Revision of the Soft-Winged Flower Beetles of the Genus Asydates Casey, 1895 (Coleoptera: Melyridae: Dasytinae: Listrini)
Author
Mayor, Adriean J.
Author
Gimmel, Matthew L.
text
The Coleopterists Bulletin
2019
mo 17
2019-12-19
73
1
71
http://dx.doi.org/10.1649/0010-065x-73.mo17.1
journal article
10.1649/0010-065X-73.mo17.1
1938-4394
4906665
3B2B38A0-F732-4356-9A4A-E306C0C91EE1
6.
Asydates irwini
(
Howell, 1979
)
,
new combination
(
Figs. 3C–D
,
8C–D
, 11E–F, 15E–F, 18A, 22A, 23C, 24E, 28F, 34B, 35C, 37B, 39, 43)
Pristocelis
[
sic
]
irwini
Howell 1979: 41–43
, 45, fig. 1.
Neotype
, male, from “Deep Canyon”, CAS type #17130, herein designated.
Howell 1997: 13
;
Mawdsley 2003: 155
.
Scelopristis irwini
: Mayor 2004: 86
.
Type Material.
Neotype
♂
(
Fig. 43
), deposited in
CAS
, labeled, “
Deep Canyon
\
Riv. Co.
Cal
\
x-13 1963
[white printed and hand written label] //
M. E. Irwin
\Collector [white printed label] //Collected on\
Stephanomeria
\pauciflora [white printed and hand written label] //Pogonomyrmex californicus \with captured \
Pristoscelis
[white hand written label] //
Neotype
\irwini \Det. by
C. D. Howell
[red hand written label] //
California
Academy \of Sciences \Type No. 17130 [white printed and hand written label] //
NEOTYPE
\
Pristoscelis
\
irwini
Howell
\des. Mayor &
Gimmel 2019
[red printed label]”.
The original
holotype
of
P. irwini
was apparently lost, and Howell designated an unpublished “
neotype
”. The following note was found in the
A. irwini
unit tray in the
UCRC
collection: “1980: Original
Holotype
was lost at UCR. A substitute
Holotype
was sent to Cal. Acad. 1993” [white printed label]; on the reverse, “This note was typed by C. D. Howell” [handwritten by Saul Frommer]. In the
CAS
collection, there is a male specimen with the label “
Neotype
,
irwini, Det.
by C. D. Howell” [red handwritten label]. However, this
neotype
designation was never published. In this study, we accept this specimen as
neotype
with the following added label: “
NEOTYPE
Pristoscelis irwini
Howell
, des. Mayor &
Gimmel 2019
” [red printed label] and consider the
neotype
, a male, herein designated. This designation is being made to avoid confusion with the closely related
A. shoshone
, with which it might be confused.
Diagnosis.
The robust body, frons with an arched ridge behind epistomal suture, and dense comb of stout black spines along the margin of the pro- and mesotibiae of both sexes distinguish
A
.
irwini
from all other species of
Asydates
.
Redescription.
Body broad, robust, shiny (
Figs. 3C–D
,
8C–D
); microsculpture sparse, inconspicuous on head, pronotum, and elytra. Length
2.7 mm
(2.1–3.0 mm,
n
= 20); width
1.2 mm
(
0.9–1.4 mm
,
n
= 20). Head, pronotum, and venter black; elytra orange to orange brown with a V-shaped, black macula variable in extent; legs in both sexes and female ventrites 2–5 more or less orange, antennomeres darker, reddish brown. Pubescence dense, reclining, pale, whitish, occasionally golden; pronotal and elytral fringe short, dense. Punctation with punctures fine, indistinct on head and pronotum, slightly larger, more distinct on elytra.
Head:
Large, narrower than pronotum in both sexes, eyes bulging (Fig. 11E–F); male head 1.37 (1.28–1.47,
n
= 10), female head 1.49 (1.44–1.53,
n
= 10) times wider than interocular distance; male head with occipitotemporal region behind eye elongate; male frons with a distinct arched ridge behind epistomal suture. Antennomeres 5–10 weakly serrate; male antennae short, reaching to near middle of pronotum posteriorly, female antennae shorter.
