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

Figs 2 A – C , 3 A – C , 4

Diagnosis.

Clavulina chengdeensis differs from known Clavulina species in its white to dirty white basidiomata with somewhat pale orange tips, somewhat wrinkled hymenium, basidiospores 6.1–9.6 × 5.6–7.9 μm, basidia 40.1–58.7 × 4.5–7.0 μm, postpartal septa present, and clamp connections present.

Etymology.

The epithet “ chengdeensis ” refers to the specimens collected from Chengde city.

Type.

China • Hebei Province, Chengde city, Xiaolabagou ; 40 ° 57 ' 24 " N, 116 ° 27 ' 12 " E, alt. 1240 m; 13 Sep. 2023; H. Zhou, Y. Gao & X. Tong ( BJTC TX 646 ); GenBank nrITS: PP 835331 , nrLSU: PP 835344 , rpb 2: PP 889517 .

Description.

Basidiomata coralloid, solitary or gregarious in cespitose clusters; clusters 12–24 mm tall, 10–26 mm wide across branches and forming 3–5 ranks in multiple planes; individual basidiomata 14–40 mm tall, 4–11 mm wide, simple or sparsely branched one time, branching pattern polychotomous to dichotomous ascending, branches subterete or subclavate and somewhat flattened with age, rough, branch tips rounded when young, gradually become pointed with age; white (# ffffff) to dirty white (# fff 9 eb) when fresh and somewhat pale orange (# ffeab 8), cream white (# fff 2 d 2) to light grayish orange (# f 6 e 4 d 0) when dry. Stipes generally distinct, 5–15 mm long, 1.5–4 mm wide, subcylindrical or flattened, concolor with branches. Hymenium amphigenous, somewhat wrinkled.

Basidiospores [87 / 9 / 4] (5.7 -) 6.1–9.6 (- 11.0) × 5.6–7.9 (- 8.5) μm, Q = 1.00–1.25 (- 1.31), Q m = 1.04 ± 0.02, globose to subglobose, smooth, hyaline in H 2 O and KOH, thin-walled, inamyloid, with a 0.6–1.0 μm irregular hilar appendix, and one large oleiferous guttule. Basidia (34.7 –) 40.1–58.7 (- 62.3) × 4.5–7.0 (- 8.3) μm, clavate to subcylindrical, tapering from apex to base; postpartal septa present in most basidia, occurring 11–30 μm below basidia tips; two sterigmata occur per basidium, 5.1–7.5 μm long, and cornute. Basidioles abundant, subclavate to subcylindrical. Tramal hyphae in stipe smooth, with slightly thickened walls, hyaline in KOH, 4.0–7.7 μm wide, sometimes inflated to 9.3 μm wide; tramal hyphae in branches hyaline, thin-walled, sometimes inflated tramal hyphae 3.7–8.5 (- 10.4) μm wide; clamp connections abundant. Hyphal system monomitic. Cystidia absent.

Habit, habitat, and distribution.

Solitary or gregarious caespitose in humus layers on soils in broad-leaved deciduous forests associated with Castanea Mill. , Betula L., and Platanus L. Basidiomata generally occur from July to September; currently known from Hebei Province and Beijing, China.

Additional specimens examined.

China • Beijing, Yanqing District , Songshan National Nature Reserve; 40 ° 30 ' N, 115 ° 48 ' E, alt. 652 m; 16 Sep. 2017; C. L. Hou, H. Zhou, J. Q. Li ( BJTC 0249 ) ; China • Beijing, Huairou District, Labagoumen Nature Reserve ; 40 ° 39 ' 24 " N, 116 ° 27 ' 14 " E, alt. 1225 m; 25 Aug. 2021; H. Zhou, X. Y. Shen, X. B. Huang ( BJTC ZH 1205 ) ; same location • 40 ° 57 ' 17 " N, 116 ° 27 ' 3 " E, alt. 1308 m; 25 Aug. 2021; H. Zhou, X. Y. Shen, X. B. Huang ( BJTC ZH 1225 ) .

Note.

Phylogenetically, C. chengdeensis was related to C. rugosa in our analyses (Fig. 1 ). However, C. rugosa has longitudinally rugulose basidiomata, relatively large basidiospores (9–14 × 8–12 µm), basidia (40–85 × 6.9–5 µm), and sterigmata 6–9 µm long ( Corner 1950; Olariaga et al. 2009). Morphologically, C. chengdeensis is close to C. mahiscolorata . Clavulina mahiscolorata generally shares similar colors with basidiomata, but its basidiomata turn maize yellow to mandarin orange when dry and the branch surface is smooth ( Pérez-Pazos et al. 2019).

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 4. Microscopic characteristics of Clavulina chengdeensis A basidiospores B basidia C tramal hyphae. Scale bars: 10 µm.