Lactarius hatsudake

Lactarius hatsudake Tanaka, Bot. Mag.

Index fungorum number 223913

Pileus 30–100 mm diam., at first convex with an incurved margin, sometimes with a papilla, then expanded and margin bent downwards to slightly incurved, finally widely infundibuliform; margin sometimes slightly translucently striate; surface smooth, greasy to slightly viscid when wet, zonate, especially near the margin; colour pale reddish buff to dirty brownish pink or with ochraceous tinges (7/8B3/4), sometimes with a darker centre (8C5), zones dull red, older or discoloured specimens very light orange or with a greenish ochraceous centre, discolouring bluish green in age (25F6), slightly hygrophanous. Lamellae decurrent, rather crowded to subdistant, often branched, rather broad, colour dull, pale reddish when young, vinaceous red when mature, becoming more ochraceous, mixed with greenish or bluish green in age; edge entire, paler. Stipe 15–40 × 6–20 mm, short, tapering downwards, becoming hollow, glabrous, colour dull reddish (9C/D5), often covered with a white layer, without scrobicules, with a white zone at the apex. Context firm in the centre of the pileus to very thin at the margin, white to buff, staining vinaceous red (10/11C5) underneath the pileipellis or on the entire pileus surface and underneath the stipitipellis, later becoming greenish; smell indistinct to sweet, agreeable; taste mild. Latex scarce, vinaceous red (11D6/7), unchanging. Spore deposit unknown. Spores 7.7–8.3–9–9.7 × 5.6–6.2–6.6–7.5 μm, broadly ellipsoid to ellipsoid (n = 180, Q = 1.21–1.30–1.39–1.54); ornamentation up to 0.8 (1) μm high, composed of conspicuous, large, but rather faint amyloid spots connected with mainly thick ridges but also with scarcer thin ridges, forming an irregular, dense and almost complete network, some isolated warts present; plage often with an irregular, faintly amyloid pattern or distally amyloid. Basidia 40–52 ×8–14 μm, subclavate, 4-spored; sterigmata 4.5–8 μm long. Pleuromacrocystidia very scarce but more abundant close to the lamella edge, 42–48 × 7–9 μm, emergent, subfusiform, with a moniliform or acute apex, thin-walled. Pseudocystidia abundant, 2.5–5 μm diam., not to slightly emergent, cylindrical to tortuous, with an ochre-yellow content. Lamellar edge sterile with scarce cheilomacrocystidia but macrocystidia mostly abundant close to the edge; cheiloleptocystidia mostly 8–16 × 3.5–6 μm but rarely very conspicuous and emergent, up to 35–40 μm long, subclavate to cylindrical or more irregular, hyaline, thin-walled; cheilomacrocystidia 24–35 × 4.5–6 μm, subfusiform with a moniliform apex, content needle-shaped or granular, thinwalled. Pileipellis an ixocutis, 50–300 μm thick, of mainly shriveled and gelatinised hyphae in the top layer, deformed and swollen hyphae also present; hyphae 1–6 μm broad, thin-walled. Stipitipellis a cutis, 30–70 μm thick, of thin-walled, strongly interwoven hyphae 2–6 μm broad; no shriveled or gelatinised hyphae. Clamp connections absent.

Habitat: Under Pinus kesiya.

Distribution: Recorded from China, Japan, the Bonin Islands, eastern Russia, Korea, Thailand and Taiwan. Under Pinus spp. such as P. thunbergii, P. densiflora, P. liuchuensis, P. yunnanensis, P. kesiya; in Japan in lowland forests and gardens etc., abundant in (early) autumn; in Yunnan (Southwest China) throughout the mushroom season (May to September) (Tanaka, 1890; Nagasawa, 1998; X.H. Wang, pers. comm.).

