Leaf-inhabiting genera of the Gnomoniaceae, Diaporthales - CBS

So g o n o v e t a l.
Holotype: U.S.A., Washington, Mason Co., Potlatch State Park,
next to U.S. route 101, on overwintered fallen leaves, 16 May
2006, M.V. Sogonov MS0364a (BPI 877465B, ex-type culture CBS
121245).
Additional specimen examined: U.S.A., Washington, King Co., Tiger Mountain State
Forest, near U.S. route 18, 16 May 2006, M.V. Sogonov MS0393 (BPI 877535,
culture CBS 121398) GenBank EU254798.
Notes: This new taxon is similar to Gnomonia californica described
by Monod (1983) as compared with the description and illustrations
only. According to Monod the type specimen of G. californica is
deposited in TRTC from where it was requested but was not found.
Gnomonia skokomishica lacks a dark red collar as described for
G. californica by Monod (1983) as “collum rubrum rostrum cingens
ex substrato”, “le substrat forme une couronne rougeâtre, non
pulvérulente à la sortie du bec”. In addition G. skokomishica has
a submedian ascospore septum while G. californica is described
as having a median septum (“ascosporae… septatae dimidio
longitudinis”, “ascospores… cloisonnées à mi-longueur”) (Monod
1983).
Gnomonia virginianae Sogonov, sp. nov. MycoBank MB 512168.
Figs 12A–C; 13A–C; 14A–F.
Perithecia 115–160 µm high × 150–260 µm diam. Rostrum 200–
430 µm longum, basi 21–33 µm diam, apice 18–28 µm diam.
Ascosporae fusiformes, leviter curvatae, (12–)13–14(–14.5) × (2–)
2.5–3 µm, L:l (4–)4.5–5(–6). Ad plerumque cum rostro eccentrico
Gnomoniae speciebus ascosporae longitudine latitudineque differt.
Ascosporae longitudo latitudoque similares G. romanii, sed septi
positione et hospitis genere differt. Holotypus: BPI 844264.
Anamorph: Unknown.
Etymology: Refers to species epithet of the host plant.
Perithecia hypophyllous, on leaf blade or veins, in loose irregular
groups, immersed at first, erumpent later, black, suboblate to oblate
spheroidal when moist, 115–160 µm high × 150–260 µm diam,
concave when dry. Necks marginal, straight or slightly sinuous,
200–430 µm long, 21–33 µm wide at base, 18–28 µm wide at apex.
Asci fusiform with narrow tapering stipe, (33–)34.5–42(–47.5) ×
(8–)9.5–11(–14) µm (mean = 38.5 × 10.5, SD 5, 1.5, n=14) , apical
ring 2–2.5 µm diam, with eight ascospores arranged unevenly
parallel, less commonly in evenly parallel or irregularly multiseriate.
Ascospores fusiform, slightly curved (12–)13–14(–14.5) × (2–)2.5–
3 µm (mean = 13.5 × 2.5, SD 0.5, 0.2, n=47), l:w (4.2–)4.7–5.3(–
5.8) (mean = 5, SD 0.4), two-celled, slightly constricted at septum,
septum located at (55–)59–62(–66) % (mean = 61.5, SD 3) of
ascospore length, cells tapering, at ends blunt, rounded, distal cell
usually with two, basal cell with two or three large guttules, several
smaller guttules may be present in each cell; appendages whipshaped,
7–45 µm long.
Cultures: Colonies on PDA attaining 30 mm diam after 40 d at
23 °C, with knobbed surface, velvety, greyish orange, brownish
orange, pale brown or brownish grey, with droplets of clear exudate;
margin well-defined, irregular; reverse pale brown to dark brown.
Colonies on MEA attaining 30 mm diam after 40 d at 23 °C, radially
wrinkled and furrowed, velvety, orange-grey to brownish orange;
margins with two brims differing from the rest of colony, 1–2 mm
wide each, a dark brown velvety inner brim and greyish orange
waxy outer brim; margin well-defined, even; reverse greyish orange
and orange-grey to brownish orange and brown. Colonies on MYA
attaining 22 mm diam after 40 d at 23 °C, densely radially wrinkled,
velvety to felty, orange-white with pale brown 3 mm brim; margin
well-defined, even; reverse greyish brown to pale brown. Neither
perithecia nor conidiomata observed in cultures on PDA, MEA and
MYA after 8 mo at 2/10 C. Scarce fertile perithecia were observed
in cultures on CMA after 5 mo at 15 °C in darkness.
Habitat: On overwintered fallen leaves of Ostrya virginiana
(Betulaceae).
Distribution: U.S.A. (AR, GA, MD, NC).
Holotype: U.S.A., Maryland, Montgomery Co., Chesapeake & Ohio
Canal National Historic Park, 10 April 2004, M.V. Sogonov MS0016
(BPI 844264, ex type culture CBS 121913).
Additional specimens examined: U.S.A., Arkansas, Ozark Natural Science Center, 21
June 2006, L.N. Vasilyeva (BPI 877565A) GenBank EU254804; Georgia, Clarke Co.,
Athens, Oconee Forest Park, 30 March 2007, M.V. Sogonov MS0532 (BPI 878209)
GenBank EU254805; Georgia, Clarke Co., Athens, Botanical Garden, Orange Trail,
28 March 2007, M.V. Sogonov MS0534 (BPI 878210); Maryland, Mongomery Co.,
Chesapeake & Ohio Canal National Historic Park, 10 April 2004, M.V. Sogonov
MS0023 (BPI 877564) GenBank EU254802; North Carolina, Wake Co., Raleigh,
William B. Umstead State Park, hardwood forest, 03 April 2005, M.V. Sogonov MS0169
(BPI 877566) GenBank EU254803; same collecting data MS0170 (BPI 877422).
Notes: Gnomonia virginianae is the only species of Gnomonia
on Ostrya in North America and is distinct from the two European
species on Ostrya, G. arnestadtiensis and G. ostryae. Gnomonia
arnstadtiensis has perithecia lacking an elongated neck while
ascospores of G. ostryae are longer and wider than those of G.
virginianae. Many specimens of Gnomonia virginianae were
identified as Apiognomonia ostryae variété 2 by Monod (1983).
Additional species accepted in Gnomonia
Gnomonia amoena (Nees : Fr.) Ces. & De Not., Comment. Soc.
Crittog. Ital. 1: 232. 1863.
Figs 12D–F; 13D,E; 14G–L.
≡ Sphaeria amoena Nees : Fr., Nova Acta Acad. Caes. Leop.-Carol. Nat.
Cur. 9: 257. 1818 : Syst. Mycol. 2: 517. 1823.
≡ Gnomoniella amoena (Nees : Fr.) Sacc., Syll. Fung. 1: 414. 1882.
Habitat: On dead leaves and petioles of Carpinus betulus and C.
caroliniana (Betulaceae).
Distribution: Europe (Germany, Switzerland) and U.S.A. (TN).
Specimens examined: Switzerland, Lausanne, on overwintered leaves of Carpinus
betulus, 25 May 2005, coll. M.V. Sogonov (BPI 877468) GenBank EU254770; Vaud,
near hospital St-Loup, on overwintered leaves of Carpinus betulus, 24 May 2005,
EU254769.
Notes: Gnomonia amoena is unique among species of Gnomonia
on Carpinus in having a distinct collar around the central neck.
Monod (1983) provides a detailed description of this species.
Barr (1978) erred in reporting this species on Corylus based on
specimens later identified by Monod (1983) as G. californica M.
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