Ophiostoma peniculi 2020

Ophiostoma peniculi Z. Wang & Q. Lu 2020

MycoBank MB 830609.

Holotype: China: Heilongjiang province, Hongxing, from Ips subelongatus infesting Larix gmelinii, Sept. 2017, Q. Lu (CXY 2013 – holotype, CFCC 52687 – ex-type culture).

Morphological description

Sexual morph not observed. Asexual morphs: pesotum-like and hyalorhinocladiellalike. Pesotum-like morph: synnemata brush-like, occurring in groups, milky white, (875–) 945–1225 (− 1290) μm long including conidiogenous apparatus, (78.5–) 81.5– 91.5 (− 94) μm wide at base. Conidiogenous cells (13.5–) 17.5–26.5 (− 32) × (1.5–) 2–2.5 μm. Conidia hyaline, smooth, cylindrical, aseptate, (4–) 5–6 (− 6.5) × 2– 2.5 μm. Hyalorhinocladiella-like morph: conidiogenous cells arising directly from aerial hyphae, (7.5–) 10.5–21 (− 33.5) × (1.5–) 2–2.5 (− 3) μm. Conidia hyaline, aseptate, smooth, cylindrical, (5–) 5.5–6.5 (− 8) × (28–) 2.5– 3.5 (− 4) μm. Cultures: Colonies on 2% MEA at 25 °C reaching 75mm diam. in 5 d, initially hyaline, the colonies edge thinning radially, becoming dark olivaceous in the centre; mycelium mostly superficial, sparsely aerial. Optimal temperature for growth at 30 °C, no growth observed at 5 °C and 40 °C.

Habitat: L. gmelinii pure plantation.

Ecology: Isolated from Ips subelongatus infesting dying Larix gmelinii and L. olgensis.

Distribution: Inner Mongolia Autonomous Region and Heilongjiang province, China.

GenBank Accession: ITS/LSU MK748198; β-tubulin gene MN896035; EF-1α MN896063; calmodulin gene MN896086

Notes: Ophiostoma peniculi, O. macroclavatum, and O. pseudocatenulatum can be distinguished from each other by the sizes of their synnemata and conidia. In decreasing order, the size ranges of their synnemata are (2184–) 3117–5172 (− 6330) μm in O. macroclavatum, (1366–) 1931–3696 (− 4534) μm in O. pseudocatenulatum and (875) 945–1224 (− 1290) μm in O. peniculi. The width ranges of their conidia are, in decreasing order, 2–2.5 μm in O. peniculi, 1.5–2 (− 3) μm in O. macroclavatum, and (0.5–) 1–1.5 (− 2) μm in O. pseudocatenulatum. Ophiostoma peniculi colonies also grow faster than the above two species on 2% MEA at 25 °C. The optimal growth temperature is also different for O. peniculi (30 °C) and O. macroclavatum (25 °C). As for O. peniculi, no growth was observed at 5 °C and 40 °C, but O. pseudocatenulatum can still grow at 5 °C (Linnakoski et al. 2016).

Reference: Wang Z, Liu Y, Wang HM et al. (2020) Ophiostomatoid fungi associated with Ips subelongatus, including eight new species from northeastern China

Ophiostoma peniculi. Morphological characteristics of O. peniculi (CFCC 52687). a–b. Five-day-old cultures on 2% MEA; c–d. Hyalorhinocladiella-like asexual morph: conidiogenous cells and conidia. e. Brush-like conidioma; f. Pesotum-like asexual morph; g–h. Conidiogenous cells of pesotum-like asexual morph and conidia. Scale bars: c–d = 10 μm; e = 400 μm; f = 200 μm; g–h = 10 μm