Entodon hampeanus C. Müll., New and Extinct in the United States

Abstract

Entodon hampeanus C. Miill., a Mexican-Andean moss, is reported for the first time from the United States. It was collected in Oconee County, South Carolina, in 1958, by Wilfred B. Schofield, but remained unidentified until recently. The creation of Lake Jocassee has since flooded the site and the moss is now extinct there. Nevertheless E. hampeanus can be added to a growing list of tropical American bryophytes that are disjunctive to the Southern Appalachian Mountains. A description and illustrations of the moss are provided. In June 1958, Wilfred B. Schofield collected a sterile Entodon in Oconee County, South Carolina, and referred it to the senior author for identification. In aspect the leafy plants resembled E. macropodus (Hedw.) C. Miill., except they seemed more slender and less complanate. Microscopically, the leaf shape looked vaguely different, and the alar cells seemed more prominent, but the differences were difficult to pinpoint. The absence of capsules made identification difficult. Schofield returned to the site in October 1959, and gathered a large quantity of the moss, enough, in fact, for future inclusion in the Crum and Anderson exsiccati, Mosses of North America. The plants were put aside with the provisional label, Entodon n. sp. The material did not surface again until 1982, when a specimen of the original sterile collection was sent to Buck, who had recently completed a generic revision of the Entodontaceae (Buck 1980). He suggested that it might be Entodon hampeanus C. Miill., a Mexican-Andean species not previously known north of Mexico, but lack of fruits prevented positive identification. Fortunately, when the exsiccati material was being packeted, it was found to be in fruit; it could then be identified with certainty as E. hampeanus. Meanwhile, Duke Power Company had constructed a huge dam on the Keowee River, into which the Whitewater River flowed at the time of Schofield's collection. This dam created Lake Jocassee, which flooded the site where E. hampeanus had been collected. In spite of many diligent searches it has not been found elsewhere. This paper, therefore, happily reports the discovery of a moss new to the United States and at the same time sadly takes note of its disappearance. Nevertheless, we call attention to the moss not only because of its phytogeographic significance but in the hope that it exists elsewhere in the Southern Appalachian Mountains and that it will be rediscovered. The accompanying description and illustrations should enhance the possibility of its being found elsewhere. ENTODON HAMPEANUS C. Miill., Linnaea 18: 705. 1845. (FIG. 1-10) Plants relatively slender, yellow-green, glossy, in flat mats. Stems elongate, to ca. 5 cm long, prostrate, irregularly branched, the branches complanate-foliate; pseudoparaphyllia foliose, narrowly lanceolate; axillary hairs uniseriate, with a single, short, brown basal cell and 3-4 elongate, hyaline, apical ones. Leaves oblong to oblong-ovate, to ca. 2 mm long, usually widest about 1/3 leaf length, acute or more often obtuse or broadly apiculate, concave, constricted at the insertion; margins plane, densely serrulate above, subentire below; costa short and double; cells linear, smooth, subflexuose, shorter at the extreme apex; alar cells numerous, not reaching costa or reaching it in only 2-3 rows, extending up margins in 5-9 rows, quadrate to short-rectangular, gradually differentiated from those above. Autoicous. Perichaetial leaves erect with gradually spreading apices, lanceolate, 1.3-2.2 mm long, gradually long-acuminate; margins plane, distantly serrulate above, entire below; ecostate; cells linear, subflexuose, becoming broader and shorter above; alar cells scarcely differentiated from other cells across insertion. Setae light yellow to yellow-orange, to ca. 2.5 cm long, twisted; capsules erect to somewhat nodding, cylindric, to 4 mm long; annulus not differentiated; operculum high-conic; peristome inserted well below mouth; exostome teeth reddish, lanceolate, on outer surface striate below, papillose 0007-2745/88/113-115$0.45/0 This content downloaded from 157.55.39.255 on Wed, 25 May 2016 05:55:09 UTC All use subject to http://about.jstor.org/terms 114 THE BRYOLOGIST [VOL. 91