Clavulina pallida Yue Gao, Hao Zhou, & C. L. Hou, 2024

Gao, Yue, Tong, Xin, Zhou, Hao, Wang, Hai-Qi, Li, Cheng & Hou, Cheng-Lin, 2024, Three new species of the genus Clavulina (Hydnaceae, Cantharellales) from North China based on morphological and phylogenetic analysis, MycoKeys 108, pp. 75-94 : 75-94

Clavulina pallida Yue Gao, Hao Zhou, & C. L. Hou sp. nov.

Figs 2 F – I , 3 E – G , 6

Diagnosis.

Clavulina pallida differs from known Clavulina species in its white to pale cream white basidiomata, with somewhat orange tips, basidiospores 7.0–9.7 × 6.4–8.6 μm, basidia 34.2–48.5 × 4.8–6.3 μm, postpartal septa present, and clamp connections present.

Etymology.

The epithet “ pallida ” refers to the basidiomata being pale white.

Type.

China • Beijing, Miyun District, Heilongtan ; 40 ° 35 ' 30 " N, 116 ° 46 ' 20 " E, alt. 397 m; 27 Aug. 2021; C. L. Hou, G. Q. Cheng, R. T. Zhang ( BJTC C 669 ); GenBank nrITS: PP 835329 , nrLSU: PP 835342 , rpb 2: PP 889515 .

Description.

Basidiomata coralloid, solitary or scattered; individual basidiomata 17–38 mm tall, 1.8–10 mm wide across branches, simple or sparsely branched one to two times, monopodial or irregularly dichotomous toward branch apices and monopodial or dichotomous at the base, branches subterete or subclavate to fattened and somewhat flattened with age, smooth or rough, branch tips are rounded when young, gradually become pointed with age; white (# ffffff) to pale cream white (# fffaef) when fresh and tips somewhat orange (# ff 9000), brownish orange (# cd 8400) when dry. Stipes generally distinct, 7–14 mm long, 1.5–4 mm wide, subcylindrical or flattened, white (# ffffff) to pale cream white (# fffaef). Hymenium amphigenous, somewhat wrinkled.

Basidiospores [131 / 10 / 6] (6.6 -) 7.0–9.7 (- 10.1) × (6.0 -) 6.4–8.6 (- 10.1) μm, Q = 1.00–1.24 (- 1.29), Q m = 1.10 ± 0.06, globose to subglobose, smooth, hyaline in H 2 O and KOH, thin-walled, inamyloid, with a 0.6–1.1 μm irregular hilar appendix, and one large oleiferous guttule. Basidia (31.8 –) 34.2–48.5 (- 55.3) × 4.8–6.3 (- 7.6) μm, clavate to subcylindrical, tapering from apex to base; postpartal septa present in most basidia, which occurred 10–22 μm below basidia tips; two sterigmata occur per basidium, 3.7–6.2 μm long, and cornute. Basidioles abundant, subclavate to subcylindrical. Tramal hyphae in stipe smooth, thin walled, hyaline in KOH, 3.3–6.2 μm wide, not inflated; tramal hyphae in branch hyaline and thin-walled, 2.8–6.7 (- 9.0) μm wide; clamp connections abundant. Hyphal system monomitic. Cystidia absent.

Habit, habitat, and distribution.

Solitary or scattered in humus layers on soils in broad-leaved deciduous forests associated with Carpinus L. and Castanea Mill. Basidiomata generally occur from July to August and are currently known from Beijing and Hebei Province, China.

Additional specimens examined.

China • Beijing, Pinggu District, Zhenluo Mountain Villa ; 40 ° 20 ' 24 " N, 117 ° 8 ' 57 " E, alt. 294 m; 20 Aug. 2021; C. L. Hou, G. Q. Cheng, R. T. Zhang ( BJTC C 229 ) ; China • Beijing, Yanqing District, Heibei village ; 40 ° 25 ' 48 " N, 116 ° 14 ' 44 " E, alt. 456 m; 11 Aug. 2018; X. Y. Shen, B. D. He, K. B. Huang ( BJTC S 062 ) ; China • Beijing, Changping District, Yanshou Temple ; 40 ° 22 ' 24 " N, 116 ° 19 ' 22 " E, alt. 276 m; 14 Aug. 2019; C. L. Hou, H. Zhou, G. Q. Cheng ( BJTC ZH 0056 ) ; same location • 40 ° 22 ' 6 " N, 116 ° 19 ' 19 " E, alt. 215 m; 17 Aug. 2021; H. Zhou, X. Y. Shen, X. B. Huang ( BJTC ZH 0810 ) ; China • Hebei Province, Zunhua City, Wanfo Garden ; 40 ° 11 ' 34 " N, 116 ° 37 ' 1 " E, alt. 144 m; 22 Aug. 2021; H. Zhou, X. Y. Shen, X. B. Huang ( BJTC ZH 1055 ) .

Notes.

In the phylogenetic analyses (Fig. 1 .), C. pallida is phylogenetically close to Clavulina mahiscolorata . C. mahiscolorata also has white basidiomata, but turns orange when dried, larger basidia (56–74 × 6–8 µm) are present ( Pérez-Pazos et al. 2019). As described in the current record of the genus Clavulina , in terms of macroscopic features, Clavulina rugosa is closely related to C. pallida , with simple or sparsely branched basidiomata. However, C. rugosa differs from C. pallida in that it has longitudinally wrinkled surfaces of basidiomata and relatively large basidiospores (9–14 × 8–12 µm) ( Corner 1950; Olariaga et al. 2009). Clavulina livida generally shares similar simple basidiomata with C. pallida , but the former has grayish olive to dark grayish olive basidiomata, branch tips becoming pale pinkish cinnamon to chestnut with age, larger basidiospores (11.6–12.9 × 10.7–12.5 µm) and basidia (51.5–76.7 × 7.0–12.3 µm) ( He et al. 2016). Clavulina caespitosa T. W. Henkel, Meszaros & Aime differs from C. pallida in its simple basidomata in cespitose clusters, free or slightly fused basally, apex sharply acuminate, larger basidiospores (8.5–10.5 × 7–9.5 µm) and basidia (81–98 µm long, apex 6.3–7.5 µm, at base 3.5–5 µm), and postpartal septa not observed ( Henkel 2005).

Figures

Figure 1. Phylogenetic tree generated from a ML analysis based on combined nrITS-nrLSU- rpb 2 sequences. Numbers representing Maximum Likelihood bootstrap support (MLBS ≥ 75 %, right) and significant Bayesian posterior probability (BPP ≥ 0.95, left) are indicated above the nodes. Novel sequences are printed in bold. Voucher specimens and localities where the specimens were collected are provided behind the species names.

Figure 2. Morphology of Basidiomata A – C Clavulina chengdeensis (A BJTC TX 646 holotype B BJTC ZH 1205 C BJTC ZH 1225) D – E Clavulina griseoviolacea (D BJTC ZH 0998 holotype E BJTC ZH 1653) F – I Clavulina pallida (F BJTC C 669 holotype G BJTC S 062 H BJTC ZH 1055 I BJTC C 229). Scale bars: 1 cm.

Figure 3. Morphology of Basidiomata A – C Clavulina chengdeensis (A BJTC TX 646 holotype B BJTC ZH 1205 C BJTC 0249) D Clavulina griseoviolacea (D BJTC ZH 0998 holotype) E – G Clavulina pallida (E BJTC C 669 holotype F BJTC S 062 G BJTC ZH 0056). Scale bars: 1 cm.

Figure 6. Microscopic characteristics of Clavulina pallida A basidiospores B basidia C tramal hyphae. Scale bars: 10 µm.