Lactarius vividus X.H. Wang, Nuytinck & Verbeken, 2015

Wang, Xiang-Hua, Nuytinck, Jorinde & Verbeken, Annemieke, 2015, Lactarius vividus sp. nov. (Russulaceae, Russulales), a widely distributed edible mushroom in central and southern China, Phytotaxa 231 (1), pp. 63-72 : 67-70

Lactarius vividus X.H. Wang, Nuytinck & Verbeken , sp. nov. Fig. 3a–f , Fig. 4

Mycobank: MB 812841

Diagnosis:— Lactarius vividus differs from the other orange-colored species of Lactarius sect. Deliciosi by the subdistant to distant lamellae and heavy basidiospore ornamentation.

Holotypus:— CHINA. Hubei Province, Yingshan, Taohuachong Forest Park, N30°58'29.37'' E116°02'00.68'', elev. 960 m, under Pinus taiwanensis , 30 Aug. 2011, X.H. Wang 3039 (KUN-HKAS 73582!).

Etymology:—Named after the vividly colored lamellae.

Pileus 3–10 cm in diam., involute when young, soon plano-applanate with slightly depressed center or even reflexed; surface faintly zonate, with only 1/2–2/5 of the margin with clear or faint concentrical zones or azonate, hygrophanous, subgreasy, light yellow (4A5–5A5), orange (5A6), greyish orange (5B5), golden yellow (5B7), brownish yellow (5C7), ochraceous yellow mixed with grayish-green tinge in the center and orange (6B6) at the margin when old, orange mixed with bluish-green tinge when dry, locally with dull greenish patches; margin sulcate when fully mature in some basidiocarps, occasionally locally lobate. Pileus context 2–8 mm thick, pale orange (5A3, 5A4) or paler than the pileus, not discoloring when bruised, with pale greenish tinge when old. Lamellae 2–8 mm wide, thick, subcrowded initially, becoming subdistant to distant with age, adnate to shortly decurrent, light orange (5A4, 5A5), golden yellow (5B7), orange (6A6, 6A7, 6A6–6B6), unchanging or discoloring dull green (28E3) to green when old or bruised. Stipe 3–4.5 × 0.8–2 cm, equal or slightly tapering downwards; surface subhygrophanous, rarely scrobiculate, light orange (6A5, 5A5–6A5) to golden yellow (5B7), almost concolourous with the lamellae, locally paler, with a narrow whitish or paler zone at the apex, rarely with a concolorous apex, discoloring greenish where bruised; base with short, strigose, pale orange or pale greenish hairs. Latex scant, orange (5A6) to golden yellow (5B7), slowly discoloring dull blood-red in 2–10 minutes or when dry. Spore print pale ochraceous.

Basidiospores (5.5–) 7.0–10.0 (–11.0) × (5.0–) 5.5–7.0 (7.5) μm [Q = (1.15–) 1.22–1.46 (–1.55), Q = 1.34 ± 0.07] (320/16/11), ellipsoid; ornamentation up to 1.3 μm high, mostly 0.5–1.0 μm high, composed of ridges and irregular warts forming a broken to almost complete reticulum; plage not amyloid or slightly distally amyloid. Basidia 35–65 × 8–11 μm, subclavate to subcylindrical, 4-spored; sterigmata 5–8 μm long. Pleuromacrocystidia very rare to absent in some collections, rarely common, 35–100 × 7–10 μm, embedded in hymenium or projecting to 30 μm beyond hymenium, subfusiform, sublanceolate, sometimes with a moniliform apex, with a dense granular or massy content. Pseudocystidia abundant, (3–) 5–10 (–12) μm diam., emergent and broadened at apex, sometimes narrowing again at the very end, subcylindrical, rarely forking or branching, with a dense golden-brown to ochre-brown content. Lamellar edge sterile. Cheilomacrocystidia scarce to common, absent in some collections, 20–50 × 3–9 (–10) μm, subcylindrical, subfusiform or sublanceolate, sometimes with a moniliform apex, with a needle-like or granular content. Hymenophoral trama with sphaerocytes and abundant lactifers, lacking rosettes. Pileipellis an ixocutis, 40–150 μm thick, of compact thin-walled hyphae 2–6 μm diam., cylindrical with a round apex, strongly shrivelled and gelatinized, thin-walled, hyaline, parallel with the pileal surface, locally interwoven into an atypical ixolattice; slime layer very thin. Stipitipellis a cutis, rarely an ixocutis, very thin, of slightly gelatinized and shrivelled hyphae 2–5 μm diam. Trama of pileus and stipe with abundant golden-brown to ochre-brown lactifers and rosettes. Clamp connections absent.

