A key to American genus Merobruchus Bridwell (Coleoptera: Chrysomelidae: Bruchinae) with descriptions of species and two new host plant records for the subfamily
Author
Manfio, Daiara
Author
Ribeiro-Costa, Cibele Stramare
text
Zootaxa
2016
4078
1
284
319
journal article
46790
10.11646/zootaxa.4078.1.25
e94a2297-93a5-4d20-b957-670b655f214e
1175-5326
263743
78037DEE-A4F0-4E28-8135-EFD57552C3D0
Merobruchus pIckelI
(
Pic, 1927
)
(
Figures 22
,
40
,
45–46
,
69
,
93
,
119
,
143
)
Pseudopachymerus pickeli
Pic, 1927
: 32
(original description,
type
locality: "
Brazil
",
type
depository: MNHN),
Bondar, 1936
: 26
(distribution),
Kingsolver & Silva, 1991
: 414
(citation).
Caryedes pickeli
:
Blackwelder, 1946
: 758
(distribution),
Udayagiri & Wadhi, 1989
: 76
(catalogue).
Gibbobruchus pickeli
: Zacher, 1952: 467
(host plant; questionable if related to
P. pickeli
Pic, 1927
).
Merobruchus pickeli
:
Kingsolver, 1988
: 2
, 4, 63 (new combination, distribution, taxonomy),
Kingsolver & Silva, 1991
: 414
(citation), Romero-Nápoles & Johnson, 2004: 386 (distribution questionable).
Pseudopachymerus pickeli subnotatus
Pic, 1927
: 32
(original description,
type
locality: "
Brazil
").
New synonym.
Caryedes pickeli
var.
subnotata
Blackwelder, 1946
: 758
(distribution).
Pseudopachymerus steinbachi
Pic, 1934a
: 116
(synonymized by
Kingsolver, 1988
: 2
).
Caryedes steinbachi
:
Blackwelder, 1946
: 758
(distribution),
Udayagiri & Wadhi, 1989
: 77
(distribution).
Material examined.
Type
material.
Pseudopachymerus pickeli
Pic, 1927
and
Pseudopachymerus pickeli
var.
subnotatus
Pic, 1927
.
Holotypes
deposited in
MNHN
, females (
Fig. 156
): Labels: (1) “360” (2) “
Brésil
/São Bento/ (Dª B. Pickel)” [Handwritten] (3) “sementes de/Pithecolobium/
saman Benth
/
v.aculifolia
” [Handwritten] (4) “
Pseudopachymerus
/prob stenocephalus” [Handwritten] (5) “
Pickeli
n sp/et v. subnotatus/mihi” [Handwritten] (6) “
HOLOTYPE
” [Red label printed in black] (7) “
Pseudopachymerus
/
pickeli Pic
Type
/Marked +/
P. pickeli v. subnotatus
/Pic/unmarked/specimen
Type
/J. M. Kingsolver´72” [Handwritten] (8) “
Merobruchus
/
pickeli
(
Pic, 1927
)
/ Ribeiro-Costa, C.S. det. 2007”.
Additional material.
BRAZIL
.
1, Chapada, Chapada Forest, May, Acc.No.2966, homotype label (
USNM
).
Mato Grosso:
7, Cuiabá, 1987, Nonato P. & Dorval A. col., semente de sete-casca (popular name of
Samanea tubulosa
) (
DZUP
); 3, Cuiabá, 987, Nonato P. & Dorval A. col., semente de chico-magro (
DZUP
).
Redescription,
holotype
.
Body length: 3.88 mm; width: 2.53 mm.
Integument.
Dorsum
(
Fig. 22
): pronotum reddish brown and dark brown; elytron bicoloured, anterior half brown and posterior half dark brown.
Antenna
: pale brown (
Fig. 36
).
Ventral region
: reddish brown and dark brown except anterior and middle legs pale brown (
Fig. 36
).
Pygidium
(
Fig. 69
): reddish brown and dark brown.
Pubescence.
Dorsum
(
Fig. 22
): pronotum pale brown and yellowish gray, pubescence denser at lateral; scutellum white; elytron variegated, pale brown, white and coppery.
Ventral region
: mostly white; abdominal ventrites uniformly pubescent (
Fig. 36
).
Pygidium
(
Fig. 69
): white and yellowish gray, homogeneous and dense, except spots with slightly sparse pubescence.
Body.
Subquadrate body.
Head
: with occipital sulcus (
Figs 2
,
40
); ocular index 3.06; ocular sinus 0.18 mm (
Fig. 2
); postocular lobe moderate (
Fig. 36
); frons slightly elevated, with conspicuous frontal carina, microsculptate, with regular borders, not enlarged at base (
Figs 2
,
40
); frontoclypeal carina distinct.
Antenna
: serrate, antennomeres 4–10 with the same width (
Fig. 36
); antennomere 11 longer than wide.
