Differs from its closest Asian and North American relatives in the variously coloured but often bright lemon yellow pileus, similarly tinted stipe and smaller size, as well as in differences in sequence data produced for the transcription elongation factor (tef-1).

Figure 3. 

Cantharellus citrinus (holotype) a spores b basidia and basidiola c hyphal extremities of the pileipellis near mid-radius. Scale bar: 10 μm, but only 5 μm for spores. Drawings B. Buyck.

Figure 4. 

a–c Cantharellus citrinus, yellow, more common form a (VA 13.170) b C. citrinus, reddish orange form (VA 16.169) c (VA 13.156, holotype). Photos V. Antonín.

South Korea. Geoi-san, Cheong-cheon-myeon, alt. 330 m, 36°37'02.99"N, 127°49'36.56"E, 14 Aug 2013, V. Antonín, R. Ryoo & K.-H. Ka, 1691 / VA 13.156 (holotype: BRNM 825748; isotype: PC 0142457).

Basidiomata dispersed in small groups or fascicles. Pileus 4–20 mm broad, convex, with involute margin when young, then plane or infundibuliform with depressed centre and inflexed to straight, smooth margin, irregularly undulate when old, hygrophanous, finely tomentose when very young, soon glabrescent and smooth or slightly rugulose, uniformly coloured, light yellow, orange yellow to light orange (3–4A6, 4–5A5–7), sometimes with greyish yellow tinge when old. Hymenophore composed of thick vein-like folds, sometimes strongly decurrent in a reticulate pattern on upper stipe, often not reaching the pileus margin, forking or with rare lamellulae, transversely anastomosed in between, white to whitish (3A2); edges concolorous. Stipe 4–22 × 1–3(–4) mm, slightly tapering towards base when young, then cylindrical, sometimes curved, finely pubescent when young, later glabrescent, smooth, concolorous with pileus or slightly paler. Context thin, yellowish, fibrillose-hollow and yellowish whitish in stipe when old, with a spicy apricot smell and mild taste. Spore print not obtained.

Basidiospores ellipsoid, (7.3–)7.6–8.24–8.4(–8.8) × (5.1–)5.4–5.67–5.9(–6.1) μm, Q = (1.32–)1.34–1.42–1.50(–1.56), smooth, thin-walled. Basidia mostly (42–)66–80 × 8 μm, 4–5(–6)-spored, narrowly clavate; basidiola subcylindrical and slender when young, undulate-wavy in outline, later becoming narrowly clavate, subfusoid, sometimes irregular, rarely submoniliform, thin-walled. Cystidia not observed. Subhymenium composed of narrow, filamentous and cylindrical cells. Pileipellis a cutis composed of cylindrical, ± thin-walled, smooth or minutely incrusted, sparsely septate, (4–)8–12 μm wide hyphae; terminal cells (36–)50–110 × 4.0–15 μm, appressed to suberect, mostly slightly clavate, some with a subapical weak constriction, obtuse, thin-walled. Stipitipellis a cutis of cylindrical, slightly thick-walled, 2.5–6.0(–7.0) μm wide hyphae with isolated terminal cells distinct only in a narrow zone at very top, otherwise rare to absent, 20–51 × 4.0–11 μm, (narrowly) clavate, cylindrical or subfusoid, thin-walled. Clamp connections everywhere and distinct.

On soil near Quercus mongolica Fisch. ex Ledeb., Q. acutissima Carruth., Quercus sp., Castanea crenata Siebold & Zucc., Carpinus laxiflora (Siebold & Zucc.) Blume and Abies koreana E.H. Wilson.

The name refers to the frequent bright lemon yellow colour of pileus and stipe surface of the most common form.

Jinan, Jeongcheon-myeon, Unjangsan Recreational Forest, alt. 390 m, 35°54'01.13"N, 127°24'59.41"E, 7 Sep 2016, V. Antonín, R. Ryoo, K.-H. Wang & Y.-S. Jang, 1710 / VA 16.169 (BRNM 825753, PC 0142467). Ibid., 1711 / VA 16.170 (BRNM 825754, PC 0142468). Yeongdong, Yonghwa-myeon, Minjoojisan Recreational Forest, alt. 540 m, 36°03'14.57"N, 127°49'43.15"E, 26 Aug 2015, V. Antonín, K.-H. Ka, K.S. Kim & J.A. Kang, 1715 / VA 15.93 (PC 0142472).

