Pinnatella minuta (Mitt.) Broth.

Authority

Buck, William R. 1998. Pleurocarpous mosses of the West Indies. Mem. New York Bot. Gard. 82: 1-400.

Family

Neckeraceae

Scientific Name

Pinnatella minuta (Mitt.) Broth.

Description

Species Description - Plants small to medium-sized, in mostly dull, yellow-green or less often dark-green, lax to dense mats. Primary stems creeping, secondary stems arising from upturning primary stem, the creeping stem continuing by innovations near the base of the stipe, or secondary stems arising laterally, the secondary stems distinctly stipitate, to 10 cm tall but usually 1-4 cm, erect, irregularly 1-2-pinnate, complanate-foliate, stem apex frequently becoming flagellate and this becoming a primary stem; in cross-section with 4-5(-7) rows of small thick-walled cells surrounding somewhat larger firm-walled cells, central strand small; paraphyllia absent; pseudoparaphyllia foliose; axillary hairs with a 1(-2) short brown basal cells and 1-2(-3) elongate hyaline distal cells. Primary creeping stem leaves reduced, loosely appressed, ovate-triangular, 0.35-0.6(-0.7) mm long, broadly acuminate, ± decurrent; margins papillose-crenulate, plane or narrowly recurved below; costa single, ca. 3/4 the leaf length, sometimes projecting as a small prickle at apex; cells rounded-rhomboidal to short-rectangular, ca. 2-5:1, smooth or obscurely unipapillose, firm-walled; alar cells not differentiated. Stipes often short, well-differentiated leaves few, erect to laxly appressed, oblong-ovate, 0.7-1 mm long, acute to broadly acuminate, ± keeled, broadly short-decurrent; margins serrulate to papillose-serrulate above, crenulate below, plane or narrowly recurved below; costa single, ending ca. 7/8 the leaf length, sometimes projecting at apex, low-crested; cells small, ± isodiametric to 2:1, ca. 6-11 µm long, smooth or faintly unipapillose, especially above, firm-walled, becoming rectangular, ca. 4-5:1 toward the yellowed insertion; alar cells not differentiated in shape or size but distinctly seriately arranged. Secondary stem (continuation of stipe above branching) leaves complanate, turgidly erect-spreading, oblong-ligulate to oblong-ovate, ± symmetric, ca. 0.7-1(-1.5) mm long, acute, sometimes bluntly so, ± concave, short-decurrent; margins papillose-crenulate to serrulate above, crenulate to subentire below, plane or narrowly incurved below; costa single, ending ca. 7/8 the leaf length to subpercurrent and ending 3-7 cells below the leaf apex, sometimes projecting as a small spine at the apex; cells small, ± isodiametric, rounded-rhomboidal to rounded-hexagonal, 6-11 µm diam., smooth or more often (especially above) prorulose, sometimes unipapillose, firm-walled, becoming more elongate toward the yellowed insertion; alar cells ca. same size as laminal cells or slightly smaller, subquadrate to oblate, in obvious rows. Branch leaves mostly erect to erect-spreading, ± complanate, ± turgid, oblong-ovate, to ca. 0.6 mm long on 1o branches, to ca. 0.4 mm long on 2° branches, acute; other features as in secondary stem leaves. Asexual propagula of microphyllous, flagellate branches, arising singly or in groups from leaf axils. Dioicous. [Sporophytes unknown in the New World; description adapted from Enroth, 1994, based on African material.] Perichaetial leaves convolute below, ± spreading above, ovate, ca. 1.1 mm long, ± abruptly broadly long-acuminate; margins denticulate at apex, entire below; costa single, ending ca. 9/10 the leaf length. Setae short, mammillose above, smooth below, erect, yellow, 2-3 mm long, straight or slightly arcuate; capsules erect, cylindric, symmetric, 1.3-1.7 mm long; exothecial cells short-rectangular, firm-walled, becoming smaller toward the mouth; annulus not differentiated; operculum obliquely conic-rostrate, 0.6-0.65 mm long; peristome inserted below the mouth, pale, exostome teeth spiculose-papillose throughout, more strongly so on front surface, not trabeculate at back; endostome with a low basal membrane, segments spiculose-papillose, keeled, narrowly perforate, as long as the teeth, cilia none. Spores spherical, finely papillose, (10-) 12-15(-20) µm diam. Calyptrae seemingly campanulate, hairy (with paraphyses), smooth.

Discussion

1. Pinnatella minuta (Mitt.) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 857. 1906; Porotrichum minutum Mitt., J. Linn. Soc., Bot. 12: 465. 1869. Plate 44, figures 1-9 Pinnatella jamaicensis E. B. Bartram in Orcutt, Jamaica Naturalist 1: 17. 1928. Discussion. Pinnatella minuta is a small, beautiful moss. It is a short-stipitate, frondose plant with turgidly complanate leaves. The leaves are ± ligulate with a strong single costa. The laminal cells are quite small and isodiametric. Although appearing smooth on casual observation, the laminal cells are actually prorulose to unipapillose. Sporophytes are not known in the Neotropics. The plants are rather small and often grow in limestone areas of the West Indies. Therefore, due to the size of plants and inaccessibility of habitats, Pinnatella minuta is seldom collected. Although Puerto Rico is one of the very best collected islands in the Caribbean, hosting collectors as early as 1818 (C. Bertero), and intensively collected by W. C. Steere in 1939-1940, P. minuta has only been found once on the island, and that in 1988 (Buck & Sastre-De Jesús, 1989).

Distribution

Range. Mexico, Guatemala, and Costa Rica, Ecuador, central Brazil, Paraguay, central and southern Africa from the Ivory Coast to Tanzania, south to Angola and Natal Province, South Africa, Madagascar, Comoro Islands and the Mascarenes, India; Cuba, Jamaica, Hispaniola (Haiti and Dominican Republic), Puerto Rico; growing on tree trunks, especially toward the bases, and roots, commonly on limestone, in humid forests, at ca. 251000 m, most frequent at 200-400 m.

Mexico North America| Guatemala Central America| Costa Rica South America| Ecuador South America| Brazil South America| Paraguay South America| Ivory Coast Africa| Ghana Africa| Togo Africa| Benin Africa| Nigeria Africa| Cameroon Africa| Central African Republic Africa| Democratic Republic of the Congo Africa| Rwanda Africa| Burundi Africa| Tanzania Africa| Gabon Africa| Republic of the Congo Africa| Equatorial Guinea Africa| Angola Africa| Zambia Africa| Zimbabwe Africa| Namibia Africa| Botswana Africa| South Africa Africa| Madagascar Africa| India Asia| Cuba South America| Jamaica South America| Haiti South America| Dominican Republic South America| Puerto Rico South America|