Systematics of Robustagramma, a new genus of New World Sphaeroceridae (Diptera)
Author
Marshall, Stephen A.
Author
Cui, Yongsheng
text
Zootaxa
2005
2005-07-29
1026
1
1
122
https://biotaxa.org/Zootaxa/article/view/zootaxa.1026.1.1
journal article
10.11646/zootaxa.1026.1.1
11755334
5049813
3EDC6787-C73B-4969-BA06-022D0532364F
Robustagramma obscuratum
Cui and Marshall
,
new species
(
Figs. 74–80
)
As described for
Robustagramma binitidum
except as follows.
Body length 1.0–
1.6 mm
. Interfrontal bristles in 3 (rarely in 2) pairs. Postvertical bristles convergent,
ca
. 3/5 as long as inner occipital. Postocellar bristles absent. Eye height
ca
. 2.8–3.6 times genal height.
Dorsocentral bristles in 2 postsutural pairs, anterior dorsocentral bristles slightly shorter than prescutellar acrostichal bristles. Acrostichal setulae in 6–8 irregular rows between anterior dorsocentral bristles. Posterodorsal katepisternal bristle over half as long as distance between bristle base and wing base; anterodorsal katepisternal bristle small, slightly longer than half of posterodorsal. Wing with length ratio of second to third costal sector
ca
. 0.48–0.58. Mid femur of male with 4–6 ventral proximal bristles.
FIGURES 74–80.
Robustagramma obscuratum
sp. nov.
: 74, posterior view of male terminalia; 75, lateral view of male terminalia; 76, lateral view of male internal genitalia; 77, male sternite 5; 78, dorsal view of female terminalia; 79, ventral view of female terminalia; 80, spermathecae.
Male terminalia: Sternite 5
ca
. 1.5 times as long as sternite 4, obscure (without shining patches), with many clublike scales on posteromedial margin, a distinct borderline between dark anterior and pale posteromedial area, and a central patch of short, stout bristles. Dorsomedial length of ependrium
ca
. 0.3X length of sternite 8. Surstylus setose except for almost bare anteroventral lobe. Postgonite pointed apically. Ejaculatory apodeme small.
Female terminalia: Tergite10 with two small bristles and a posteromedial patch of small setulae. Cerci short, setose. Sternite 7 longer than sternite 6, rounded posteriorly. Sternite 8 absent. Sternite10 short, setulose. Spermathecae with distal portions shorter than basal portions. Paired spermathecae with ducts
ca
. 3 times as long as spermathecae.
Holotype
(
♂
,
DEBU
) and
paratypes
(
13 ♂
,
11 ♀
,
DEBU
):
BELIZE
:
San Ignacio
,
Maya
Mountain
Lodge
,
dung trap
,
7–8.i.1991
,
S.A. Marshall.
Other
paratypes
:
BELIZE
:
San
Ignacio, Maya Mountain lodge, sweep, second growth forest,
2.i.1991
(
2 ♀
,
DEBU
)
;
malaise,
7.i.1991
(
1 ♂
,
DEBU
)
;
sweep trail (
2 ♂
,
DEBU
)
,
malaise forest edge (
1 ♂
,
DEBU
)
,
19.i.1991
, S.A.
Marshall. Mountain
Pine Ridge, Hidden
Valley Inst.
,
2500ft.
, grasspine,
dung traps
,
10–15.i.1991
,
S.A. Marshall
(
1 ♀
,
DEBU
)
.
COLUMBIA:
Valle
,
RF
Bosque de Yotoco
, dung of “
Alovata seniculos”
,
16.xi.1997
,
C.A. Medina
(
1 ♂
,
2 ♀
,
DEBU
)
.
COSTA RICA
:
Alajuela
,
Volcán Tenorio, N
slope nr.
Bijagua Biol. Stn.
,
700m
, sweep over
Atta
mound,
18.vi.2000
,
S. A. Marshall
(
1 ♂
,
2 ♀
,
DEBU
)
.
Estrella valley
,
Pandora
,
20.ii.1984
,
carrion trap
,
H. Howden
(
2 ♂
,
DEBU
)
.
Guanacaste
.
Guanacaste
Cons. Area
,
Rincon de la Vieja
,
Las Pailas
,
1400m
,
Clusea
rosea
forest litter,
18.ii.1996
,
R. Anderson
(
1 ♀
,
DEBU
)
.