The description is based on the type specimen, but examination of the other specimens shows that variation of morphological features includes a rather wide amplitude of the overall colour, which seems – based on identical tef1 sequences – to extend from entirely and predominantly pale lemon yellow to an overall deep orange. Collection from Jinan (VA 16.169, BRNM 825753, PC 0142467) differs from other collections of this species by an orange (5–6A7) pileus, light yellow to light orange (4–5A5) lamellae and a stipe more or less concolorous with the pileus.

This new species is here placed in Cantharellus subg. Cinnabarini (Fig. 2), a subgenus that comprises several species exhibiting a similarly wide colour range, e.g. the Malagasy C. variabilicolor Buyck & V. Hofst. (in Ariyawansa et al. 2015) or the North American C. cinnabarinus (Schwein.) Schwein. Cantharellus citrinus is here shown to be part of a well-supported clade composed of two other Asian species, the Chinese C. phloginus and Korean C. albovenosus. The latter two species are very different in general aspect, but, except for a single mutation in the coding part, the tef-1 sequences of both species are identical, even including the introns. Yet, their very different general habitus justifies us in our view that we should accept them as a separate species. The clade comprising these Asian species is sister to a clade composed of North American species.

Because of its very small overall size and comparable overall colour, C. citrinus could also easily be mistaken for some species in Cantharellus subg. Parvocantharellus Eyssart. & Buyck, in particular the European C. romagnesianus (= C. pseudominimus Eyssart. & Buyck, see Olariaga et al. 2015). Under the microscope, C. citrinus differs hardly from its Asian relatives and identification relies principally on field characters or sequence data.

Differs from the European C. romagnesianus in the distinctly smaller spores and shorter basidia (see Olariaga et al. 2016), the strongly veined hymenophore and sequence data obtained from the transcription elongation factor one alpha (tef-1).

Figure 5. 

Cantharellus curvatus (VA 14.57, holotype). Scale bar: 15 mm. Photos V. Antonín.

South Korea. Yesan, Deoksan-myeon, Sudeok-sa, alt. 220 m, 36°39'57.40"N, 126°37'20.91"E, 8 Jul 2014, V. Antonín & K.-H. Ka, 1695 / VA 14.57 (holotype: BRNM 825749; isotype: PC0142461)

Basidiomata in groups. Pileus 20–30 mm broad, low convex with a low broad central umbo and involute margin, then irregularly applanate or shallowly infundibuliform with an undulate, often uplifted margin, hygrophanous, not translucently striate, smooth, glabrous, watery dull yellow when moist, drying out to orangish yellow (± slightly more yellow than 4A5). Hymenophore composed of distant gill folds [L = 37–40], shortly decurrent, thick, sometimes furcate when young, furcate-anastomosed in upper half when old, pale yellow (± 3A3), ± dirty (greyish) yellow at the end; edge concolorous. Stipe 25–30 × 3.5–4 mm, cylindrical and tapering towards base, longitudinally fibrillose, yellow (± concolorous with pileus). Context pale whitish-yellowish, with cantharelloid smell.

Basidiospores (7.25–)7.5–8.05–9.0 × 5.0–5.25–6.0(–6.25) μm, Q =1.40–1.52–1.66, ellipsoid, rarely broadly ellipsoid, ventrical applanate or suballantoid, thin-walled, smooth. Basidia 42–55 × 9.5–12 μm, (4–)6-spored, narrowly clavate, clamped. Basidiola 15–42 × 3.0–11 μm, clavate, cylindrical, subfusoid, irregularly curved or undulate. Trama hyphae of cylindrical to fusoid, clamped, ± thin-walled, 4.0–20 μm wide cells. Pileipellis a cutis composed of cylindrical, clamped, mostly thin-walled, 4.0–10 μm wide hyphae; terminal cells appressed to suberect, mostly cylindrical, slightly thick-walled, up to 80 μm long and 5.0–10(–15) μm wide. Stipitipellis a cutis of cylindrical, parallel, slightly thick-walled, clamped, 3.0–6.0 μm wide hyphae. Terminal cells appressed to suberect, clavate or cylindrical.

On soil under Pinus densiflora Siebold & Zucc. and Castanea crenata.

Referring to the curved-undulate hymenial cells, viz. basidia and particularly basidiola.

This Asian species differs from the European C. romagnesianus, presently the most similar chanterelle, in the distinctly smaller spores and shorter basidia (see Olariaga et al. 2016), further also in the strongly anastomosing hymenophore and in sequence data obtained from the transcription elongation factor one alpha (tef-1).

Figure 6. 

Cantharellus curvatus (holotype) a spores b basidia and basidiola c hyphal extremities of the pileipellis near mid-radius. Scale bar: 10 μm, but only 5 μm for spores. Drawings B. Buyck.

