Leaf-inhabiting genera of the Gnomoniaceae, Diaporthales - CBS

So g o n o v e t a l.
Table 2. Characteristics of genera in the Gnomoniaceae.
Habit of
perithecia
Stroma
Perithecia
Ascospores
Colony
growth rate
Conidiomata
formation in
culture
Host
Gnomonia
Single on leaves of trees
and shrubs.
Without stroma. Some
species with collar
around neck.
Erumpent, concave
when dry; or remaining
immersed but then with
very short necks or with
collar around neck.
One median or supramedian
septum, rarely
non-septate; ellipsoidal
to fusiform or acerose,
appendages short or
long.
Without stroma.
With collar
around neck.
One median
septum, fusiform,
appendages
medium.
Without stroma
or with weak
stroma if on
twigs.
One septum,
variable from
submedian,
median to
supramedian,
ellipsoidal, appendages
absent
or present.
Cryptosporella
In groups on twigs.
Ambarignomonia
Single on leaves
of trees and
shrubs.
Apiognomonia
Single on leaves
of trees and
shrubs and on
herbaceous
plants. In groups
on twigs.
Gnomoniopsis
Single on
leaves of trees
and shrubs.
Single or in
groups on herbaceous
plants
or on twigs.
Ophiognomonia
Single on leaves of
trees and shrubs and
on herbaceous plants.
Plagiostoma
Single on leaves
of trees and
shrubs and on
herbaceous
plants. In groups
on twigs.
With weak stroma. Without stroma. Without stroma. Without stroma or
with weak stroma
if on twigs.
Perithecia remaining immersed, convex when dry.
Two species may
have some irregularly
shrunk or concave
perithecia when dry,
partly erumpent.
Usually non-septate,
rarely with one
median septum,
ellipsoidal, fusiform,
femoroid to vermiculate.
One submedian
or median septum,
ellipsoidal,
slightly broader
in their upper
part with no
apendages.
One median septum,
rarely submedian,
supramedian in filiform
ascospores, or absent,
ellipsoidal or fusiform
(acerose), rarely
filiform, appendages
short or long but not
stout.
Slow–moderate. Slow. Fast. Slow–moderate. Moderate–fast. Moderate–fast. Fast.
Rarely. Never. Often, sometimes
abundant.
Strictly family Betulaceae,
mostly subfamily
Coryloideae.
Known only from
Liquidambar
styraciflua
(Hamamelidaceae).
Diverse
taxonomic
groups (mostly
Aceraceae,
Fagaceae,
Geraniaceae,
Platanaceae,
occasionally
Anacardiaceae,
Hippocastanaceae,
Juglandaceae,
Onagraceae,
Rosaceae,
Tiliaceae).
In some species
none, in some
abundant.
Betulaceae, Tiliaceae,
Ulmaceae.
Usually abundant.
Diverse taxonomic
groups
(Ericaceae,
Fagaceae,
Rosaceae,
Tiliaceae).
Rarely.
Mostly Fagales (Betulaceae,
Fagaceae,
Juglandaceae), a few
species on Lauraceae,
Rosaceae, Salicaceae,
Tiliaceae.
One median
septum, rarely
submedian or absent,
ellipsoidal,
appendages absent
or present.
Often, sometimes
abundant.
Diverse
taxonomic groups
(Aceraceae,
Euphorbiaceae,
Geraniaceae,
Hippocastanaceae,
Oleaceae,
Polygonaceae,
Salicaceae,
Staphyleaceae).
short to long appendages. The colonies in culture grow at a slow to
moderate rate and rarely form conidiomata in culture. Similar to the
stromatic Cryptosporella, the genus Gnomonia occurs primarily on
members of the Betulaceae.
The genus Ambarignomonia is established for the distinctive
species, A. petiolorum, that is common on Liquidambar styraciflua
(Hamamelidaceae), native to North America. Easy to recognise
because of the white collar around the relatively long neck of the
perithecia, Ambarignomonia is otherwise similar to members of
the Gnomoniaceae in their occurrence on fallen leaves, lack of
stromatic development, and perithecia that remain immersed in the
substrate and collapse from the top when dry. The ascospores are
fusiform, have one median septum, and bear appendages at both
ends. The colonies are relatively slow-growing and do not produce
conidiomata in cultures. In all analyses A. petiolorum appears to be
unique among species in the Gnomoniaceae.
The type species of Apiognomonia, A. veneta, and a second
species, A. errabunda, were redescribed by Sogonov et al. (2007).
In the present work three additional species have been determined
to be congeneric with these species including A. hystrix, on woody
substrates. Apiognomonia includes species producing solitary
perithecia without a stroma or with a weakly developed stroma
on decaying leaves and twigs. The perithecia remain immersed
and become convex or collapse from the base when dry. The
ascospores have one septum that is variable in placement ranging
from median to supramedian. They are ellipsoidal with or without
appendages. In culture species of Apiognomonia are relatively
fast-growing and often produce abundant conidiomata. Species of
Apiognomonia occur on a wide variety of woody plant hosts in the
Aceraceae, Fagaceae, and Plantanaceae as well as herbaceous
families such as the Anacardiaceae, Geraniaceae, Onagraceae,
and Rosaceae.
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