Monographs Details: Campylopus angustiretis (Austin) Lesq. & James
Authority: Frahm, Jan-Peter. 1991. Dicranaceae: Campylopodioideae, Paraleucobryoideae. Fl. Neotrop. Monogr. 54: 1-238. (Published by NYBG Press)
Synonyms:Campylopus delicatulus R.S.Williams, Campylopus ditrichoides Broth., Campylopus ditrichoides var. robustior Broth., Campylopus leptodictyon Broth., Dicranum angustirete Austin, Campylopus gracilicaulis subsp. angustiretis (Austin) Kindb., Campylopus surinamensis var. angustiretis (Austin) J.-P.Frahm
Description:Species Description - Plants to 5 cm high, usually smaller, often only a few mm high, in loose mats. Stems usually not branched, equally foliate with conspicuous spreading leaves, the upper leaves dense, forming a comal tuft. Leaves 6 mm long, lanceolate, long decurrent, from an ovate base gradually narrowed into a fine point, denticulate at the extreme apex, keeled. Costae filling only 1/4 of the leaf base, excurrent, in transverse section with ventral hyalocysts smaller than the median deuter cells, with conspicuously thinner adaxial cell walls, dorsally with a narrow band of substereid cells, smooth at back. Alar cells large, inflated and widely auriculate, long decurrent. Basal lam- inal cells incrassate, elongate rectangular, often slightly pitted, 6-13 × 32-48 µm, narrower at margins. Upper laminal cells incrassate, elongate, 6-10(-l 2) times as long as broad, not sharply delimited from the basal laminal cells, 4-6 × 26-45 µm. Sporophyte not known.

Discussion:Campylopus delicatulus var. carolinae (Grout) Theriot, Mem. Soc. Cubana Hist. Nat. 15: 232, 1941 has nothing in common with C. angustiretis and is treated here as its own species, C. carolinae. Campylopus angustiretis differs from all other neotropic species of Campylopus by its narrow costa and elongate upper laminal cells. Since the sporophyte of this species is not known, it is placed tentatively in Campylopus and may ultimately have to be transferred to another genus.

As in Campylopyus carolinae, C. angustiretis is disjunct between SE North America and Brazil. Also the habitat of these species in both parts of their range is identical.

Campylopus angustiretis has been considered a variety of C. surinamensis. It resembles the "donnellii?" -expression of C. surinamensis in certain anatomical characters such as the long upper laminal cells and its habit that has stems ending in comal tufts. However, C. surinamensis has a broader costa (1/3 of the leaf base), shorter and wider basal laminal cells, a longer nerve that is excurrent into a coarsely serrate awn, a transverse section of the costa with ventral hyalocysts slightly larger than the median row of deuter cells, and more distinct groups of dorsal stereids. Furthermore, the leaves of C. angustiretis are distinctly keeled while the leaves of C. surinamensis are concave.
Distribution:Cuba South America| Piñar del Río Cuba South America| Santa Catarina Brazil South America| São Paulo Brazil South America|