Thirteen new species of Agromyzidae (Diptera) from the United States, with new host and distribution records for 32 additional species
Author
Eiseman, Charles S.
Author
Lonsdale, Owen
0000-0001-7034-3330
onsdale@agr.gc.ca
Author
Linden, John Van Der
0000-0003-2651-0634
johnbvdl@gmail.com
Author
Feldman, Tracy S.
0000-0001-5939-6810
feldmants@sa.edu
Author
Palmer, Michael W.
0000-0003-1452-2152
mike.palmer@okstate.edu
text
Zootaxa
2021
2021-02-17
4931
1
1
68
journal article
7424
10.11646/zootaxa.4931.1.1
d63cab47-63f1-4fdc-9209-26a256c91ccb
1175-5326
4545337
88CF2B0D-E02B-46E1-9F52-1B95F717FC8F
Melanagromyza gentianivora
Eiseman & Lonsdale
,
spec. nov.
(
Figs. 5–8
,
93–98
)
Holotype
.
USA
.
IOWA
:
Winneshiek Co.
,
Upper Iowa River Wildlife Management Area
,
29.xi.2017
, em. spring 2018,
J. van der Linden
, ex
Gentiana andrewsii
, #
CSE4647
,
CNC1144037
(1♁).
Paratypes
.
IOWA
:
Winneshiek Co.
,
i.2018
, em. spring 2018,
J. van der Linden
, ex
Gentiana andrewsii
, #
CSE4666
,
CNC1144033
(
1♀
); same collection as
holotype
,
CNC1144037
(
1♀
)
;
WISCONSIN
:
Grant Co.
,
Thomas Wet. Prairie, A.H
. Williams, stems of
Gentiana andrewsii
,
T7
N
R1
W Sect.
7, [host stem] stripped of inflorescences and leaves, put in sterile containers over sterile soil and netted with hosiery on
30.ix.1997
, outdoors until
2.iii.1998
, when tightly caged in lab, em.
12–14.iii.1998
,
CNC934513–934524
(3♁
7♀
,
WIRC
; 1♁
1♀
,
CNC
)
.
Etymology.
The specific epithet refers to the host plant genus,
Gentiana
Tourn. ex L.
Host.
Gentianaceae
:
Gentiana andrewsii
Griseb.
Larval biology.
The larva bores in the pith of the stem.
Puparium.
(
Fig. 8
) Pale brown, formed within the stem. Most puparia were found in the upper half or upper third of the stem.
Phenology and voltinism.
Pupae overwinter, with adults emerging within two weeks of exposure to warm temperatures in spring.
Distribution.
USA
: IA, WI.
Adult description.
Wing length
2.6 mm
(♁), 2.8–3.0 mm (
♀
). Length of ultimate section of vein M
4
divided by penultimate section: 0.7–0.9. Eye height divided by gena height: 4.6–5.7. First flagellomere small, rounded. Orbital plate and parafacial relatively pronounced, continuing as strong cheek under eye. Lunule high, extending to level of posterior ori, with shallow medial groove. Ocellar triangle reaching level of anterior ors. Facial ridge present, with broad sloping sides. Venter of gena relatively straight to modestly angled behind middle. Clypeus rounded with anterior margin somewhat straighter. Head longest above midpoint. Thorax subshining.
Chaetotaxy
: Three ori (sometimes two on one side), two or three ors (sometimes two on one side and three on the other), with ori and ors sometimes difficult to differentiate due to gradual change in orientation; setae long and overlapping, subequal to ocellar and postvertical setae, almost evenly spaced. Eye hairs subequal to orbital setulae in male, relatively dense dorsomedially; female eye hairs very short and inconspicuous, slightly denser dorsomedially, nearly extending to eye midpoint. Orbital setulae relatively short, in two to three scattered rows, orientation lateroclinate or reclinate to slightly erect. Two strong dorsocentral setae, second slightly more than ¾ length of first. Acrostichal setulae in ten rows. Two strong katepisternal setae. Mid tibia with two posteromedial setae (three in one male).
Coloration
: (
Figs. 5–7
) Setae dark brown. Color dark brown, including halter; abdomen with metallic green shine that is also present but less evident on thorax, and faintly visible on legs; wing veins brown. Calypter margin and hairs yellow.
Genitalia
: (
Figs. 93–98
) Epandrium with small distoventral spine. Surstylus shallow, wide and slightly round- ed, fused to anteroventral margin of epandrium, with cluster of tubercle-like setae along distal margin. Hypandrium very broad and rounded basally, contrasting long apical apodeme; inner lobe arched, setose. Phallophorus narrow with base constricted, venter strongly bulging. Basiphallus U-shaped with base almost straight; slightly overlapping mesophallus. Mesophallus cylindrical, slightly curved, ventromedially fused to distiphallus; base slightly exceeding that of distiphallus. Distiphallus with basal third consisting of paired tubules flanking mesophallus; remainder very narrow in ventral view, with one pair of dark swollen pads past mesophallus followed by one pair of lateral wingshaped, internally spinulose extensions beneath a long, narrow distal process; laterally compressed dorsal chamber evident in lateral view. Ejaculatory apodeme large, dark, well-developed; base narrow, stem with lateromedial process; sperm pump with dark transverse bar upcurved at ends.
Comments.
The only previous record of a North American agromyzid from
Gentiana
refers to this species; the specimens of an undetermined
Melanagromyza
that
Williams (1999)
reared from overwintering stems of
Gentiana andrewsii
in Wisconsin are included here as
paratypes
. The only other
Agromyzinae
species known from the host family
Gentianaceae
is
Ophiomyia akbari
(Singh & Ipe)
, a leafminer of
Enicostema verticillatum
(L.) Engl. in
India
(
Singh & Ipe 1971
).
Melanagromyza gentianivora
is a relatively large, greenish species with a slightly projecting orbit (less so than the strongly pronounced state seen in
M. arnoglossi
). Depending on how pronounced the orbit is interpreted to be, this species will key either to
M. cirsiophila
Spencer
or
M. longensis
Spencer
in
Spencer & Steyskal (1986)
, but the first species has the gena deepest medially (not posteriorly), and the second has a shallower orbit, fewer rows of acrostical setulae and a shining ocellar triangle and orbital plate. Both of these other species also have only two ors and an unmistakably different phallus. The unusual distiphallus of
M. gentianivora
sets it far apart from all congeners, and its closest relative cannot be confidently guessed at present.