Heredia
,
La Selva
near
Puerto Viejo
, around dung ball rolled by
Canthon monillatus
,
2.ii.1990
,
N. Greig
(
1 ♂
,
DEBU
)
.
ECUA DOR: Pichincha.
Río Palenque Stn
,
25.ii.1979
, dung,
S.A. Marshall
(
1 ♂
,
DEBU
)
.
Esmeraldas.
11 km
SE
San Lorenzo
,
La Chiqita
,
5m
,
dung trap
,
10–11.vi.1975
(
3 ♀
,
DEBU
)
;
carrion,
9–10.vi.1975
(
1 ♀
,
DEBU
)
,
S.
Peck.
GUATEMALA
:
Peten
,
Tikal
,
dung trap
,
28– 30.vii.1978
,
Helava
&
Kukal
(
1 ♀
,
DEBU
)
.
GUYANA
:
MazaruniPotaro Dist.
,
Tukelt Falls
,
Potaro R.
300', primary rainforest,
human dung trap
,
27–29.ix.1990
,
B. Hubley
(
2 ♀
,
DEBU
)
.
MEXICO
:
Veracruz
,
8 mi
NNW Sontecomapan
, rainforest, human dung,
vii– viii.1971
,
A. Newton
(
3 ♂
,
2 ♀
,
DEBU
)
.
PANAMA
: BCI,
Barro Colorado
, excremento,
10.iii.1996
,
N. Eberhyid
(
3 ♂
,
3 ♀
,
DEBU
)
.
Canal Zone
,
Barro Colorado Island
,
malaise trap
,
vii.1967
,
W. W. Wirth
(
2 ♂
,
2 ♀
,
USNM
)
.
Canal Zone
,
Gamboa
,
Pipeline Rd.
,
vii.1967
,
malaise trap
,
W.W. Wirth
(
3 ♀
,
USNM
)
.
Canal Zone
,
Isla de Barro Colorado
, siguiendo una bola de excremento de
Canthon moniliatus
,
10.vi.1996
,
C. A. Medina
(
1 ♂
,
6 ♀
,
DEBU
)
.
PERU
:
Madre de Dios Prov.
,
Manu Natl. Pk
,
Cocha Cashu Biol. Sta.
,
380m
, mal. trap,
23–30.viii.1986
,
D.C. Darling
(
1 ♂
,
DEBU
)
.
VENEZUELA
:
Bolívar
,
10 km
S El. Dorado
,
200m
,
17.vii–7.viii.1986
,
B. Gill
(
57 ♂
,
54 ♀
,
DEBU
)
.
Bolívar
, km 40
Sta.
Elena
Icabaru Rd.
,
100m
,
4–6.viii.1986
,
B. Gill
(
2 ♂
,
DEBU
)
.
Bolívar
,
20 km
S El Dorado
,
220m
,
20–23.vii.1986
B.Gill
(
5 ♂
,
2 ♀
,
DEBU
)
.
Bolívar
,
33 km
S El Dorado
,
220m
,
2–7.viii.1986
,
B. Gill
(
22 ♂
,
14 ♀
,
DEBU
)
.
Bolívar
,
22 km
S El Dorado
, lowland rainforest, FIT,
25.vi–12.vii.1987
,
S.& J. Peck
(
63 ♂
,
37 ♀
,
DEBU
)
.
Aragua
,
Henri Pittier Natl. Pk.
,
Rancho Grande Biol. Stn.
,
v. 1998
,
Ashe
,
Brooks
&
Hanley
(
2 ♂
,
DEBU
)
.
Etymology: The specific epithet refers to the lack of shining patches on the male sternite 5.
Comments: The observation that this species sometimes follows dungrolling scarab beetles (see records by C.A. Medina above) suggests that it might be at least facultatively kleptoparasitic in the dung stores of scarabaeines. Obligate keptoparasitic sphaerocerids occur amongst southern Nearctic species in the genera
Ceroptera
and
Norbommia
, but kleptoparasitism has not yet been documented in neotropical sphaerocerids. Other
Robustagramma
species
(see notes under
R.
biangulatum
)
have been collected on dung being rolled by scarab beetles.