Allantophomopsiella

 Crous, IMA Fungus 5: 180. 2014. .

Fig. 1. Allantophomopsiella pseudotsugae (CBS 841.91). A. Conidiomata forming on autoclaved barley leaves. B–E. Conidiogenous cells giving rise to conidia. F. Conidia. Scale bars: A = 300 μm; others = 10 μm. Pictures taken from Crous et al. (2014b).

Classification: Leotiomycetes, Leotiomycetidae, Phacidiales, Phacidiaceae.

Type species: Allantophomopsiella pseudotsugae (M. Wilson) Crous., basionym: Phomopsis pseudotsugae M. Wilson. Lectotype designated here: material deposited in Royal Botanic Garden Edinburgh, E00414771. Epitype and ex-epitype strain designated here: CBS H-23354, CBS 320.53.

DNA barcodes (genus): ITS, LSU. DNA barcodes (species): ITS, rpb2. Table 1.

Conidiomata up to 600 μm diam, pycnidial, immersed, becoming erumpent, irregularly multilocular, dark brown, ostiolate; conidiomatal wall composed of 3–4 layers of dark brown cells, textura angularis. Conidiophores arising from inner layer of conidioma, branched, septate, at times reduced to conidiogenous cells. Conidiogenous cells integrated or discrete, ampulliform to subcylindrical or lageniform, hyaline, smooth with minute periclinal thickening at apex. Conidia inequilaterally fusiform or naviculate, hyaline, smooth, aseptate, guttulate, bearing mucoid apical appendages, flabelliform to irregular in shape. Sexual morph unknown (adapted from Crous et al. 2014b).

Culture characteristics: Colonies spreading, flat with sparse aerial mycelium and feathery margins. On PDA surface olivaceous grey, reverse iron-grey. On OA surface olivaceous grey with patches of iron-grey.

Optimal media and cultivation conditions: PNA at 25 °C under continuous near-ultraviolet light to promote sporulation.

Distribution: North America and Europe.

Hosts: Conifers (Pinaceae).

Disease symptoms: Canker and dieback

DNA barcodes (species): ITS, rpb2. Table 1.

Table 1. DNA barcodes of accepted Allantophomopsiella sp.

1 CBS: Westerdijk Fungal Biodiversity Institute, Utrecht, the Netherlands. ^ET indicates ex-epitype strain.2 ITS: internal transcribed spacers and intervening 5.8S nrDNA; rpb2: partial RNA polymerase II second largest subunit gene. 

Notes: This genus was recently introduced by Crous et al. (2014b) to accommodate A. pseudotsugae, a pathogen of conifers that was found to be very damaging, especially afterwounding during tree dormancy (Roll Hansen 1992). In a study considering the pathogenicity of this fungus on Pinus sylvestris associated with pruning wounds, it was observed that Allantophomopsis pseudotsugae occurred commonly in slash of pine trees wounded during the autumn (Uotila 1990).

Allantophomopsiella is morphologically related to the phytopathogenic genera Apostrasseria and Allantophomopsis. However, it can be easily differentiated from both genera by the lack of percurrent proliferation on its conidiogenous cells, and by the production of inequilaterally fusiform or naviculate conidia.

References: Uotila 1990 (pathogenicity); Crous et al. 2014b (morphology and phylogeny).

Allantophomopsiella pseudotsugae

(M. Wilson) Crous, IMA Fungus 5: 180. 2014.

Basionym: Phomopsis pseudotsugae M. Wilson, Transactions of the Royal Scottish Arboricultural Society 34: 147. 1920.

Synonyms: Phacidiella coniferarum G.G. Hahn, Mycologia 49: 227. 1957.

Phacidium coniferarum (G.G. Hahn) DiCosmo, et al., Canad. J. Bot. 61: 37. 1983.

Allantophomopsis pseudotsugae (M. Wilson) Nag Raj, Coelomycetous anamorphs with appendage-bearing conidia: 116. 1993.

Additional synonyms are provided in Nag Raj (1993.

Materials examined: UK, Scotland, Murthly, on Pseudotsuga menziesii (Pinaceae), Apr. 1920, M. Wilson (lectotype of Phomopsis pseudotsugae designated here: MBT379803, material deposited in Royal Botanic Garden Edinburgh, E00414771). Norway, Førde in Sunnfjord, shoot of Pseudotsuga menziesii (Pinaceae), Apr. 1948, H. Robak (epitype of Phomopsis pseudotsugae designated here CBS H-23354, MBT379804, culture ex-epitype CBS 320.53).

Notes: Allantophomopsis pseudotsugae was introduced by Wilson (1920) as Phomopsis pseudotsugae to accommodate a fungus that infects Pseudotsuga menziesii in Scotland. Type material was not specified when it was described, but the author deposited original material used for the Royal Botanic Garden Edinburgh. This material with the barcode number E00414771, which appears to be syntype material of the species, is selected here as lectotype. To fix the use of the name, the strain CBS 320.53 is designated here as ex-epitype. This strain was collected in Norway, occurring on the type host (Wilson 1920), and fits well with the description of the species recently provided by Crous et al. (2014b.

Authors: Y. Marin-Felix & P.W. Crous