Juglanconis Voglmayr & Jaklitsch, in Voglmayr, Castlebury & Jaklitsch, Persoonia 38: 142 (2017)
Diaporthomycetidae, Diaporthales, Juglanconidaceae, Juglanconis
Saprobic on dead corticated twigs and branches of Juglandaceae attached to trees. Sexual morph: Pseudostromata comprising an inconspicuous ectostromatic disc which are erumpent from bark. Central column beneath the disc, nearly conical. Perithecia surrounding the central column, with nearly globose base, with long lateral ostioles that emerge at the margin or within an ectostromatic disc. Asci 8-spored, clavate to fusoid, with a J-, apical ring. Ascospores overlapping 1–2-seriate, hyaline, broadly fusiform, bicelled, slightly curved, guttulate, with or without gelatinous appendages. Asexual morph: Coelomycetous. Conidiomata acervular, with ectostromatic disc and conical central column. Conidiophores aseptate or septate, smooth, hyaline to brownish, occasionally branched. Conidiogenous cells annellidic. Conidia initially hyaline, becoming brown with age, various in shape, pip-shaped, narrowly ellipsoid, elongate to suballantoid, unicellular, often truncate with scar at the base, with gelatinous sheath and irregular verrucae on the inner surface of the conidial wall (adapted from Voglmayr et al. 2017).
Type species: Juglanconis juglandina (Kunze) Voglmayr & Jaklitsch, in Voglmayr, Castlebury & Jaklitsch, Persoonia 38: 144 (2017)
Notes: Juglanconis was established by Voglmayr et al. (2017) to accommodate three combined species including J. juglandina (WU 35965, neotype), J. oblonga (MBT374386, lectotype), J. pterocaryae (TFM FPH2623, holotype) and a newly introduced species J. appendiculata (WU 35954, holotype). These species were previously placed in Melanconium but they are morphologically different from Melanconium sensu stricto in having irregular ornamentation on the inner surface of the conidial wall (Voglmayr et al. 2017). Fresh collections and updated morphological descriptions of Juglanconis juglandina and J. oblonga collected from Juglans regia in China were also provided by Fan et al. (2018). Subsequently, two new species Juglanconis japonica occurring on Pterocarya rhoifolia and J. pterocaryae occurring on Pterocarya fraxinifolia were introduced to this genus (Voglmayr et al. 2019b). To date, five species are accepted in Juglanconis and more fresh collections are needed (Voglmayr et al. 2019b). Currently Juglanconis species have calM, histone, ITS, LSU, ms204, rpb1, rpb2, tef1 and tub2 gene sequence data available for multilocus analyses (Voglmayr et al. 2019b).
All species of Juglanconishave been reported on Juglandaceae (walnut family), such as Juglans ailanthifolia, J.cinerea, J.nigra, J.regiaand Pterocarya rhoifolia. Juglanconisspecies have a wide distribution across Austria, China, the Czech Republic, France, Germany, Greece, Japan, Russia, Spain and the USA (Fan et al. 2018). Juglanconis juglandinaand J.oblonga were regarded as the main causal agent of canker and dieback disease of Juglans regia in China (Fan et al. 2018).