Conocybe rubrocyanea T. Bau & H. B. Song, 2025

Song, Han-bing & Bau, Tolgor, 2025, Three new species and a new record of Conocybe section Pilosellae (Bolbitiaceae, Agaricales) from Jilin Province, China, MycoKeys 114, pp. 67-94 : 67-94

Conocybe rubrocyanea T. Bau & H. B. Song sp. nov.

Figs 2 I – M , 7 , 8

Etymology.

“ rubrocyanea “ refers to basidiomata that have a reddish hue when fresh and a bluish hue when dry.

Holotypus.

China, • Jilin Province, Jilin City, Jiaohe City, Shansongling , 30 July 2023, 43°32'14"N, 127°01'33"E, alt. 610 m, Shi-En Wang, E 2307268 ( FJAU 65123 ) .

Diagnosis.

Conocybe rubrocyanea , when fresh, displays a mainly red color on the pileus, transitioning to blue upon drying. Basidiospores are lentiform, ellipsoid to oblong, frontal view near hexagonal, side view phaseoliform, cheilocystidia clavate, utriform, ellipsoid, or fusiform on one side near the edge of the pileus, and lecythiform on the side near the stipe, and some pileipellis cells contain blue lilac pigment.

Description.

Basidioma mycenoid. Pileus diameter 0.5–2.0 cm, initially hemispherical, conical, later obtusely conical, with straight, undulate margin. When fresh, pileus salmon orange (RAL 2012), antique pink (RAL 3014) to rose (RAL 3017), tomato red (RAL 3013) to pearl ruby red (RAL 3032), and when dry, it becomes slate gray (RAL 7015), brown gray (RAL 7013) to cobalt blue (RAL 5013). Pileus hygrophanous, covered in distinct pubescence and striations that extend up to one-third towards the center. Context thin, salmon orange (RAL 2012) to light ivory (RAL 1015), no specific odor or taste. Lamellae ventricose, adnexed to narrowly adnate, moderately crowded, unequally long, initially light ivory (RAL 1015) to ivory (RAL 1014), later pastel yellow (RAL 1034) to ochre-brown (RAL 8001), with inconspicuous, slightly eroded edges. Stipe 2.0–8.0 cm long, 1.0–4.0 mm thick, cylindrical, clay brown (RAL 8003), rose (RAL 3017), antique pink (RAL 3014) to pearl ruby red (RAL 3032), surface pruinose and pubescent, longitudinally striate, base bulbous.

Basidiospores (60 / 3 / 3) 8–11.5 (– 12.5) × 5–7.5 × 5–6 (– 6.5) μm, Q = (1.33 –) 1.42–2.08 (– 2.14), Qm = 1.76 (± 0.17), lentiform, ellipsoid to oblong, frontal view near hexagonal, side view phaseoliform, slight constriction at center, with thick walls, containing oil droplets, germ pore diameter 0.5–2.0 μm, basidiospores in KOH solution ochre brown (RAL 8001) to copper brown (RAL 8004). Basidia (13 –) 15–26 (– 27) × 8–11 (– 12) μm, broadly clavate to clavate, 4 (2) - spored, with sterigmata measuring 2–6 μm in length, basidia contain vacuolar contents. Cheilocystidia (14 –) 15–27 (– 28) × (6 –) 7–14 (– 15) μm, clavate, utriform, ellipsoid, or fusiform on one side near the edge of the pileus, and lecythiform on the side near the stipe, with capitula 3–6 μm wide. Caulocystidia elliptical to oblong, lageniform, long-necked lageniform, nettle hair-shaped, conical, fusiform, cylindrical, clavate, narrowly utriform to utriform, (10 –) 12–82 (– 85) × (5 –) 6–16 μm, capilliform cystidia may exceed 100 μm, with rare occurrences of lecythiform and sub-lecythiform cystidia at the apex. Pileipellis hymeniform, composed of spheropedunculate and fusiform cells (25 –) 27–53 (– 54) × (14 –) 15–28 (– 29) μm, some containing blue lilac (RAL 4005) pigment, with yellow pigment at the base. Pileocystidia (21 –) 23–55 (– 60) × 4–23 μm, with long-necked lageniform, lecythiform, cylindrical, and nettle hair-shaped forms, and capilliform cystidia can exceed 100 μm. Clamp connections are rare in all tissues. It shows a positive reaction with ammonia, forming diamond-shaped crystals.

