Verruconis hainanensis Z.F. Yu & M. Qiao

Qiao, Min, Tian, Weiguang, Castaneda-Ruiz, Rafael F., Xu, Jianping & Yu, Zefen, 2019, Two new species of Verruconis from Hainan, China, MycoKeys 48, pp. 41-53 : 41

Verruconis hainanensis Z.F. Yu & M. Qiao sp. nov. Figure 2

Etymology.

Latin, hainanensis, refers to the collection locality.

Description.

Colonies on CMA medium compact, restricted, brown to fuliginous, 13 mm at 20 °C after 20 days, 16 mm at 25 °C, 11 mm at 30 °C, no growth at 35 °C. Aerial hyphae subhyaline to brown, smooth- or somewhat rough-walled. Conidiophores semi-macronematous, mononematous, sometimes slightly moniliform, unbranched or branched at the apex with 2-4 divergent conidiogenous cells, brown basal cell, pale brown branches, smooth, up to 25 μm long. Conidiogenous cells mostly monoblastic, discrete, scattered, brown to fuliginous or pale brown, lageniform to ampulliform, pale brown, 3.4-6.0 × 2.2-3.6 μm, with a fimbriate denticle-like at the conidiogenous locus after rhexolytic conidial secession. Conidia solitary, acrogenous, fusiform, rostrate at the apical cell, 3-septate, dark at the septa, coarsely verrucose, more or less equilateral, slightly constricted at the median septum, bicoloured, with brown middle cells and subhyaline end cells, 23-30.2 × 3.6-5.7 μm, with an inconspicuous basal frill.

Type.

CHINA. From leaves of an unidentified dicotyledonous plant submerged in a stream, Qixianling, Hainan Province, 18°68'N, 109°69'E, 902 m alt., 16 June 2016, Z.F. Yu (dried slide YMFT 1.04165, holotype; live culture YMF 1.04165 -ex-type culture; CGMCC–3.18974– isotype).

Notes.

Verruconis hainanensis shares the fusiform conidial shape with some described Scolecobasidium species, such as: S. cateniphorum Matsush., S. caffrum Matsush., S. houhense D.W. Li & Jing Y. Chen and S. tropicum Matsush., but all these taxa are readily distinguishable from the new Chinese species. Specifically, S. cateniphorum is distinguished by its 1-septate, smooth or inconspicuous echinulate, 10-24 × 2-3.5 μm conidia ( Matsushima 1975). S. caffrum and S. tropicum both have 2-septate conidia, but S. caffrum has conidia mostly smooth or inconspicuously rough, 20-35 × 4-7.5 μm, with pale brown central and subhyaline end cells ( Matsushima 1996) and S. tropicum has conidia with smooth or inconspicuous verruculose, smaller, 14-20 × 4.5-6 μm, with pale brown central and subhyaline end cells ( Matsushima 1983). S. houhense with 3-septate conidia is superficially similar to V. hainanensis , but S. houhense is characterised by minutely verruculose conidia, 26-31 × 4.5-5.5 μm, brown, with central cells darker than end cells and slightly protuberate and with a dark basal scar and its conidiogenous cells and conidiophores are different from those of V. hainanensis ( Li et al. 2010). The distinct dark scar, described from S. houhense , has been reported by Matsushima (1975) in Nakataea fusispora (Matsush) Matsush., but it is absent in V. hainanensis .