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Page number:48 
Description type:Non-original description 
Description:RAMARIA AMERICANA (Corner) Petersen, stat. nov. Basionym: Ramaria nigrescens var. americana Corner. 1950. Ann. Bot. Mem. 1: 608.[- Clavaria broomei auct. non Cotton & Wakefield. Coker, 1923. Clav. N. Amer. & Can., p. 186.] Type (lectotype): NCU - United States, New York, Vaughns, 12.viii.15, coll. Burnham, no. 74, annot. Coker, RHP [I] [illustrated: Coker, ibid., pl. 71 (lower), pl. 89, fig. 15]; (merotype - NY). Figures 4, 5.
Fruitbodies (Fig. 4) up to 7 cm high, up to 3 cm broad, branched, arbuscular. Stipe up to 50 x 5 mm, equal or tapering downward, white where protected, pinkish where exposed and/or handled, smooth, naked or with a few slender white rhizomorphic strands at very base; flesh white, unchanging on bruising or cutting. Branches arising as several denticulate cusps (cf. Coker, ibid., pl. 71, upper), elongating irregularly into a cristate to palmate pattern, finally with well developed apices, flattened, ochraceous brown to reddish brown when fresh, in age betoming reddish brown and blackening on drying (teste Coker, but not blackening on bruising or handling); axils narrowly rounded; young apices short, flattened-conical, the ends of the palmate or cristate branches, ochraceous to ochraceous tan; mature apices digitate to dichotomous, ochraceous tan; hymenium amphigenous, smooth, plushy. Odor and taste none (teste Coker).
Tramal hyphae of branches 1.5-3.0 µm diam, adherent, clamped, tightly parallel, yellowish in mass, thin-walled. Hymenium thickening; basidia 32-40 x 6.5-7.5 µm, clavate, pale
yellow in mass, (2)-4-sterigmate; sterigmata slender, straight, slightly divergent. Spores (Fig. 5) 14.5-22 x 5.5-7.5 µm (E = 2.24-3.60; _Em = 2.67; Lm = 16.25 µm), boletoid (cylindrical, with adaxial hump), deep reddish ochraceous in prints (teste Coker); contents homogeneous to obscurely multiguttulate; wall up to 0.5 µm thick, hilar appendix gradual, eccentric, often commashaped, thin-walled; ornamentation of discrete spines up to 2.5 µm long, occasionally connected into short plates, and these longitudinal.
Macrochemical reactions: not recorded.
On soil or leaf litter under Acer, Fagus and Tsuga; north eastern United States.
OBSERVATIONS: According to notes accompanying the portion of the type at CUP, both Peck and Coker knew of the taxon before its recognition as allied to R. macrospora (= R.
broomei). Peck considered it a form of R. grandis, and so described it (N.Y. St. Mus. Bull. 167: 24. 1913). Coker had received specimens from Burnham, and collected a few young fruitbodies with him (illustrated by Coker, 1923, as plate 71, above). Coker had intended to name the species after Burnham, but also wrote to Atkinson that he (Coker) had planned to call North Carolina collections CLavaria woodiana. Ramaria americana has never been seen from North Carolina, and I suspect that Coker had in mind either collections of R. longicaulis or more probably R. pancaribbea. Nevertheless, Coker finally become aware of the similarities between R. americana and CLavaria broomei, and published a description under the latter name.
The same notes at CUP also reveal a more precise topotype location. This taxon, and several others, were collected in Washington Co., NY, in the small village of Vaughns, in the forest owned by R.C. Burnham. Moreover, Atkinson stated (in MSS) "the main station for this species . . . is on the south bank of Glenwood brook, above the little waterfall, at or near the little outcrop of limestone before one reaches the first ledge going up the hill. [Burnham] no. 98, I believe grew on the north bank of Glenwood brook, somewhere near where the very large sugar maple stood toward the east end of the woods:'
Coker (ibid.) took this to be the same as R. macrospora (as Clavaria broomei), and paid little attention to the differences between the European and American fruitbodies. In fact, relying on spore dimensions and morphology, and fruitbody stature (net color), the two are very similar. Corner (1950: 608-609) relieved the situation, treating the American material as a separate variety (under R. nigrescens). Because I have placed more emphasis on basidial morphology and sterigmata number, I am obliged to remove the American specimens to a separate species on the following characters: 1) mostly 4sterigmate basidia; 2) tan to beige branch apices; 3) flesh color unchanging when bruised; 4) absence of bitter taste.
The last three characters come mostly from Coker's description and notes by Coker and Burnham. Nevertheless, the separation can be made on basidia alone.
When R. broomei and R. americana are separated, a closely related stirps can be identified, including R. broomei (q.v.) R. apiahyana, similar in color and spore morphology, and R. americana, with its intermediate basidia and tan branch tips. Superficially, the latter must resemble R. longicaulis, but microscopic characters differ. Nevertheless, the americana stirps presents real problems in segregating infrasubgenus groups on sterigmata number and/or basidial morphology.
In North America, the species is very restricted geographically, and has net been collected for years. A single specimen (n.v.) at NYS is from the same location as the NCU material. Inexplicably, however, virtually identical material has been examined from Japan (4-spores, fruitbodies similar, spores nearly identical) perhaps representing Ramaria cokeri (R. fragillima ss. Corner). Such a grographical disjunction is not unknown, but the taxon, inconspicuous on the forest floor, should be expected from intermediate areas.
There are variations in fruitbody stature and spore ornamentation over the geographic range of the taxon. Fruitbodies from North America tend to be sparsely branched, with the branches often gnarled or abortive, while those from Japan seem better developed, with many more branches and more prolonged internodes and apices. Spores of North American specimens are slightly narrower (reflected in higher Em values) but spores of Japanese specimens are more prominently ornamented. None of these variations seem to warrant separate taxonomic distinction, however.
 
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