Palms and pollen beetles: two new anthophilous beetle species of Meligethinus from Mozambique (Coleoptera: Nitidulidae: Meligethinae)
Author
Sabatelli, Simone
Author
Liu, Meike
College of Agriculture, Yangtze University, Jingzhou, China
Author
Cline, Andrew Richard
Plant Pest Diagnostics Center, California Department of Food & Agriculture, Sacramento, CA, USA
Author
Lasoń, