Cantharellus luteopunctatus (Beeli) Heinem. Bull. Jard. bot. Etat Brux. 28(4): 415. 1958.

Buyck, Bart, W. Henkel, Terry & Hofstetter, Valerie, 2019, Epitypification of the Central African Cantharellusdensifolius and C. luteopunctatus allows for the recognition of two additional species, MycoKeys 49, pp. 49-72 : 49

Cantharellus luteopunctatus (Beeli) Heinem. Bull. Jard. bot. Etat Brux. 28(4): 415. 1958. Figs 4, 5, 6

Basionym.

Lentinus luteopunctatus Beeli, Bull. Soc Roy Bot Belge 60: 160. 1928.

Original diagnosis.

"Pileo carnoso-coriaceo, centro depresso, margine incurvato, luteo; furfuraceo brunneo, 3,5-4 cm. lato; stipite cylindrico-solido, glabro, concolori, 3 × 0,5-0,7 cm, lamellis deccurentibus, luteis; sporis ovoideis 5-6 × 3,5-4 μm, carne lutea."

Holotype.

DEMOCRATIC REPUBLIC OF CONGO. Central forest district, near Djongo-Akula, dispersed on the soil of the dry Gilbertiodendron dewevrei forest, Dec. 1925, Mme. Goossens-Fontana 502 (BR).

Iconography.

HEINEMANN (1958, fig. 47; 1959, pl. XXVI, fig. 6).

Original description.

(freely translated from French) "Pileus rather thick, 49 mm diam., soon depressed, concave with rounded, then straight margin, bright lemon yellow, punctuated - particularly in the center - with minute brownish squamules. Stipe 30 × 6 mm, [30-50 × 5-11 mm], cylindrical, solid inside, yellow, finally rusty, faintly covered from brownish scales. Gills very crowded, deeply decurrent, very narrow, 0.5-11 mm wide (sic!), yellow, irregularly forked, interconnected by rather abundant transversal anastomoses. Context firm, bright yellow, more orangish near the stipe base. Taste strong, bitter. Spore print white. Exsiccatum orangish brown-ochre.

Spores hyaline, shortly ellipsoid, 4.9-6.0 (7.5) × 3.8-4.6 (5) μm, granular inside, thin-walled, not amyloid, with a small apiculus. Basidia narrowly clavate, 30-40 × 6.7-9.5 μm, 4-spored, perhaps sometimes 6-spored. Hymenium not or only slightly accrescent. Subhymenium narrow. Pseudoparenchyma composed of very long and slender elements, mixed with some oleiferous hyphae that do not color in Congo Red. Pileipellis undifferentiated; squamules formed of hyphae united in bundles made up of yellowish to pinkish cells; terminal cells lanceolate or clavate, 6-13 μm diam. Hyphae not amyloid."

Description of the epitype.

Basidiomata scattered to occasionally caespitose. Pileus up to 65(-75) mm diam., initially broadly convex with shallow depression, extending outward and upward with age, becoming increasingly infundibuliform with downturned margin, deep golden yellow (2-3A4), beset with minute, conical erect tufts, these flesh-brown, more concentrated over the disc but extending and gradually more widely dispersed toward margin; intervening surface shiny-glabrous; margin irregularly crenulate, slightly wavy. Hymenophore composed of very thin, crowded, ridge-like gill folds, creamish to nearly concolorous with the pileus surface (2-3A3), occasionally developing tannish overtones with age (3-4A3), decurrent and fairly abruptly demarcated from the sterile stipe surface, discoloring slowly darker yellow to orangish where injured, repeatedly forking, also abundantly cross-connected between stipe and pileus margin at almost right angles, becoming increasingly tortuous and anastomosed with advanced age; edges even and concolorous. Stipe subequal or slightly tapering toward the base, (17 –)24– 43 × 4 –8(– 10) mm, concolorous with pileus, beset apically with conical, flesh-brown, erect tufts, longitudinally striate below; extreme base often developing some white mycelial tissue at the soil interface. Context solid, yellow, unchanging to increasingly yellow. Odor mildly chanterelle-like. Taste mild, nutty, pleasant, somewhat tardily acrid in young specimens. Spore print not obtained.

Basidiospores short-ellipsoid to ellipsoid, (5.4 –)5.7–6.04–6.4(– 7.1) × (3.9 –)4.0–4.29–4.6(– 5.0) µm, Q = (1.24)1.29 –1.41–1.53(– 1.79), smooth. Basidia quite short, mostly 30 –40(– 50) × 6-7 µm, (5-)6-spored. Cystidia none. Subhymenium cells mostly hardly wider than the basidium base, but locally more inflated parts make it somewhat intermediate between distinctly pseudoparenchymatous and filamentous. Pileipellis composed periclinal thin-walled hyphae of variable diameter, but most ca. 10 µm wide, that locally emit anticlinal tufts of short-septate chains of more or less inflated cells, with the largest cells in these chains distinctly zebroid incrusted and the more terminal cells distinctly thick-walled (up to 1 µm thick); terminal cells 30-60 µm long, mostly (6 –)10– 15 µm wide, subcylindric or clavulate to lageniform, with obtusely rounded to attenuated tips, never remarkably undulate or irregular in outline. Clamp connections absent.