Specimens Examined: CHINA. Anhui, Qianshan, Tianzhu Mt. , near Foguang Temple , elev. 630 m, N30°43'17.73'' E116°27'18.31'', under Pinus taiwanensis , 29 August 2011, X. H. Wang 3033 ( KUN-HKAS 73576 ) ; Chongqing, Nanchuan, Sanquan, Jinfo Mt. , elev. 750 m, N29°07'19.20'' E107°11'59.45'', under P. massoniana , 29 July 2010, X. H. Wang 2428 ( KUN-HKAS 61742 ) ; Guangdong, Lechang, Jiufeng , under P. massoniana , 04 October 2010, D. Wang 214 ( KUN-HKAS 86667 ) ; Guizhou, Suiyang, Qinggangtang , elev. 768 m, N28°19'24.11'' E107°09'06.69'', under P. massoniana , 25 July 2010, X. H. Wang 2404 ( KUN-HKAS 61725 ) ; Guizhou, Daozhen, Yangxi , elev. 1200 m, under P. massoniana , 28 July 2010, X. H. Wang 2417 ( KUN-HKAS 61734 ) ; Guizhou, Meitan, Xinnan, Fenghuang village , elev. 1170m, N27°32'34.48'' E107°21'03.85'', under P. massoniana , 28 September 2014, H. J. Li 140928-19 ( KUN-HKAS 88181 ) ; Guizhou, Wuchuan, Nigao , elev. 1070 m, under P. massoniana , 24 September 2014, H. J. Li 140924-29 ( KUN-HKAS 88182 ) ; Hainan, Changjiang, Bawangling , under P. latteri , 22 August 2009, N. K. Zeng 552 ( KUN-HKAS 60688 ) ; Hubei, Yingshan, Taohuachong Forest Park, elev. 960 m, N30°58'29.37'' E116°02'00.68'', 30 August 2011, X. H. Wang 3039 (holotype, KUN-HKAS 73582 ) ; Hunan, Zhangjiajie, Sanjiaguan, Yanshuijing , elev. 650 m, N29°11'44.52'' E110°17'17.12'', under P. massoniana , 15 June 2010, X. H. Wang 2356 ( KUN-HKAS 61325 ) ; Jiangxi, Jiujiang, Lushan Botanical Garden , elev. 1110 m, N29°33'00.62'' E115°58'43.34'', under P. taiwanensis , 31 August 2011, X. H. Wang 3048 ( KUN-HKAS 73591 ) ; Shandong, Qingdao, Lao Mt., Beijiushui , elev. 400 m, N36°12'18.72'' E120°36'15.69'', under P. thunbergii , 18 August 2011, X. H. Wang 2987 ( KUN-HKAS 73543 ) ; Sichuan, Emei, Hongzhushan , elev. 550 m, N29°33'42.85'' E103°26'37.05'', under P. massoniana , 10 September 2010, X. H. Wang 2769 ( KUN-HKAS 61965 ) .

Figures

FIGURE 3. Basidiocarps of Lactarius vividus, L. akahatsu and L. deliciosus, showing the subdistant to distant lamellae in L. vividus in contrast with the crowded lamellae in the other two species. A: L. vividus (KUN-HKAS 73591, holotype); B: L. vividus, in dry habitat (KUN-HKAS 61742); C: L. vividus, old basidiocarps (KUN-HKAS 61725); D: L. vividus, undiscoloring basidiocarps (KUN-HKAS 61965); E: L. vividus, undiscoloring basidiocarp (KUN-HKAS 61325); F: L. vividus, with rich-colored subdistant lamellae and evenly colored stipe (KUN-HKAS 73576); G: L. akahatsu, with crowded lamellae (KUN-HKAS 61764); H: L. deliciosus, with crowded lamellae (KUN-HKAS 61910).

FIGURE 4. Lactarius vividus (all from holotype except for C from KUN-HKAS 73591). A: basidiospores, B. hymenium, C: pleuromacrocystidia, D: pleuropseudocystidia; E. lamellar edge, F. pileipellis. (A: scale bar = 5 μm, B–F: scale bars = 20 μm).