Leptographium ningerense R.Chang & Z.W.de Beer

Chang, Runlei, Duong, Tuan A., Taerum, Stephen J., Wingfield, Michael J., Zhou, Xudong & Beer, Z. Wilhelm de, 2017, Ophiostomatoid fungi associated with conifer-infesting beetles and their phoretic mites in Yunnan, China, MycoKeys 28, pp. 19-64 : 35-36

Leptographium ningerense R.Chang & Z.W.de Beer sp. nov. Fig. 11

Etymology.

The epithet ningerense refers to the Ning’er county where all isolates of this taxon were collected.

Description.

Sexual state not observed. Asexual state, conidiophores occurring singly or in groups of up to 3, macronematous, mononematous, erect, arising directly from the mycelium, (93.5-) 141.5-195.5 (-210.5) μm long. Rhizoids present. Stipes dark olivaceous, 4-6 septa, not constricted at septa, (66-) 119.5-142 (-159) μm long. Apical cells not swollen at apex, (3-) 5-6.5 (-7) μm wide. Basal cells occasionally swollen at apex, (5.5-) 7-10 (-11.5) μm wide. Conidiogenous apparatus (28-) 35-58 (-70) μm long, excluding the conidial mass, with multiple series of cylindrical branches. Primary branches olivaceous, smooth, cylindrical, not swollen at apex, aseptate, arrangement of primary branches was Type B-two or more branches, (12.5-) 14.5-18 (-19.5) × (3.5-) 4 –5.5(– 6.5) μm. Secondary branches light olivaceous, frequently swollen at apex, aseptate, (6.5-) 9 –13(– 15) × (3.5-) 4-5 (-5.5) μm. Tertiary branches light olivaceous, aseptate, (7-) 8-10 (-12) × (3-) 3.5-4.5 (-5) μm. Conidiogenous cells discrete, hyaline, 2-3 per branch, aseptate, cylindrical, tapering slightly at the apex, (10.5-) 12-17.5 (-20.5) × (2-) 2-2.5 (-3) μm. Conidia hyaline, aseptate, elliptical, (3-) 3.5-5.5 (-6.5) × (1.5-) 2-3 (-4) μm.

Culture characteristics.

Colonies on 3% OA flat, hyaline at the beginning, then becoming light olivaceous to dark olivaceous. Colonies hyaline at the beginning, then becoming dark olivaceous. Mycelium superficial on the 3% OA with olivaceous aerial mycelium. Colony margin smooth. Conidiophores forms abundantly in clusters on OA. Colonies on 2% MEA flat, reaching 76 mm diam in 10 d at 25 °C. No growth observed at 5 and 35 °C. Optimal temperature for growth 25 °C, reaching 30.5 mm in diam. in 7 days.

Type material.

CHINA, Yunnan Province, Puer City, from Schwiebea (Jacotietta) taiwanensis hyperphoretic on Coccotrypes cyperi on Pinus kesiya bark, 16 Sep. 2010, S.J.Taerum, herbarium specimen of dried culture, PREM 61545 (holotype), CMW41786 = CBS139663 (ex-holotype culture).

Additional specimens examined.

CHINA, Yunnan province, Puer City, from Insectolaelaps sp. 1 in Orthotomicus angulatus on Pinus kesiya bark, 17 Sep. 2010, S.J.Taerum, PREM 61546, CMW41831 = CBS139664.

Host.

Pinus kesiya .

Beetle vectors.

Polygraphus szemaoensis .

Mite vectors.

Dendrolaelaps sp. 1 (phoretic on Coccotrypes cyperi ), Dendrolaelaps sp. 2 (phoretic on Coccotrypes cyperi and Cyrtogenius luteus ), Schwiebea (Jacotietta) taiwanensis (phoretic on Coccotrypes cyperi ), Insectolaelaps sp. 1 ( Orthotomicus angulatus ).

Distribution.

At present known only from Yunnan, China.

Notes.

L. ningerense is morphologically similar to L. pineti , but grows much more rapidly, reaching 30 mm in 7 d on 2% MEA at 25 °C while L. pineti reaches a diameter of only 15 mm in 6 d. However, the two species are best distinguished with BT, EF and CAL sequences.