Pilotrichum hypnoides (Hedw.) P.Beauv.

  • Authority

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

  • Family

    Pilotrichaceae

  • Scientific Name

    Pilotrichum hypnoides (Hedw.) P.Beauv.

  • Description

    Species Description - Plants small to medium-sized, in ± dull, yellow-green to golden patches. Stems creeping, with the leaves mostly eroded, the primary branches erect, 1.5-4 cm tall, mostly irregularly pinnate, sometimes regularly and densely pinnate; in cross-section with 46 rows of small thick-walled small-lumened colored cells surrounding larger firm-walled cells, central strand none; pseudopa-raphyllia filamentous; axillary hairs 2-celled, with a short brown basal cell and an elongate hyaline distal cell. Secondary branch leaves fairly crowded, erect when dry, erect-spreading when moist, ovate-lanceolate to oblong-lanceolate, 1-1.7 mm long, gradually to ± abruptly acute, concave, narrowly decurrent; margins serrulate almost throughout, subentire at extreme base, plane or incurved above, narrowly recurved below; costa double, equal, ± parallel most of its length, tapering distally, subpercurrent, with a medium-high crest 3-4 cells high; cells rounded-oblong, mostly conspicuously prorulose, thick-walled, ± porose, often shorter in the extreme apex and at basal margins, becoming longer and more conspicuously porose toward the insertion, insertion and decurrencies usually colored; alar cells not differentiated. Asexual propagula occasionally produced near base of costa (fide Crosby, 1969), not seen. Dioicous. Perichaetia conspicuous, on primary and secondary branches; leaves erect, lanceolate to ovate-lanceolate, 22.9 mm long, gradually acuminate, concave; margins distantly serrulate to subentire throughout, plane or sometimes narrowly recurved below; costa double, divergent most its length or parallel above, ending ca. 3/4 the leaf length, occasionally absent, not crested; cells linear, prorulose, thick-walled, porose, becoming shorter, thinner-walled, and unipapillose over the lumina toward the insertion. [Sporophytes not seen, the few details provided here fide Crosby, 1969: 334.] Setae 0.3-0.6 mm long; capsules immersed.

  • Discussion

    11. Pilotrichum hypnoides (Hedw.) P. Beauv., Prodr. Ae-théogam. 83. 1805; Neckera hypnoides Hedw., Sp. Muse. Frond. 203. 1801; Daltonia hypnoides (Hedw.) Am., Mém. Soc. Hist. Nat. Paris 2: 302. 1826; Callicosta hypnoides (Hedw.) Müll. Hal., Linnaea 21: 188. 1848. Plate 29, figure 11; plate 34, figures 7-10 Pilotrichum papillosum E. Britton ex H. A. Crum & E. B. Bartram, Bull. Inst. Jamaica, Sci. Ser. 8: 46. 1958, horn, illeg., non Broth., Akad. Wiss. Wien, Math.-Naturwiss. Kl., Denkschr. 83: 323. 1924 [= P. evanescens (Müll. Hal.) Crosby]. Discussion. Pilotrichum hypnoides is characterized by its oblong-lanceolate leaves with subpercurrent costae that narrow distally. The leaf cells are thick-walled but with the lumina wider than the cells, and usually strongly prorulose. Presumably the immersed capsules are also diagnostic but I have not seen them.

  • Distribution

    Range. Jamaica; growing on trees, in moist forests, at 1300-1800 m.

    Jamaica South America|