Thorax:
Pronotum short, wide, 0.69 (0.67–0.73,
n
= 20) times as long as wide; widest at middle; lateral edges converging to anterior margin, slightly constricted before anterior margin; anterior and posterior angles obsolete, broadly rounded (
Fig. 15E–F
). Elytra elongate, broadly oval, elytron 3.41 (2.91–4.00,
n
= 20) times as long as wide, at humeri slightly wider than pronotum; elytral epipleuron distinct at base, becoming obsolete near apex of abdominal ventrite
4 in
both sexes; apical margin broadly rounded to sutural angle, inconspicuously serrulate in both sexes. All tibiae with fine, white setae along external margin; pro- and mesotibiae with dense comb of short, stout, black spines arranged along external margin in both sexes (
Fig. 18A
).
Abdomen:
Male ventrite 1 with indistinct median patch of whitish setae. Pygidium unmodified, apex broadly rounded in both sexes (
Fig. 22A
); spiculum gastrale as in
Fig. 23C
. Median lobe of aedeagus a bowed tube with apex bent slightly ventrally (
Fig. 24E
); tegmen very short and wide, without constriction at base of ring (
Fig. 28F
).
Host Plant Associations.
Adults of
A
.
irwini
have been collected from flowers of plants in the families
Asteraceae
[
Isocoma acradenia
(1),
Palafoxia linearis
(3),
Stephanomeria pauciflora
(203) (
Figs. 34B
,
35C
), and
Stephanomeria
sp.
(1)],
Polygonaceae
[
Eriogonum
sp.
(2)], and
Zygophyllaceae
[
Larrea tridentata
(4)].
Seasonal Distribution.
25 August to 7 December (
Fig. 39
).
Geographic Distribution.
Deserts and desert margins of
Kern County
south to
Imperial County
,
California
, east to northwestern
Arizona
and southwestern
Utah
(
Fig. 37B
)
.
Material Examined.
Records
reported here are based on the examination of
255 specimens
.
USA
:
ARIZONA
:
Mohave County
:
Virgin River Canyon Recreation Area
, 23
September
, 1986,
Baumann
&
Nelson
(
1♂
,
2♀♀
,
BYU
,
1♂
,
1♀
,
UCRC
).
CALIFORNIA
:
Imperial County
:
12 miles
So. of Ocotillo
,
on
Stephanomeria pauciflora
/
Timberlake Coll.
,
Nov.
12 ‘39 (
1♀
,
UCRC
)
;
Kern County
:
7.5 mi.
S.
Inyokern on Co. Rd.
,
5- x-1985
,
G. H. Nelson
, on yellow composite (
1♀
,
UCRC
)
;
Oak Creek Rd.
, W. of
Mojave
, elev.
1,170 m
,
N35°03’05.9”
,
W118°19’47.2”
,
1 Sept. 2016
,
A. J. Mayor
, collected beating flowers of
Stephanomeria pauciflora
(
15♂♂
,
9♀♀
,
UCRC
,
1♂
,
1♀
,
SBMNH
)
;
Los Angeles County
:
Bob’
s
Gap Rd.
, W. of
Bob’
s
Gap
;
elev.
1182 m
,
N34°26’57.2”
,
W117°49’52.3”
,
7 Sept. 2016
, A. J.
Mayor
, collected beating flowers of
Stephanomeria pauciflora
(
10♂♂
,
16♀♀
,
UCRC
,
1♂
,
1♀
,
SBMNH
)
;
4 mi.
N. Lancaster
,
ix-9-1962
,
John
T.
Doyen
(
3♂♂
,
1♀
,
EMEC
)
;
Pallett Creek Rd.
W. of
Big Rock Creek
, elev.
1,087 m
,
N34°27’33.9”
,
W117°52’12.6”
,
7 Sept. 2016
,
A. J. Mayor
, collected beating flowers of
Stephanomeria pauciflora
(
20♂♂
,
19♀♀
,
UCRC
)
.
Riverside County
:
Coyote Creek
,
x-15-1963
,
M. E. Irwin Collector
(
7♂♂
,
9♀♀
,
UCRC
)
;
same except
Stephanomeria
(
1♀
,
UCRC
)
;
same except
Palafoxia linearis
(
1♂
,
UCRC
)
;
Coyote Creek
Basin,
x-15-1963
,
M. E. Irwin
collector, collected
on
Palafoxia linearis
(
1♂
,
1♀
,
UCRC
)
;
Deep Canyon
,
x-13-1963
,
M. E. Irwin
collector, on
Hiptus
[sic] twig, +/-
60 ft.
from host plant (
1♂
,
UCRC
)
;
same except
xi-12- 1963
,
M. E. Irwin
collector,
on
Stephanomeria pauciflora
(
3♂♂
,
2♀♀
,
UCRC
)
;
same except
x-15-1963
(
3♀♀
,
UCRC
)
;
Deep Cyn.
