Eurhynchium clinocarpum (Taylor) Paris

  • Authority

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

  • Family

    Brachytheciaceae

  • Scientific Name

    Eurhynchium clinocarpum (Taylor) Paris

  • Description

    Species Description - Plants medium-sized to rather robust, in ± lustrous, mostly stiff, yellow-green mats. Stems creeping or ± arching, irregularly to subpinnately branched, the branches prostrate to ascending; in cross-section with 2-4 rows of small thick-walled cells surrounding larger ± thin-walled cells, central strand small but well developed, of small thin-walled nodulose cells; pseudoparaphyllia broadly foliose; axillary hairs with a single short brown basal cell and 1-2 relatively short hyaline distal cells. Stem and branch leaves differentiated, stem leaves distant, erect-spreading to spreading, ovate, 1-1.7 mm long, ± abruptly acuminate, the apex sometimes twisted, concave; margins serrulate throughout, plane; costa single, not tapering distally, ending 1/2-3/4 the leaf length, usually projecting at apex as a small spine, occasionally smooth; cells long-hexagonal to linear, smooth, thin-walled, not porose, becoming shorter toward the margins; alar cells scarcely differentiated, with a few, rectangular cells at extreme angles, not reaching the costa. Branch leaves ± distant, often ± complanate, erect- to wide-spreading, lanceolate-ovate to broadly ovate, 0.85-1.5 mm long, gradually or often ± abruptly acute or short-acuminate, concave, occasionally substriate; margins serrulate throughout, much more strongly so above, plane; costa single, bold, not tapering distally, ending 3/4-5/6 the leaf length, projecting apically as a prominent spine; cells long-hexagonal to linear, smooth, thin-walled, not porose, becoming short-hexagonal to rhombic apically, becoming shorter toward the margins; alar cells not differentiated but those all across the insertion rectangular, thick-walled, porose. Asexual propagula none. Synoicous, or occasionally polyoicous. Perichaetia inconspicuous; leaves numerous/perichaetium, spreading, oblong-ovate, to 2.4 mm long, abruptly long-acuminate, concave; margins serrulate above, entire below, plane to erect; costa none; cells linear, subflexuose, smooth, thin- to firm-walled, not porose, becoming shorter, broader, thicker-walled and porose toward the insertion; alar cells not differentiated. Setae elongate, stout, roughened throughout, reddish, 2-2.5 cm long, mostly straight, not or scarcely twisted; capsules inclined to horizontal, arcuate, asymmetric, short-cylindric with an indistinct neck, 2.2-2.8 mm long; exothecial cells hexagonal to short-rectangular, thick-walled, stomata round-pored; annulus of 2-3 rows of long-rectangular thick-walled cells, ca. the same size as those of the exothecium but narrower; operculum obliquely long-rostrate; exostome teeth reddish brown, triangular, shouldered, bordered, on the front surface cross-striolate below, with overlying fine papillae, finely and densely papillose at midtooth, coarsely papillose above, trabeculate at back; endostome finely and densely papillose, with a high basal membrane, segments keeled, broadly perforate or often gaping, ca. as long as the teeth, cilia mostly in groups of 3, short-appendiculate, shorter than the segments. Spores spherical, very finely papillose or almost smooth, 11-14 µm diam. Calyptrae cucullate, naked, smooth.

  • Discussion

    1. Eurhynchium clinocarpum (Taylor) Paris, Index Bryol. 442. 1896; Hypnum clinocarpum Taylor, London J. Bot. 7: 194. 1848; Brachythecium clinocarpum (Taylor) A. Jaeger, Ber. Thätigk. St. Gallischen Naturwiss. Ges. 1876-77: 327. 1878; Oxyrrhynchium clinocarpum (Taylor) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 1154. 1909. Plate 96, figures 1-10 Rhynchostegium rigescens Müll. Hal., Bull. Herb. Bois-sier 5: 566. 1897; Oxyrrhynchium rigescens (Müll. Hal.) Broth, ex Paris, Coll. Nom. Broth. 23. 1909, (Müll. Hal.) H. A. Crum & E. B. Bartram, Bull. Inst. Jamaica, Sci. Ser. 8: 61. 1958, comb, superfl. Discussion. Eurhynchium clinocarpum is distinguished by its ovate branch leaves with a strong costa. The leaves are less crowded than in E. pulchellum, and the stem can usually easily be seen between the leaves. One might confuse this species for a Platyhypnidium because of its broad branch leaves with acute to short-acuminate apices and short apical laminal cells. However, the costa is much more prominent in E. clinocarpum, it is synoicous, and has a rough seta. It differs from E. pulchellum in these last two characters as well. Because of the rough seta, it has been referred to Oxyrrhynchium, but I see no legitimate grounds for recognition of this genus, since many genera in the Brachytheciaceae can have either rough or smooth setae. I and several other bryologists, initially referred West Indian material to Eurhynchium remotifolium (Grev.) A. Jaeger. However, in the protologue of Hypnum remotifolium (Greville, 1826) the seta is described as smooth. Mitten (1869), though, gave it as rough, and this has been accepted to the present. There are two specimens in the Taylor herbarium (FH) that were sent to Taylor by Greville (B. Tan, pers. comm.). One, labeled “South America 1821,” probably represents type material: it has a single smooth seta but is missing the capsule. The other, collected by Gillies in 1843 (obviously not the type), has the seta slightly roughened at the extreme apex. Schwägrichen (1827: 170, 171, t. CC) described and illustrated the species as having a smooth seta. Therefore, although E. remotifolium has been used for a species with a rough seta, it appears that E. clinocarpum is the correct name for the taxon in question. West Indian material, were it universally sterile, would probably be assigned to Eurhynchium hians (Hedw.) Sande Lac. However, that north-temperate species is dioicous rather than synoicous. In the northern part of its range, E. Mans is a compact plant with closely placed leaves. However, material from southernmost Florida has the lax aspect virtually identical to that of E. clinocarpum. Unfortunately, all the material from Dade County, Florida, that I have examined is sterile, and so it is impossible to decide with certainty upon its identity. This problem is worth pursuing because there is a gap in the distribution of the taxon in Florida and one might be able to eventually sort material on the basis of geography, with northern Florida material assignable to E. Mans and southern Florida material to E. clinocarpum. Although I have not studied any material, from the description and illustrations in Sharp et al. (1994), it appears as if Eurhynchium semiscabrum E. B. Bartram may be an additional synonym of E. clinocarpum.

  • Distribution

    Range. Colombia, Ecuador, Peru, Guyana; Cuba, Jamaica, Hispaniola (Haiti and Dominican Republic); growing on moist soil, rocks or logs, often along streams, usually above 1000 m.

    Colombia South America| Ecuador South America| Peru South America| Guyana South America| Cuba South America| Jamaica South America| Haiti South America| Dominican Republic South America|