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Page number:1790 
Description type:Non-original description 
Description:Ramaria obtusissima (Pk.) Corner, 1950. Ann. Bot. Mem. 1: 609.
---Clavaria obtusissima Peck, 1913. Bull. N.Y. State Mus. 167: 39.
Fruit bodies up to 19 x 17 cm, broadly obovate to generally circular in outline. Stipe up to 10 x 5 cm, often smaller, single, solid, rounded at base to bluntly tapering, smooth to minutely tomentose between particles of substrate, often beset with clusters of small branchlets, white where protected, pale dull ochraceous above, unchanging on bruising or handling; flesh white, soft, moist but not slippery. Major branches 2-4, up to 3 cm thick, ascending to almost horizontal, lobed, channelled or rugulose, pale dull ochraceous ("cream color") when young, darkening in age to deep fleshy tan, often splitting lengthwise under weight of upper parts; branches up to 1.5 cm thick, concolorous with major branches; axils lunate below to narrowly rounded above; internode ratio diminishing abruptly at maturity. Apices digitate, coarse when young, expanding to irregularly pistillariform in age, yellow ochre when young, becoming deep golden ochre in age, finally fading to concolorous with branches. Odor mildly rancid; taste distinctly bitter (teste Coker).
Macrochemical reactions: FSW, FCL, GUA: positive. Tramal hyphae of upper branches 2.5-17 µm diam, hyaline, occasionally clamped, thin-walled, parallel; ampulliform clamps common, scallion-shaped, thick-walled (wall up to 1.5 µm thick), unornamented; gloeoplerous hyphae occasional, as undelimited short lengths of refringent hyphae. Hymenium thickening; basidia 49-55 x 8-11 µm, clavate, clamped; contents homogeneous or with a few scattered, small guttules; sterigmata 4, spindly.
Spores 12.6-15.8 x 4.0-4.3 ttm (E = 3.00-4.00; Em = 3.3; Lm = 13.7 tm), cylindrical to boletoid, smooth in profile, "warm buff" in prints; contents homogeneous or with 1-3 dark inclusions; wall up to 0.3 I,m thick; hilar appendix prominent, almost perpendicular to spore axis; ornamentation none (usually) or a few narrow, obscure longitudinal striae.
The Nova Scotian specimens cited below represent the northernmost record of this rather rare taxon. The type speci
men was gathered in Massachusetts, but I have seen specimens from the Blue Ridge Mountains of North Carolina, and Coker recorded it from Chapel Hill.
Diagnostic characters include (1) smooth spores (or sometimes with a suggestion of striae); (2) yellow to ochraceous coloration; and (3) inflated, pistillariform apices in age. In some Nova Scotian specimens, branches were mostly hollow, but this state was not found in other specimens. The description above is of the taxon as I know it, not just of Nova Scotia material.
Spores of R. obtusissima vary considerably in size. Dimensions taken from spore prints are somewhat longer than those from hymenial squashes, as might be expected. Spore statistics of the type specimen are 12.6-15.4 x 3.8-4.2 jm (E = 3.00-4.00; Em = 3.36; Lm = 13.61 µm). This variability has led me to conclude that Peck's Clavaria obtusissima var. albida (1887. Rep. N.Y. State Mus. 41: 79, non Schaeffer) was synonymous with var. obtusissima. Its spores are slightly shorter (11.2-12.6 x 4.2-4.9 µm; E = 2.28-2.93; Em = 2.57; Lm = 11.47 jm). My present thinking would not allow such variability within a single taxon, however, and I now prefer to keep them separate.
Of the ACAD specimens cited under this name by McAfee and Grund (1982), I have examined two. ACAD 12952 was correctly identified, but ACAD 12950 is R. xanthosperma (q.v.). This may account for the mention of the bruising reaction of the context to brownish grey or violet brown, although the rubescent stipe surface is clearly discernable on the dried fruit body.
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