Pronotum
: lateral margins straight in dorsal view (
Fig. 22
); basal lobe with straight margin; median gibbosity slightly elevated, anterior region divided by shallow longitudinal sulcus (
Fig. 22
); lateral gibbosities slightly elevated (
Fig. 22
); coarse punctation dense at disc, intermixed with fine punctation all over pronotum (
Fig. 22
); lateral carina absent.
Scutellum
: wider than long (
Fig. 22
), bidentate.
Elytron
: humeral gibbosity conspicuous (
Figs 4
,
22
); basal gibbosity absent (
Figs 45–46
); striae regular in course, free apically and visibly impressed, except 4–6 formed only by isolate punctation (
Fig. 45
); striae 3–5 with basal denticle (
Fig. 46
).
Mesoventrite
: mesoventral process rounded apically; postmesocoxal sulcus rounded, following the curvature of the coxa (
Fig. 47–48
).
Metaventrite
: not protuberant in lateral view (
Fig. 36
); metanepisternum with sparse, coarse punctation; dorsal carina incomplete, not limiting posterior corner and margin.
Hind
leg
: femur in lateral view projects beyond
pygidium
(
Fig. 4
); pecten with 4 teeth; internal margin without denticles at anterior region before pecten. Tibia, external face smooth, not microserrate; lateroventral carina complete; mucro longer than width of tibia apically; coronal tooth absent; curvature of tibia at external margin reaching half-length of tibia.
Abdomen
: last ventrite, median apical border with arcuate emargination, with short lateral projections (
Fig. 55
).
Pygidium
: entirely convex; median lateral tubercles slightly elevated; apical margin truncate.
Male genitalia.
Median lobe
(
Fig. 119
): length about
4 x
maximum width of base of ventral valve. Ventral valve arcuate, wider than long and narrower than median lobe apically. Apical region with dense spines, short plates bi- or tridentate, sparse denticles. Median region with sparse denticles; Y-shaped sclerite with upper stem straight and lateral stems curved; four dentate sclerites with large base, two with about
2 x
the size of the other. Basal region with spicules. Basal hood bilobate, wider than largest width at base of ventral valve.
Tegmen
(
Fig. 143
): lateral lobes moderately emarginate, emargination reaching slightly over half of its length; external margin straight and internal margin concave; apex truncate, oblique, convergent; with projections turned toward the ring.
Variability.
Body length (n = 10): 3.37–4.15 mm; width: 2.3–2.72 mm.
Integument.
Pygidium
: reddish brown.
Pubescence.
Dorsum
: pronotum with sparse white pubescence; elytron sometimes with sparse yellowish gray pubescence.
Pygidium
: white.
Body.
Head
: ocular index 3.65–3.46; ocular sinus 0.11–0.16 mm.
Hind
leg
: femur, pecten with 5 teeth.
Female.
Abdomen
: last ventrite, median apical border with arcuate emargination, with long lateral projections forming digitate process (
Fig. 52
).
Pygidium
: almost straight in female (
Fig. 93
).
Diagnosis.
Merobruchus pickeli
differs from
M. bicoloripes
by the antennae entirely pale brown (
Fig. 36
), pronotum with slightly elevated median gibbosity and with straight lateral margins (
Fig. 22
), elytron with a denticle at the base of the striae 3–5 (
Fig. 46
), the lateral lobes of the tegmen of male genitalia (
Fig. 143
) with an oblique and convergent apex and with projections toward the ring.
Distribution.
Brazil
(Mato Grosso).
Host plant.
Fabaceae
,
Mimosoideae
,
Ingeae
:
Samanea tubulosa
(Benth.) Barneby & J.W.Grimes
(=
Pithecellobium saman
var.
acutifolium
Benth
)
Remarks
. We requested the
type
material of
Pseudopachymerus pickeli
from the MNHN and received two specimens glued on the same paper rectangle. In the original description of
Pseudopachymerus pickeli
, Pic
also described
Pseudopachymerus pickeli
var.
subnotatus
. Next to one exemplar there is a marking red cross. This mark is also present in the upper half of a handwritten label by Kingsolver (“
Pseudopachymerus
/
pickeli
Pic
Type
/ marked +”;
Fig. 156
) showing that this is the exemplar named
P. pickeli
. The other exemplar, unmarked, is associated with the information in the lower half of the same label (“
P. pickeli v. subnotatus
/ Pic
Type
unmarked specimen/ J. Kingsolver 72”;
Fig. 156
). Both specimens differ slightly only by the pubescence colour, so the taxa are here synonymized. Romero-Nápoles & Johnson (2004) included
Nicaragua
as a distribution record for
M. pickeli
and cited
Kingsolver (1988)
. However,
Kingsolver (1988)
did not deal about geographical distribution of
M. pickeli
, only mentioned that this species is South American. So,
Nicaragua
is a questionable record.