4. Homaliadelphus Dixon & P. de la Varde, Rev. Bryol. n. s. 4: 142. 1932. • [Genus Homalia and Greek adelphos, brother, alluding to similarity].
Homaliopsis Dixon & P. de la Varde, Ann. Bryol. 1: 48. 1928, not S. Moore 1920 [Myrtaceae] Inés Sastre-De Jesús
Plants small, shelf-forming, pale green to yellowish green, glossy. Stems creeping, sparsely branched to irregularly pinnate; paraphyllia present. Stem and branch leaves wide-spreading, obovate to nearly rounded, slightly asymmetric, flat, small lobe at adaxial base of lateral leaves; margins entire or slightly denticulate, teeth not recurved; apex rounded; ecostate or costa double, short; basal laminal cells short-rhomboidal, walls porose. Sexual condition dioicous (male plants epiphytic on female plants); perichaetial inner leaves oblong. [Seta 0.4-0.6 cm. Capsule oblong-cylindric; exostome teeth lanceolate, smooth to slightly striate basally; endostome basal membrane low, segments weakly papillose. Spores 15-20 µm].
Species 2 (1 in the flora): e United States, s Mexico, Asia (China, India, Japan).
Homaliadelphus is easily distinguished from other members of Neckeraceae by the characteristic adaxial basal leaf lobes. In North America this genus is restricted to calcareous rock, although in India the plants occur as epiphytes. Homaliadelphus targionianus (Mitten) Dixon & P. de la Varde is known from Japan.