Nectria pseudotrichia Berk. & M.A. Curtis, J. Acad. nat. Sci. Philad., N.S. 2(6): 289 (1854) [1853]

MycoBank number: MB 206961; Index Fungorum number: IF 206961; Facesoffungi number: FoF 01990; Fig. **

Saprobic on dead twigs attached to Anomianthus dulcis. Sexual morph: Mycelium not visible around ascomata or on host. Stromata erumpent through epidermis, pseudoparenchymatous, intergrading with ascomatal wall. Ascomata 230–260 μm high × 240–280 μm diam. ( = 250 × 270 µm, n = 10), orangish brown, subglobose to globose, superficial on stroma, solitary or caespitose, sometimes cupulate upon drying, papillate, apical region darker, smooth to rough. Ascomatal wall 45–65 μm wide, composed of two regions: outer region 35–55 μm wide, 3–5 layers of hyaline, cells of textura prismatica; inner region 10–15 μm wide, several layers of yellow, cells of textura angularis. Asci 45–70 × 10–16 ( = 60 × 13 µm, n = 20), 8-spored, unitunicate, clavate, with inconspicuous ring at apex. Ascospores 23–32 × 7–11 ( = 25 × 8.5 µm, n = 30), hyaline, obovoid, ellipsoidal to fusiform, muriform with 5–7 transverse septa and 1-2 longitudinal septum, straight, sometimes slightly curved, rounded at both ends. Asexual morph: see Hirooka et al. (2012).

Culture characteristics – Colonies on PDA reaching 40 mm diameter after 1 weeks at 25°C, colonies from above: circular, margin entire, flat, surface cottony with aerial mycelium, white; reverse: cream.

Material examined – THAILAND, Chiang Rai Province, dead twigs attached to Anomianthus dulcis (Annonaceae), 4 April 2019, N. I. de Silva, AND25 (MFLU 21-0237), living culture, MFLUCC 21-0203.

Known hosts and distributionNectria pseudotrichia occurs on numerous host plants and distributed in worldwide including Schinus myrtifolia in Argentina, Litchi chinensis in Australia, Persea americana in Bolivia, Hydrangea sp., Mallotus sp. in China, Erythrina indica in India, Stilbella cinnabarina in Indonesia, bark of dead wood in Japan, woody substrate in Malaysia, Theobroma cacao in Papua New Guinea, newly killed wood in Taiwan, Albizia julibrissin, Ficus sp., Jussiaea peruviana in USA (Hirooka et al. 2012).

GenBank numbers – ITS: OK284455, LSU: OK179727, tef1: OK274276, tub2: OK430881.

NotesNectria pseudotrichia can be distinguished from other species in the genus in having combination of muriform ascospores and a synnematous anamorph (Hirooka et al. 2012). Morphology of the new isolate differs from the type N. pseudotrichia. Ascomata of the new isolate (230–260 μm high × 240–280 μm diam.) are smaller than the type (333–548 μm high × 296–534 μm diam.) (Hirooka et al. 2012). Asci of the new isolate (45–70 × 10–16 μm) are slightly smaller than the type (65–125 × 13–32 μm) (Hirooka et al. 2012). However, ascospores of the new isolate (23–32 × 7–11 μm) and the type (14.8–41.3 × 4.6–15 μm) have overlapping size range.

Nectria pseudotrichia is commonly found as a saprobe in tropical and warm temperate regions (Hirooka et al. 2012). This fungus can also be a facultative parasite because Becker (2003) confirmed its pathogenicity on Pyrus pirifolia in Brazil. Nectria pseudotrichia has been recorded from Thailand such as on bark of recently dead tree, dead twigs of unknown plants and on Acacia sp. in Saraburi Province, on decorticated wood of unknown plants in Phetchaburi Province, on bark of recently dead tree of unknown plants in Prachinburi Province (Hirooka et al. 2012). However, N. pseudotrichia has not been recorded from Anomianthus dulcis (Annonaceae) in Thailand (Farr & Rossman 2021). In the present study we report the first record of N. pseudotrichia from Anomianthus dulcis in Thailand.

Figure ** Nectria pseudotrichia (MFLU 21-0237). a The specimen. b, c Appearance of perithecia on substrate. d, e Sections through perithecia. f, g Peridium. h Paraphyses. i–k Asci (j, k stained with Congo red). l–p Ascospores. Scale bars: b = 500 μm, c = 200 μm, d, e = 50 μm, f–k = 20 μm, l–p = 10 μm.