Material examined: JAPAN, Kagoshima, Aira-gun, Makizono-cho, Oonami-yama, 1060–1300 m alt., under Pinus densifolia, in mixed coniferous and hardwood forest, 27October 2000, leg. E. Nagasawa & T. Fujita, TMI 24414 (TMI) – THAILAND, Chiang Mai Prov., Mae Teng Distr., Tung Joaw village, forest trail, 1300 m alt., N19°08.07' E98°38.90', secondary forest, under Pinus kesiya, on a steep wall of red soil along the trail, 20 June 2004, leg. R. Walleyn & A. Verbeken 2004-014 (GENT), leg. Huyen T. Le 110 (CMU, SFSU) – ibid., secondary forest with Pinus kesiya, Castanopsis etc., 30 June 2004, leg. R. Walleyn & A.Verbeken 2004-159 (GENT), leg. Huyen T. Le 167 (CMU, SFSU) – ibid., secondary forest with Pinus kesiya, Castanopsis etc., 07 August 2004, Huyen T. Le 215 (CMU, SFSU) – ibid., secondary forest with Pinus kesiya, Castanopsis etc.,. 16.07.2005, Huyen T. Le 354 (CMU, GENT, SFSU) – ibid., secondary forest with Pinus kesiya, Castanopsis etc., 03 August 2005, Huyen T. Le 367 (CMU, GENT, SFSU) – Chiang Mai Prov., Mae Teng Distr., Huai Nam Dang National Park, nature trail, 1530 m alt., N19°18.29' E98°35.88', forest with Pinus kesiya, Bamboo, scattered Castanopsis, 28 June 2004, leg. R. Walleyn & A. Verbeken 2004-134 (GENT), leg. Huyen T. Le 158 (CMU, SFSU) – ibid., forest with Pinus kesiya, Bamboo, scattered Castanopsis, 28 June 2004, leg. R. Walleyn & A. Verbeken 2004-138 (GENT), leg. Huyen T. Le 159 (CMU, SFSU) – ibid., forest with Pinus kesiya, Bamboo, scattered Castanopsis, 28 June 2004, leg. R. Walleyn & A. Verbeken 2004-139 (GENT), leg. Huyen T. Le 160 (CMU, SFSU) – ibid., forest with Pinus kesiya, Dipterocarpus sp., Bamboo & scattered Castanopsis, 29 June 2005, Huyen T. Le 331 (CMU, GENT, SFSU) – Chiang Mai Prov., Mae Teng Distr., Ban Pha Deng village, Pathummikaram Temple, forest trail, 1050 m alt., N19°06.28,8 E98°44.47,3″', solitary to gregarious on the soil and leaves, near the trail, rain forest dominated by Castanopsis armata, Dipterocarpus sp., Pinus kesiya, 12 June 2006, leg. Roy Halling and Huyen T. Le, Huyen T. Le 428 (CMU, GENT, SFSU).

Notes: Lactarius hatsudake is one of the highly prized edible mushrooms in Japan and large parts of China and probably also in Korea and eastern Russia (Nagasawa, 1998; Wang et al., 2004, Nuytinck et al., 2006). It is not known as an edible species in Thailand. Lactarius hatsudake is characterised by its wine-red latex and its association with Pinus spp. The size of the basidiocarps is quite variable, e.g., very small to rather large basidiocarps are often encountered together (X.H. Wang, pers. comm.). Microscopically the heavy spore ornamentation with the large but faintly amyloid spots is typical and a reliable feature for identification. Molecular evidence shows that the genetic variability in L. hatsudake is high, which might indicate that our species concept is relatively broad here (Nuytinck, 2005). Moreover, this molecular variability is also confirmed by morphological diversity. The collections from Thailand showed a striking hygrophanous colour change of the cap that is not reported for the Chinese collections. It is possible that at least several varieties can be distinguished within L. hatsudake but more observations on fresh material are needed. The description above is based entirely on Thai material.

Fig. 1 Lactarius hatsudake. a. Basidiocarp. b. Spores. c. Basidia. d. Pleuromacrocystidia. e. Marginal cells. Scale bars = 10 mm (basidiocarp) and 10 μm.