Habitat.

Scattered or grouped in mixed forests during the summer season, on cow dung.

Known distribution.

Jilin Province, China.

Additional specimens measured.

China, • Jilin Province, Jilin City, Jiaohe City, Shansongling , 26 July 2022, 43°32'02"N, 127°02'36"E, alt. 580 m, Han-Bing Song, S 22072618 ( HMJAU 64964 ) ; • Jilin City, Jiaohe City, Shansongling , 29 July 2023, 43°32'20"N, 127°03'09"E, alt. 530 m, Shi-En Wang, E 2307247 ( FJAU 71648 ) ; • Jilin City, Jiaohe City, Shansongling , 30 July 2023, 43°32'20"N, 127°01'50"E, alt. 550 m, Shi-En Wang, Xia Wang, Si-Ying Li, W 23073002 ( FJAU 71649 ), W 23073003 ( FJAU 71650 ), W 23073004 ( FJAU 71651 ), E 2307277 ( FJAU 71652 ), L 23073033 ( FJAU 71653 ) ; • Jilin City, Jiaohe City, Shansongling , 26 August 2023, 43°32'26"N, 127°02'23"E, alt. 550 m, Zheng-Qing Chen, Mu Liu, Hong Cheng, Q 2382626 ( FJAU 71654 ), LM 230864 ( FJAU 71655 ), C 2382603 ( FJAU 71656 ), C 2382605 ( FJAU 71657 ), C 2382611 ( FJAU 71658 ), C 2382615 ( FJAU 71659 ) ; • Jilin City, Huadian City, Redstone National Forest Park , 28 August 2023, 42°58'08"N, 127°03'36"E, alt. 430 m, Xian-Yan Zhou, Y 2382804 ( FJAU 71660 ) .

Notes.

Conocybe rubrocyanea can be differentiated from species with near hexagonal basidiospores in sect. Pilosellae , such as C. hexagonospora , C. brunneidisca , C. lentispora , C. brunneoaurantiaca , C. pulchra and C. angulispora , by presence of red color tone on the pileus ( Hausknecht 2009). Conocybe rubrocyanea is closely related to C. incarnata (Jul. Schäff.) Hauskn. & Arnolds and C. muscicola , and they are easily confused in macroscopic morphology. However, C. incarnata and C. muscicola basidiospores are not lentiform or hexagonal, and pileipellis cells lack blue lilac pigment ( Arnolds and Hausknecht 2003).

Figures

Figure 2. Basidiomata of Conocybe sect. Pilosellae species A C. verna (FJAU 65117 T) B C. verna (FJAU 65118) C, D C. verna (FJAU 65119) E, F C. angulispora (FJAU 65120 T) G C. angulispora (FJAU 65122) H C. angulispora (FJAU 65121) I C. rubrocyanea (FJAU 65123 T) J C. rubrocyanea (FJAU 71654) K C. rubrocyanea (FJAU 71658) L C. rubrocyanea (FJAU 71652) M C. rubrocyanea (FJAU 71650) N – P C. hexagonospora (FJAU 71661), Scale bars: 1 cm, T = holotype.

Figure 7. Conocybe rubrocyanea (FJAU 65123) A basidiomata B basidiospores in KOH C hymenium and subhymenium D cheilocystidia E stipitipellis F pileipellis. Scale bars: 1 cm (A); 10 μm (B – F).

Figure 8. Microscopic structure images of Conocybe rubrocyanea (FJAU 65123) A basidiospores, B basidia C cheilocystidia D stipitipellis E pileipellis. Scale bars: 10 μm (A – E).