Home Central American Mosses
Home
Name Search
Family List
Generic List
Species List
!Didymodon luridus Hornsch. ex Spreng. Search in The Plant ListSearch in NYBG Virtual HerbariumSearch in Muséum national d'Histoire naturelleSearch in Type Specimen Register of the U.S. National HerbariumSearch in Virtual Herbaria AustriaSearch in JSTOR Plant ScienceSearch in SEINetSearch in African Plants Database at Geneva Botanical GardenAfrican Plants, Senckenberg Photo GallerySearch in Flora do Brasil 2020Search in Reflora - Virtual HerbariumSearch in Living Collections Decrease font Increase font Restore font
 

Published In: Systema Vegetabilium, editio decima sexta 4(1): 173. 1827. (Syst. Veg. [Sprengel]) Name publication detailView in BotanicusView in Biodiversity Heritage Library
 

Project Name Data (Last Modified On 2/15/2011)
Acceptance : Accepted
Project data     (Last Modified On 2/15/2011)
Discussion:

This species has long been known as Didymodon trifarius (Hedw.) Roehl. The type of that species, however, actually represents Saelania glaucescens (Hedw.) Broth. (see Zander 1978a). Didymodon luridus is a small species with short-lanceolate, ovate-lanceolate, or triangular-lanceolate leaves that have obtuse or broadly acute apices, smooth to weakly papillose leaf cells, and a broad costa that ends well below the apex. There is a Guatemalan collection (Standley 65640, F) that fits uncomfortably in D. luridus because its leaf cells are somewhat large, extremely irregular in shape and at times unipapillose.

In most of its features D. luridus closely resembles D. tophaceus, and most Central American reports of D. tophaceus are instead D. luridus. Didymodon luridus differs from D. tophaceus in having quadrate instead of elongate cells on the upper ventral surface of the costa and not to slightly decurrent leaves. The last feature, however, is not always reliable in separating the two species since according to Zander (1998) long leaf decurrencies are absent from a large percentage of D. tophaceus collections. Didymodon nigrescens is similar to D. luridus in having obtuse to broadly rounded leaves, short costae, and quadrate cells on the upper ventral surface of the costa. It differs from D. luridus in its consistently reddish yellow color, lack of a stem central strand, leaves with long, bulging decurrencies, and costae that are more or less homogeneous in cross-section.

The world distribution of D. luridus is difficult to determine because the species has been  confused with other Didymodon species. For example, Zander (1981), citing specimens from Washington, Arizona, and California, attributed western North America to its range. But, he later (1993, 1998) excluded it from North America north of Mexico and considered all reports of D. luridus from the area to be D. brachyphyllus (Sull.) Zand., D. nicholsonii Culm, D. tophaceus, or D. vinealis.

Illustrations: Bartram (1949, Fig. 54 A–D, as D. tophaceus); Smith (1978, Fig. 122 1–6, as D. trifaria); Zander (1981, Pl. 5 5); Sharp et al. (1994, Fig. 235); Ku_era (2000, Fig 13). Figure 26.
Habitat: Damp or wet shaded banks and soil; 1780–2550 m.
Distribution in Central America: GUATEMALA. Huehuetenango: Standley 82407 (F); Quezaltenango: Steyermark 34985 (F).
World Range: Southwestern U.S.A.; Mexico; Central America; Caribbean; Northern, Middle, East, Southwestern, and Southeastern Europe; Caucasus, Middle Asia, Mongolia, China, Western Asia, Arabian Peninsula; Northern Africa.

 

Export To PDF Export To Word

Didymodon luridus Hornsch. in Spreng., Syst. Veg. 4: 173. 1827.

Didymodon trifarius var. luridus (Hornsch.) Mont., Arch. Bot. (Paris) 1: 139. 1833. Trichostomum luridum (Hornsch.), Spruce, Ann. Mag. Nat. Hist. Ser. 2, 3: 379. 1849. Barbula lurida (Hornsch.) Lindb., Musci Scand. 22. 1879. Didymodon vinealis var. luridus (Hornsch.) Zand., Cryptog. Bryol. Lichénol. 2: 412. 1981. Protologue: Germany. Ager bipont. Germ. 

Plants small, dull, green to yellow-green above, brown below, at times reddish yellow, in tufts 5–15 mm high. Stems yellow to reddish yellow, erect, sparsely and irregularly branched,  sclerodermis weakly present, central strand present; rhizoids sparse, at base of stems. Axillary hairs 5 cells long, basal 3–4 cells brown. Leaves 0.7–1.6 mm long, short-lanceolate to ovate-lanceolate, or triangular-lanceolate, spreading at base, erect-incurved when dry, spreading when wet, grooved along the costa on ventral surface; apices rounded obtuse to broadly acute; lamina unistratose or occasionally bistratose along the costa above; margins entire, recurved or reflexed to midleaf, plane above; costa subpercurrent, surface ventral cells of costa quadrate, guide cells present, dorsal stereid band poorly developed, ventral stereid band absent, ventral and dorsal surface cell layer enlarged; upper and basal cells smooth or weakly papillose, weakly differentiated, upper cells rounded, oblate or oblong 6–10(–17) x 4–12 μm, thick-walled, basal cells oblate, quadrate, round, triangular or short-rectangular, firm-walled, 6–28 x 6–8 μm, extreme basal cells enlarged, alar cells not differentiated. Dioicous. Perichaetia. Setae smooth, 8–10 mm long, red to reddish orange. Capsules ellipsoid to sub-cylindrical, erect, 1.0 mm long, smooth; exothecial cells short-rectangular, firm-walled; stomata in neck; opercula obliquely rostrate, 0.5 mm long; peristome red-orange, short, erect. Spores 8–12 μm, smooth. Calyptrae cucullate.

 

 
 
© 2024 Missouri Botanical Garden - 4344 Shaw Boulevard - Saint Louis, Missouri 63110