Leptobacillium muralicola Jing Z. Sun, Qin Y. Ge, Zhi B. Zhu & Xing Z. Liu, 2019

Sun, Jing-Zu, Ge, Qin-Ya, Zhu, Zhi-Bao, Zhang, Xiao-Ling & Liu, Xing-Zhong, 2019, Three dominating hypocrealean fungi of the ‘ white mold spots’ on acrylic varnish coatings of the murals in a Koguryo tomb in China, Phytotaxa 397 (3), pp. 225-236 : 232-233

Leptobacillium muralicola Jing Z. Sun, Qin Y. Ge, Zhi B. Zhu & Xing Z. Liu sp. nov. ( Fig. 4 )

Index Fungorum number: IF554781

Etymology: muralicola , the stem mural - refers to the substrate that the type strain was isolated, the ending -cola means “dweller, inhabit”.

Holotype: HMAS 247818

Saprobic on substrate. Asexual morph: Colonies on PDA, white, greyish white to greenish white. Reverse pale luteous, milky white to dark buff, orange to orange-brown, ochraceous, sometimes with yellow pigment diffusing into the agar. Conidiophores macronematous, mononematous, mainly long solitary phialides, rarely with branches of one or two phialides. Phialides 20–45 μm (x = 32 μm, n = 30), tapering from 1–2 μm (x = 1.8 μm, n = 30) near the base to 0.5–0.7 μm (x = 0.6 μm, n = 30) at the tip. Conidia acrogenous, amerospores, forming very long, slender and inconspicuous chains, narrowly cylindrical (rod-shaped) to slightly fusiform, 4.5–6 × 1–2 μm (x = 5.5 × 1.6 μm, n =

50). The first-formed conidium is usually shorter, obovoid to pyriform, with a rounded distal end. Chlamydospores absent. Octahedral crystals undetermined. The optimum temperature for growth 18–25 °C.

Culture characteristics: Colonies on PDA reaching 10–20 mm in diameter in 10 days at 20 °C, white, greyish white to greenish white. Reverse pale luteous, milky white to dark buff, orange to orange-brown, ochraceous, sometimes with yellow pigment diffusing into the agar.

Material examined: CHINA. Jilin Province, JiAn City, WKT5 tomb, associated with‘white moldy spots’ on B01-6

coat, 30 August 2016. holotype: (HMAS 247818), ex-type strain: CGMCC 3.19014, living culture CGMCC 3.19015,

CGMCC 3.19016.

Notes: Phylogenetic analysis presented that Leptobacillium muralicola represents a new species responding to the 39 bp differences in ITS and 15 bp differences in LSU against that of L. leptobactrum . Additionally, L. muralicola differs from L. leptobactrum by the colonial color changed from greyish white to greenish white over time. The ratio of conidial length/width of L. muralicola is (2–6) less than L. leptobactrum (3–10) ( Zare & Gams 2016).

Figures

FIGURE 4. Leptobacillium muralicola (HMAS 247818, holotype). a Colonies on PDA after 14 days, forward (left), reverse (right). b Mycelia. c, f Conidiophores with conidia. d, e. Conidiogenous cells. g, h. Conidia in chain. i–k Conidia. Scale bars: b = 1 cm; c = 100 μm; d–i = 10 μm; j, k = 5 μm.