Bruchinae (Coleoptera: Chrysomelidae) from Socotra Island
Author
Delobel, Alex
text
Acta Entomologica Musei Nationalis Pragae
2012
2012-12-17
52
373
380
journal article
10.5281/zenodo.5339503
0374-1036
5339503
Callosobruchus rhodesianus
Pic, 1902
Material examined
(
5 spec.
).
YEMEN
:
SOCOTRA ISLAND
:
Wadi Ayhaft
,
12°36′38″N
53°58′49″E
,
190 m
,
24.– 26.xi.2003
,
1 spec.
,
D. Král
leg. (
CBAD
)
;
Sirhin area
,
Dixam Plateau
,
12°31′08″N
53°59′09″E
,
812 m
,
1.–2.xii.2003
,
1 spec.
,
P. Kabátek
leg. (
NMPC
)
;
Firmihin
,
12°28′27″N
54°0′54″E
,
400–500 m
, at light,
6.–7.ii.2010
,
1 spec.
,
L. Purchart
&
J. Vybíral
leg.(
NMPC
)
;
Aloove area
,
Hasan
vill. env.,
12°31.2′N
54°07.4′E
,
221 m
,
9.–10.xi.2010
,
1 spec.
,
J. Hájek
leg. (
NMPC
)
;
Dixam
plateau,
Firmihin
(
Dracaena
forest),
12°28.6′N
54°01.1′E
,
490 m
,
15.–16.xi.2010
,
1 spec.
,
J. Hájek
leg. (
NMPC
)
.
Distribution.
Angola, Benin, Ivory Coast, Kenya, Senegal, Togo, Yemen, Zimbabwe.
First record from
Socotra Island
.
Comments.
Socotran specimens differ markedly from those from mainland Africa: prescutellar lobes are much less markedly convex, are covered with dense pale yellowish (instead of pure white) setation, and elytral vestiture is much less contrasted (almost uniformly pale fulvous in some specimens). Such differences in external morphology would possibly justify a separation at species level. Examination of male genitalia however shows that the aedeagus of Socotran specimens is perfectly identical with that of specimens from East Africa. The median pair of dented sclerites in the internal sac is clearly different in specimens from West Africa, so that populations from
Socotra
appear more closely related with Kenyan than with West African populations.
Callosobruchus rhodesianus
is a well-known pest of cowpeas,
Vigna unguiculata
(L.) Walp. (
Fabaceae
:
Phaseoleae
:
Phaseolinae
), both in the field and in stores. According to
TUDA et al. (2006)
, its wild populations favour dry areas with a long dry season, which explains the ability of this species to use dry and hard beans as a food source. It is also recorded from another
Phaseolinae
,
Nesphostylis holosericea
(Welw. ex Baker) Verdc. (
GILLON et al. 1992
)
, but its larvae can also attack members of the subtribe
Cajaninae
such as
Cajanus cajan
(L.) Millsp.
AMEVOIN et al. (2005)
showed that
C. rhodesianus
populations are outcompeted by
Callosobruchus maculatus
when both species coexist in the same stored seeds.