Pileus 10–40 mm broad, convex-conical when young, soon plane to broadly funnel-shaped, sometimes with a low obtuse umbo at centre, margin involute then inflexed to straight and undulate, pruinose when young then ± glabrous, greasy when moist, smooth or slightly uneven, not translucently striate, yellow (4A7–8), sometimes with darker (“dirty”) centre. Lamellae moderately close, L = c. 25–30, decurrent, often furcate, rarely branched, whitish to pale cream from ± half radius toward the stipe attachment, then yellow towards pileus margin. Stipe 20–40 × 3.5–6 mm, cylindrical, not broadened towards base, finely pruinose when young, then glabrous, white, not hollowing. Context yellow beneath pileipellis, white otherwise. Smell slight, cantharelloid. Taste mild with slightly sharp aftertaste. Spore print not obtained.

Figure 7. 

Cantharellus anzutake, microscopic features. Hyphal extremities at the pileus surface, on the left near the pileus center, on the right closer to the pileus margin. Scale bar: 10 μm. Drawings B. Buyck.

Basidiospores ellipsoid to ovoid, (6.9–)7.2–7.56–8.0(–8.3) × (4.6–)4.8–5.10–5.4(–5.6) µm, Q = (1.31–)1.39–1.49–1.58(–1.68), smooth, with a small apiculus. Basidia clavate-pedicellate, (60–)70–80 × 7–8 µm, long and slender, mostly 6(–5)-spored with stout sterigmata. Subhymenium filamentous, composed of long and slender, cylindrical cells of similar diam. as the basidium base. Cystidia none. Pileipellis a loose tissue of intricately intertwining, sparsely septate, long and slender hyphal ends, near the pileus margin often aggregated in long tufts; hyphal ends composed of long, cylindrical, 5–8(–12) µm diam. cells, with refringent, thin- to slightly thickened walls, but in the pileus centre more frequently thick-walled; the terminal cell slender, toward the pileus margin (40–)60–130 µm long, obtuse rounded at the tip, cylindrical, hardly differentiated from subapical ones; in the pileus centre often somewhat irregularly constricted near the tip, but never very strongly so, and usually shorter, 30–100 µm, and on average somewhat narrower.

Figure 8. 

Cantharellus anzutake. Microscopic features. Basidia, basidiola and spores. Scale bar: 10 μm, but only 5 μm for spores. Drawings B. Buyck.

On soil under Pinus densiflora, Carpinus laxiflora and Quercus mongolica.

Jinan, Jeongcheon-myeon, Unjangsan Recreational Forest, 35°54'05.55"N, 127°24'53.89"E, alt. 400 m, 31 Aug 2016, V. Antonín, K.-H. Ka & S.-H. Kim, 1708 / VA 16.140 (BRNM 825751, PC 0142465). Ibid., VA 16.142 (BRNM 825752, PC 0142466).

Figure 9. 

Cantharellus anzutake a, b Ka & Ryoo 3_Korea_1-2 [22/08/2012, Pyeongchang, Jungwangsan, 37°27'27.48"N, 128°29'04.35"E, 771 m asl, under Pinus koraiensis Siebold & Zucc.] c Antonín 16.140 (PC0142465). Note the very pale hymenophore in young specimens, remaining for a long time paler closer to the stipe when maturing. Scale bar: 20 mm.

This species is a typical member of Cantharellus subg. Cantharellus, and belongs to a group that is often referred to as the ‘golden chanterelles’ or the C. cibarius Fr. complex, representing the commercially most important chanterelles on the international market. This species complex is reputedly very difficult to identify, in particular because of the very variable field aspect of the various species involved (Olariaga et al. 2015, 2016). Hence, positive identification frequently requires molecular sequence data. Our identification is here based on the high quality ITS sequence we obtained for VA 16.142 and which is identical to the one deposited for the C. anzutake holotype (GenBank LC085359, similarity 100% for 100% coverage); both these ITS differ from other yellow species of chanterelles described from Asia by a ca 100 bp deletion in the ITS1 region (Ogawa et al. 2018).

Because of the whitish hymenophore when young and the sometimes deep orange-yellow to cinnamon buff pileus surface, this species may be somewhat reminiscent of C. albovenosus. The latter species, however, has always a much brighter orange pileus and a more veined hymenophore that remains white, even with age, and it belongs in subgenus Cinnabarini (see Antonín et al. 2017). It is interesting to note that both Japanese and Korean specimens were collected near Pinus densiflora among possible host trees.