A pantropical genus of seven species, two of which are African and three Asian; two species in the Neotropics, P. densa (Hook.) W. R. Buck (Mexico, Central America, tropical Andes, southeast Brazil) and P. pringlei (Cardot) W. R. Buck (Mexico, northern Central America). The genus is characterized by erect leaves, slightly enlarged decurrency cells, entire to finely serrulate margins, smooth laminal cells, numerous alar cells, erect, symmetric capsules, rather high basal membrane with flat, narrow segments and absence of cilia. Platygyriella densa is characterized by the soft, rather delicate plants, ovate-lanceolate leaves less than 1.2 mm long, gradually long acuminate apex, short but distinct leaf decurrencies, entire to finely serrulate margins, few to several quadrate to short rectangular alar cells.
Un género pantropical con siete especies, dos de las cuáles son africanas y tres asiáticas; dos especies en el Neotrópico. Platygyriella densa carácterísticas de esta especie las plantas suaves, bastante delicadas, con hojas ovado-lanceoladas menores hasta 1.2 mm de largo, ápices gradualmente largo-acuminados, decurrencias de las hojas cortas pero conspicuas, márgenes enteros hasta finamente serrulados, pocas hasta varias células alares cuadradas hasta corto-rectangulares.