Cystidia, Hubner, 1819

Rossi, Walter, Das, Kanad, Hembrom, Manoj Emanuel, Santamaria, Sergi, Parihar, Arvind, Ghosh, Aniket, Henkel, Terry W., Hofstetter, Valerie & Randrianjohany, Émile, 2020, Fungal Biodiversity Profiles 91 - 100, Cryptogamie, Mycologie 20 (4), pp. 69-107 : 74-78

94. Cantharellus albidosquamosus Buyck, T.W. Henkel & V. Hofst. , sp. nov.

( Figs 4-6)

Differs from other African chanterelles with crowded gill folds by the combination of a white to pale yellow pileus, covered with suberect, dark brown squamulae, the absence of abundant anastomoses in between gill folds, the less intense yellowing of its context or surface upon injuries, and its association with Uapaca trees in the Central African rain forest.

HOLOTYPE. — Cameroon. Eastern region, Haut-Nyong division, Somalomo subdivision, Dja Biosphere Reserve, in Gilbertiodendron rain forest, growing under Uapaca sp. , 2.IX.2014, T. Henkel TH 10005 (holotype YA; isotypes PC[PC0713875], HSC G1291).

MYCOBANK. — MB 834838.

ADDITIONAL EXAMINED MATERIAL. — Cameroon. Eastern region, Haut-Nyong division, Somalomo subdivision, Dja Biosphere Reserve, W of Dja base camp, c. 650 m alt., in Gilbertiodendron rain forest, 28.XI.2016, gregarious in group of six on one square meter at the basis of Uapaca, TH 10314 (PC[PC0142511]); ibid., 400 m N of base camp in mixed forest, under Uapaca acuminata , 10.XII.2016, TH10375 (PC[PC0142517]); ibid., c. 5 km SW of base camp in Gilbertiodendron stand 4; under G. dewevrei , 20.IX.2018, TH10705 (TH 10314 (YA, PC[PC0142511], HSC G1292) TH 10375 (YA, PC[PC0142517], HSC G1293) TH 10705 (YA, PC[PC0142531], HSC G1294).

ETYMOLOGY. — Named after the whitish to very pale yellowish pileus combined with the (often strongly) squamulose aspect of its surface in the pileus center.

gene (200 bootstrap replicates with conflict assumed when two different relationships, one being monophyletic and the other being non-monophyletic, for the same set of taxa were both supported with significant bootstrap values equal or greater than 70%; Mason-Gamer & Kellog 1996). Searches for the most likely tree included three independent runs.The holotype of our new species is indicated in bold. Branches that received significant bootstrap (BS) support (equal or greater than 70%) based on 500 BS replicates are in bold and BS values indicated along the branches. Newly produced sequences are shown in bold in the Table 1.

Rossi W. et al.

DESCRIPTION

Pileus

With downturned, inrolled margin and depressed center when young, then deeply infundibuliform with plane to uplifted and irregularly lobed or wavy margin, 29-46 mm diam., up to 23 mm high, the surface light tannish cream in the center (3-4A3), but topped with flesh brown to reddish brown, minute, fibrillose, erect squamules getting gradually lower, smaller and more and more dispersed toward the pileus margin.

Hymenophore

Decurrent, composed of well-developed, thin and crowded gill folds, these abruptly delimited from sterile stipe surface, repeatedly forking, pale orange-cream (3A2-3), unchanging, easily rubbed off and rather delicate, slightly interveined near the extreme margin; edges smooth.

Stipe

Subcylindrical, 15-18 × 5-7 mm, up to 9 mm wide at apex, concolorous with hymenophore, developing whitish tomentum at the extreme base.

Context

White to pale cream, thin (c. 1 mm) in pileus ad mid-radius, very slowly yellowing, very distinctly so in the lower stipe, but not turning ferruginous.

Taste

Mild.

Odor

Typical, of apricots, not strong.

Spores

Spore print not obtained. Shortly ellipsoid, (5.63)6.0-6.42- 6.9(7.5) × (3.9)4.2-4.64-5.0(5.2) µm, Q = (1.2)1.3-1.39- 1.5(1.6), smooth.

Basidia

Rather short, 35-50 × 6-7 µm, mostly 4-5(-6) spored. Subhymenium strongly pseudoparenchymatic, of large, inflated cells up to 4-5 septa down.

Cystidia

None.

Pileipellis

With hyphal terminations composed of chains of regularly subcylindrical cells, not particularly sinuous nor undulate in outline, 5-10 µm diam., distinctly thick-walled; the terminal cell frequently narrowed at the apex or subapically slightly constricted, not shorter compared to subapical cells, usually 50-100 µm long.

NOTES

Because of the crowded gill folds, our new species is strongly reminiscent of C. densifolius Heinem. for which it was undoubtedly mistaken in the past, even more as both are very similar under the microscope (see Buyck et al. 2019). The epitypification of C. densifolius by Buyck et al. (2019) has demonstrated that crowded gills are shared by several, more or less similar species in C. subg. Rubrini sect. isabellini Eyssart. & Buyck.Whereas our new species differs from C. densifolius and the recently described C. tomentosoides Buyck & V. Hofst. in the general coloration of the various parts of the fruiting body, it is more similar in the field to Malagasy C. brunneopallidus Buyck, Randrianjohany & V. Hofst. and C. griseotinctus Buyck, Randrianjohany & V. Hofst. (in Hyde et al. 2019), although the latter has more widely spaced gill folds. Our multigene phylogenetic analysis indeed places C. albidosquamosus Buyck, T. W. Henkel & V. Hofst. , sp. nov. sister to the Malagasy C. brunneopallidus which is not a close relative to C. densifolius . Whereas C. brunneopallidus was so far only found under Intsia trees ( Caesalpiniaceae ) on Madagascar’s east coast, our new chanterelle seems to have an equally specific habitat as nearly all collections were found under Uapaca trees (Phyllantaceae) in the Gilbertiodendron - dominated rain forest.

The various collections made for C. albidosquamosus Buyck, T.W. Henkel & V. Hofst. , sp. nov. show that the strongest impact on its field habit is caused by the intensity of overall yellowing, some specimens becoming entirely pale yellow at maturity. In the latter case, our species is easily distinguished from the equally yellow and squamulose C. luteopunctatus Heinem. because the crowded gill folds of the latter species have abundant transversal anastomoses between individual gill folds, whereas these are completely lacking in our new species.