The New World species of Cerodontha (Xenophytomyza) Frey (Diptera: Agromyzidae)
Author
Boucher, Stéphanie
text
Zootaxa
2003
178
1
8
journal article
10.5281/zenodo.157066
bddce942-feff-4dfb-be09-c1e682bcc4e9
11755326
157066
Cerodontha (Xenophytomyza) illinoensis
(Malloch)
(Figs. 4–6, 8)
Agromyza illinoensis
Malloch, 1934
: 483
.
Cerodontha (Xenophytomyza) illinoensis:
Frick 1952
: 151
.
Cerodontha (Poemyza) simcoensis
Spencer, 1969
: 135
.
Recognition.
Cerodontha (Xenophytomyza) illinoensis
is externally very similar to
C. (X.) biseta
. Following Malloch’s (1934) brief original description, this species was redescribed and/or illustrated by
Frick (1952)
and
Spencer and Steyskal (1986)
.
Spencer (1969)
described
Cerodontha (Poemyza) simcoensis
from Ontario but later synonymized it with
C. (X.) illinoensis
(
Spencer & Steyskal 1986
)
.
Frick (1952)
distinguished
C. (X.) illinoensis
from
C. (X.) biseta
by the paler coloration, the third antennal segment having a more pronounced angle and the genovertical plates raised above the eye margins, but these characters are not consistent among the specimens examined and could not be used in the key.
Distribution.
Cerodontha (X.) illinoensis
is so far restricted to the northeastern Nearctic region. It appears that this species is not as commonly collected as
C. (X.) biseta
in North
America
; it is known from only four localities (
Fig. 8
) and, apparently, no confirmed specimens have been collected since 1952.
Host plants. The host plant of
C. (X.) illinoensis
is unknown but, given the known host plants of other species of the subgenus, it is probably in the
Poaceae
.
Remarks. Malloch’s original description of
Agromyza illinoensis
was a brief mention in the introduction to a paper on Neotropical
Agromyzidae (
Malloch 1934
)
, but he included enough characters to distinguish it from other North American species and thus his description was valid (
Frick 1952
). Although Malloch did not record any
type
material in his publication, he had labeled one specimen in the INHS as “
type
” and two others in the NMNH as
paratypes
(
Frick 1952
). Frick considered the specimen labeled “
type
” to be the
holotype
, and the other two labeled specimens as well as eight other specimens collected at the same locality in the same month to be
paratypes
.
Frick (1952)
designated the “
type
” specimen as a
neotype
(this may have been an error for “
lectotype
”) and designated Malloch’s two labeled
paratypes
and the eight additional
paratypes
as “neoallotype” and “neoparatypes”. However, according to the International Code of Zoological Nomenclature (ICZN 1999) Malloch’s original description did not explicitly designate
type
specimens and the description was apparently based on multiple specimens, so all of Malloch’s specimens should be considered
syntypes
(ICZN Article 73.1, Recommendation 74F) and Frick’s (1952) designation of a
neotype
was invalid because the
syntype
series was still in existence (ICZN Article 75.1). Because the identity of this species is not in doubt, I have chosen not to designate a
lectotype
.
Type
material (
Cerodontha illinoensis
).
Syntypes
:
UNITED STATES
: Illinois:
White Heath,
22.v.1915
(3F); same except
8.v.1915
(1M, 1F), same except
9.v.1915
(2M), same except
16.v.1915
(2F), same except
30.v.1915
(2F) (INHS, NMNH).
Type
material (
Cerodontha simcoensis
).
Holotype
M:
CANADA
: Ontario:
Simcoe,
9.vi.1939
, G.E. Shewell (CNC).
Paratypes
: same data as
holotype
(2M, 1F, CNC) (two other female
paratypes
are not conspecific).
Other material.
UNITED STATES
: Illinois:
White Heath,
2.vi.1917
(2M, 2F, INHS)
3.vi.1917
(4M, 4F, INHS);
Tennessee:
East Ridge, Hamilton Co.
5.v.1952
, G. Peck (2M, CNC, not examined);
Virginia:
Maywood, Alexandria Co,
4.vi.1922
(2M, 1F, NMNH).