, ix-10-64,
E. I. Schlinger
(
1♂
,
1♀
,
UCRC
)
;
4 miles
west Desert Center
,
Sp.
16, ’61,
on
Stephanomeria pauciflora
, Timberlake Coll.
(
1♀
,
UCRC
)
,
Pleasant Valley
,
x- 29-1963
,
E. I. Schlinger
collector,
on
Stephanomeria
sp.
(
1♀
,
UCRC
)
;
P. L. Boyd Desert Research Center
,
3.5 mi.
S. Palm Desert
,
9 Oct. 1963
,
Schlinger
,
Irwin
(
4♂♂
,
2♀♀
,
UCRC
)
;
same except 17-xii-63, M. E.
Irwin
(
1♂
,
UCRC
)
;
same except
x-13-1969
, no collector (
1♂
,
UCRC
)
;
same except 30-xi-63, M. E.
Irwin
,
on
Stephanomeria pauciflora
(
3♂♂
,
1♀
,
UCRC
)
;
same except
Coyote Creek
, 15-x-63,
E. I. Schlinger
,
on
Eriogonum
(
2♀♀
,
UCRC
)
;
same except
S. Palm Desert
,
Coyote Creek
,
15 x-1963
,
M. Irwin
(
1♂
,
1♀
,
UCRC
)
;
same except S.
Palm Desert
, 9-x-63, coll.
Schlinger
,
Irwin
,
on
Stephanomeria pauciflora
(
1♂
,
1♀
,
UCRC
)
;
Whitewater Canyon
, S. of
Whitewater Preserve
, elev.
561 m
,
N33°57’35.5”
,
W116°38’56.4”
,
28 August 2016
,
A. J. Mayor
, collected beating flowers of
Stephanomeria pauciflora
(
12♂♂
,
16♀♀
,
UCRC
,
1♂
,
1♀
,
SBMNH
)
;
San Bernardino County
:
Kelbaker Rd
nr
Granite Mts
overlook, 34.80521° -115.61078°,
1,210 m
,
5 October 2018
, ex
Stephanomeria pauciflora
,
M. & L. Gimmel
, ML308 (
1♂
,
1♀
,
SBMNH
)
;
Oro Grande
,
Sp.
14 ’35,
on
Isocoma acradenia
, Timberlake Coll.
(
1♂
,
UCRC
)
;
San Bernardino Natl. Forest
,
Hwy.
18, S. of
Lucerne Valley
, elev.
1,430 m
,
N34°20’56.4”
,
W116°50’44.9”
,
25 August 2016
,
A. J. Mayor
, collected beating flowers of
Stephanomeria pauciflora
(
16♂♂
,
16♀♀
,
UCRC
,
1♂
,
1♀
,
SBMNH
)
;
S. of
Lucerne Valley on Hwy.
18, elev.
1,392 m
,
N34°20’58.9”
,
W116°50’45.1”
,
24 August 2018
,
A. J. Mayor
, collected beating flowers of
Stephanomeria pauciflora
(
22♂♂
,
6♀♀
,
UCRC
)
.
UTAH
:
Washington
County
:
Beaver Dam Well
,
28 September 1985
,
on
Larrea
,
Nelson
&
Mower
(
3♂♂
,
1♀
,
BYU
)
;
3 miles
southwest of
Shivwits Indian Reservation
,
9 September 1959
,
Andrew
H.
Barnum
(
2♂♂
,
1♀
,
BYU
)
;
3 miles
south of
Welcome Spring
, 37°03.6’N, 113°55.2’W,
23 September 2011
,
S.M. Clark
(
1♂
,
2♀♀
,
BYU
,
1♂
,
1♀
,
UCRC
)
.
Remarks.
The elytral color is variable in
A. irwini
. The dark, V-shaped marking on the elytra varies from restricted to the basal quarter or less, leaving most of the elytra orange, to so extensive as to leave only the margins and apex of the elytra orange. This color variation does not appear to be sex linked or to have a geographic component.
The arched ridge on the frons behind the epistomal suture is the “frontal cord” of
Howell (1979
, fig. 1C). This unique structure of the frons is also found in males of
A. shoshone
in which it is less well developed.