Lecanicillium gracile V.B. Ponizovskaya, A.A. Grum-Grzhim., Georgieva & Bilanenko, 2020

Ponizovskaya, Valeria B., Grum-Grzhimaylo, Alexey A., Georgieva, Marina L., Kokaeva, Lyudmila Y. & Bilanenko, Elena N., 2020, Lecanicillium gracile (Cordycipitaceae), a new species isolated from mineral building materials, Phytotaxa 443 (3), pp. 265-278 : 268-275

Lecanicillium gracile V.B. Ponizovskaya, A.A. Grum-Grzhim., Georgieva & Bilanenko , sp. nov.

MycoBank MB830764

Figs. 2–3

Etymology:— Latin, gracile = slender or thin; referring to slim phialides and thin mycelium.

Type:— RUSSIA. Vladimir region: Kideksha village, Church of Boris and Gleb (XII century), wall area with high moisture content and precipitation of salts at the surface, loose limestone, 13/June/2013, collected by V.B. Ponizovskaya, N.L. Rebrikova, isolated by V.B. Ponizovskaya (holotype CBS H-23932), ex-type culture Kd1 (CBS 142821).

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Culture characteristics: Colonies on PDA reaching 14–30 mm diam. in 10 days and 20–39 mm diam. in 14 days. Colonies white, cottony, centrally raised, colony surface or at least marginal parts more or less radially wrinkled, margin entire, no exudate and soluble pigments, reverse yellowish to creamish. Colonies on PCA reaching 19–24 mm diam. in 10 days and 26–31 mm diam. in 14 days. Colonies white, floccose, sometimes waxy near margin, more or less centrally raised, margin entire, submerged, no exudate and soluble pigments, reverse creamish. Colonies on MYA reaching 21–26 mm diam. in 10 days and 27–33 mm diam. in 14 days. Colonies white, cottony, more or less centrally raised, colony surface or marginal parts more or less radially wrinkled, margin entire, no exudate and soluble pigments, reverse creamish to brownish.

Phialides (6–)10–23(–33) μm long (mean ± standard deviation 15.7±5.3), basal part (0.5–)0.8–1.5 (1±0.2) μm wide, tip 0.2–0.9 μm wide (0.5±0.1), slender, tapering toward the tip, produced solitary or less often in whorls of 2–3 (rarely 4–5) on prostrate conidiophores; sometimes also produced on short erect conidiophores or secondarily formed on the preceeding phialides. Conidia formed in heads in the apex of the phialides, dimorphic, macroconidia mostly with pointed ends, fusiform to slightly falcate, smooth-walled, 1-celled, 3.6–8.0 × 1.7–0.8 μm (5.4±0.9 × 1.2±0.2), microconidia ovate, obovate, ellipsoidal, sometimes fusiform and slightly curved, smooth-walled, 1-celled, 1.1–3.3 × 0.7–1.4 μm (2.3±0.45 × 1.1±0.2). No microscopic crystals observed.

Sexual stage not observed.

Temperature optimum for growth of Kd1 (CBS 142821) is 20–23 °C (19–33 mm diam. in 14 d), reduced growth at 28 °C (5–7 mm diam. in 14 d), no growth occurring at 30 °C ( Fig. 4 ).

Temperature optimum for growth of 57-9-2 (CBS 142816) is 23–25 °C (30–38 mm diam. in 14 d), reduced growth at 33 °C (3–7 mm diam. in 14 d), no growth occurring at 35 °C ( Fig. 4 ).

Temperature optimum for growth of G4-5 (VKPM F-1421) is 23–25 °C (26–39 mm diam. in 14 d), reduced growth at 33 °C (2–3 mm diam. in 14 d), no growth occurring at 35 °C ( Fig. 4 ).

ITS differences with the closest taxa

Lecanicillium gracile (MF682448, Kd1, type) differs from L. restrictum (LT548279, CCF 5252, type) by 22 SNPs, two 1-bp deletions, three 1-bp insertions in a total of 1034 character alignment (97.4 % similarity). Lecanicillium gracile (MF682448, Kd1, type) differs from L. testudineum (LT548278, CCF 5201, type) by 24 SNPs, one 1-bp deletion, three 1-bp insertions in a total of 1033 character alignment (97.3 % similarity). Lecanicillium gracile (MF682448, Kd1, type) differs from L. coprophilum (MH177616, CGMCC 3.18986, type) by 22 SNPs, three 1-bp deletions, one 1-bp insertion in a total of 541 character alignment (95.2 % similarity). Lecanicillium gracile (MF682448, Kd1, type) differs from P. album (LC092880, CBS 504.83, type) by 15 SNPs, seven deletions (five 1-bp deletions and two 4-bp deletions), one 1-bp insertion in a total of 548 character alignment (94.7 % similarity).

TEF1a differences with the closest taxa

Lecanicillium gracile (MN602801, Kd1, type) differs from L. restrictum (LT626943, CCF 5252, type) by 33 SNPs in a total of 459 character alignment (92.8 % similarity). Lecanicillium gracile (MN602801, Kd1, type) differs from L. testudineum (LT626942, CCF 5201, type) by 27 SNPs in a total of 459 character alignment (94.1 % similarity). Lecanicillium gracile (MN602801, Kd1, type) differs from L. coprophilum (MH184587, CGMCC 3.18986, type) by 26 SNPs in a total of 412 character alignment (93.7 % similarity).

Figures

FIGURE 2. Lecanicillium gracile (CBS 142821, ex-type). a–c 14 days-old (25 °C, dark regime) colonies on PDA, PCA and MYA in 9 cm Petri plates, respectively. d–f Reverses of 14 days-old (25 °C, dark regime) colonies on PDA, PCA and MYA in 9 cm Petri plates, respectively. g–h Phialides and conidia (SEM). i–j Conidia. Scale bars: g–j = 10 μm.

FIGURE 3. Lecanicillium gracile (CBS 142821, ex-type). a–c Prostrate conidiophores with solitary phialides or phialides produced in whorls (LM). d Short erect conidiophore with phialides (LM). e–f Prostrate conidiophores with phialides produced in whorls (LM). g–h Phialides secondarily born on the preceeding phialides (LM). i Conidia (LM). j A drawing of prostrate conidiophores with phialides. k A drawing of conidiophores with phialides and conidia. Scale bars: a = 50 μm; b–k = 10 μm.

FIGURE 4. Temperature-dependent growth profiles of Lecanicillium gracile isolates. Colony diam. after 14 d on PDA (n=3, mean±SD).