic-rostrate; peristome teeth 16, cleft and irregular, erect from very short basal membrane. Calyptra small, cucullate, smooth. Spores 8-12 µm, round, weakly papillose. KOH laminal color reaction yellow.
Species 2 (1 in flora): North America, Central America, South America in temperate and tropical areas.
Globulinella can be recognized by its small stature, spathulate or oval leaves with broadly rounded, cucullate apex, and strong, laterally spurred costa ending below the apex. The plants grow in crevices or protected places on the sides of calcareous boulders or ledges. Gemmae have been reported by R. H. Zander (1993) from a Mexican collection.
Magill, R. E. 1977. A reexamination of Globulinella (Musci: Pottiaceae). Bryologist 80: 76-82.