Monographs Details: Neckera
Authority: Buck, William R. 1998. Pleurocarpous mosses of the West Indies. Mem. New York Bot. Gard. 82: 1-400.
Scientific Name:Neckera
Description:Genus Description - Plants medium-sized to robust, mostly soft, in lustrous to dull, mostly pale-green (becoming yellowish in the herbarium), often large, epiphytic colonies, not stipitate-frondose. Primary stems creeping to projecting from substrate, irregularly frondose, secondary stems arising from upturning primary stem with creeping stem continuing by innovation, or secondary stems arising laterally from creeping primary stem, mostly erect, sometimes pendent, complanate-foliate; in cross-section with small thick-walled cells surrounding larger thinner-walled cells, central strand none; paraphyllia present or absent, sparse to abundant, filamentous to foliose; pseudoparaphyllia filamentous to foliose; axillary hairs with 1-2 short brown basal cells and 2-4 elongate hyaline distal cells. Branch and stem leaves similar or branch leaves much smaller, complanately disposed, erect to spreading, oblong-lanceolate to oblong-ovate, often asymmetric, obtuse to acute or acuminate, flat to strongly undulate, sometimes ± concave, often decurrent; margins entire to serrate, plane or recurved below, often on only one side; costa short and double or single to midleaf or higher, rarely absent; cells fusiform to linear, smooth, thin- to thick-walled, ± porose, shorter in the leaf apex; alar cells weakly differentiated to quadrate. Asexual propagula none. Autoicous or less often dioicous. Perichaetia conspicuous, without ramenta; leaves often greatly enlarged, mostly convolute, sometimes with spreading apices, narrowly to broadly oblong, gradually to abruptly short-acuminate; margins mostly subentire, sometimes serrulate above, plane; costa absent or short and single; cells mostly linear, smooth, thick-walled, ± porose. Setae short to elongate, smooth; capsules immersed to exserted, cylindric or rarely ± globose, erect and symmetric; exothecial cells quadrate to short-rectangular, firm-to thick-walled, not collenchymatous; annulus not differentiated; operculum short- to long-rostrate, straight to oblique; exostome teeth not bordered or shouldered, on the front surface ± cross-striolate below, smooth to papillose above or sometimes throughout, sometimes perforate, not or scarcely trabeculate at back; endostome rudimentary to ± well developed, the basal membrane low to medium-high, segments keeled, narrowly or not perforate, cilia none. Spores spherical, papillose. Calyptrae cucullate or rarely mitrate, naked or sometimes hairy, ± smooth.

Discussion:Neckera Hedw., Sp. Muse. Frond. 200. 1801, nom. cons., non Neckeria Scop., Intr. Hist. Nat. 313. 177 [Papaveraceae], nom. rej.; Eleutera P. Beauv., Mag. Encycl. 5. 1804, Prod. 30. 1805, nom. inval.; Eleuteria P. Beauv., Prodr. Aethéo- gam. 56. 1805, nom. inval. Cryptopodia Röhl., Deutschl. Fl., ed. 2, Kryptog. Gew. 3(1): 82. 1813; Neckera sect. Cryptopodia (Rõhl.) Limpr. in Rabenh., Rabenh. Kryptog.-Fl. Deutschl., ed. 2, 4(2 [Laubm. Deutschl.]): 698. 1894. Neckera subgen. Distichia Brid., Bryol. Univ. 2: 238. 1827, nom. illeg.; Distichia Brid., Bryol. Univ. 2: 787. 1827, nom. illeg.; Braunia Hornsch., Jahrb. Wiss. Krit. 1828(59-60): 467. 1828, nom. illeg., non Bruch & Schimp. in Bruch, Schimp. & W. Gümbel, Bryol. Eur. 3(fasc. 29-30, Monogr. 1): 159. 1846, hom, illeg. Omalia Lobarz., Naturwiss. Abh. (Vienna) 1: 48. 1847, nom. inval. Rhystophyllum Ehrh. ex E. Britton, Bryologist 8: 5. 1904. Discussion. Neckera is recognized in the West Indies by undulate leaves with acute to acuminate leaf apices. It differs locally from Neckeropsis by the pointed leaves and lack of ramenta in fertilized perichaetia. Additionally, Neckeropsis has more strongly asymmetric leaves with an indistinct border of elongate cells only on one side. However, the two Antillean species of Neckera approach Neckeropsis more closely than do some of the more temperate species of Neckera. For example, in Neckera pennata Hedw., type of the genus, the primary creeping stem turns upward to form the secondary stem. A creeping stem is continued by a bud giving rise to it near the base of the secondary stem. In Neckeropsis the erect portions are true branches, arising laterally from along the creeping stem. In this regard, both our Neckera species are like Neckeropsis. Similarly, Neckeropsis lacks stomata at the base of the capsule while most species of Neckera have them. Our two species lack stomata. For a final example, the exostomes of Neckeropsis are always papillose throughout. In Neckera exostomial ornamentation varies from basully cross-striolate to papillose throughout. One of our species is papillose with scarcely a trace of cross-striolae, and then only suborally. However, as emphasized above, the pointed leaves and nonramentose perichaetia characterize Neckera locally. Plants are almost always fertile. Rhystophyllum and Eleutera were used for Neckera at the beginning of this century because American authors did not accept Hedwig’s Species Muscorum as a starting point for moss nomenclature. They were following the American Code of Botanical Nomenclature (Arthur et al., 1907) where all priority was based on Linnaeus’s 1753 Species plantarían. Considering the convolutions of today’s International Code of Botanical Nomenclature, the American Code is appealing in its simplicity and lack of encumbrance with special interests trying to maintain favorite names. Early papers on North American Neckera (Stuntz, 1900; Britton, 1904) are worth studying for their historical perspective on plant nomenclature.