CAMEROON. East Region: Dja Biosphere Reserve, Northwest Sector near the village of Somalomo, Upper Dja River Basin, within 2 km radius of Dja base camp located at 3°21'29.8"N, 12°43'46.9"E, 650 m a.s.l., 2 km SW of Dja base camp, under Gilbertiodendron dewevrei , coll. T. Henkel, 22 Nov 2016, TH 10285 (YA, epitypus hic designatus, duplicates at HSC G1264 and PC). MycoBank MBT 384670.

Additional specimens examined.

CAMEROON. East Region: Dja Biosphere Reserve, Northwest Sector near the village of Somalomo, Upper Dja River Basin, 1.4 km SW of Dja base camp, under G. dewevrei , coll. T. Henkel, 2 Sep 2014, TH 9921 (YA, HSC G1265, PC); 2 km SW of Dja base camp, under G. dewevrei , coll. T. Henkel, 29 Aug 2017, TH 10442 (YA, HSC G1266, PC).

Discussion.

Cantharellus luteopunctatus has long been considered as "uncomfortably close" to C. densifolius . Eyssartier (2001) found no significant microscopic differences between their holotypes, and suggested that C. luteopunctatus was likely a more yellowish color form of the latter species. For several decades following its original description C. luteopunctatus was not discussed in the literature, until recently by Eyi N’dong et al. (2011) who accepted it as an independent species. Both C. luteopunctatus and C. densifolius were also maintained as independent entities in a recent identification key to all African chanterelles ( De Kesel et al. 2016). Our choice of epitype has been based on the specimen with the highest degree of similarity with the original macro- and microscopic description of C. luteopunctatus , and the original watercolor showing a species with a similar stature, color, and laterally compressed stipe (Fig. 4c).

Close reading reveals some differences between the original descriptions for C. luteopunctatus and C. densifolius . Apart from the difference in pileus color, the second most important difference, also noted by Eyi N’dong et al. (2011), concerns the configuration of the hymenophore. Gill folds were originally described for C. luteopunctatus as "irregularly forking and with many interstitial anastomosing veins", versus those of C. densifolius which were “1– 4 times forking, not interveined" ( Heinemann 1958). Although the presence and frequency of anastomoses between gill folds can be highly variable among and within Cantharellus species, it remains nevertheless a very informative feature to characterize those species that appear always to be on one side of the continuum ( De Kesel et al. 2016). In this particular case, the macromorphologies of recent collections suggest that this feature is consistent across, and different between, specimens of C. luteopunctatus and C. densifolius .

Our collections also demonstrate a difference in hymenophore color between the species, something that is not evident from Heinemann’s descriptions. Heinemann described C. luteopunctatus as having a yellow hymenophore, but does not indicate the color for the hymenophore of C. densifolius , although the original watercolor clearly shows it to be more or less ochraceous (see Fig. 2c here, and Heinemann 1959, Plate XXVI, fig. 6). Our collections confirm this ochraceous to dirty isabelline color of the hymenophore of C. densifolius , even when still relatively young, whereas the hymenophore color is more variable in C. luteopunctatus due to the translucent context above. The hymenophore of C. luteopunctatus is pure white when young, but it may also have pinkish tinges when the pileus surface is still densely covered by pinkish brown squamae, and then becomes more yellowish (which is the color mentioned in the original description) with maturation due to the yellowing context and absence of squamae over the expanded pileus margin. As in C. densifolius , the yellowing can be of variable intensity; for instance, the exposed context of TH 10442 is more strongly chrome yellow than that of the epitype (Fig. 5a).

Other considerable differences between C. luteopunctatus and C. densifolius include the surface structures of the pileus and stipe. In C. luteopunctatus , distinct central pileal squamae are erect, flesh brown to pinkish brown, and strongly separated and paler toward the margin. The pinkish color of the squamae was also mentioned in the original description of Heinemann (1958). In contrast, the pileus surface of C. densifolius is a continuous tomentum that lacks a pinkish flesh color and is woolly-fibrous, before breaking up concentrically in appressed fragments. Furthermore, in C. luteopunctatus the upper stipe surface has the same squamae as the pileus center, whereas in C. densifolius the stipe surface is smooth (compare Figs 2, 4, 5).

Micromorphologically, the basidiospores are nearly identical in both species (Table 1), but the pileipellis differs dramatically. In C. luteopunctatus the pileipellis is composed of fascicles of thin- to slightly thick-walled hyphae (corresponding to the erect squamae) that are recognizable on the background of more or less parallel, thin-walled hyphae of the interstitial surface, whereas in C. densifolius , the thicker-walled hyphae are not organized in fascicles. Moreover, in the latter species the distal cells of these thick-walled hyphae are much more undulate-sinuous in outline and narrower than those of C. luteopunctatus .

A final remark concerns the edibility of these Central African chanterelles: In Cameroon C. luteopunctatus basidiomata are mild-flavored and consumed by the indigenous Baka, while C. densifolius slowly develops a very strong bitterness and is not consumed by the Baka (T. Henkel, pers. obs.). While the bitter taste was also noted in the original description ( Heinemann 1958), the first author did not detect bitterness for C. densifolius specimens from the Central African Republic.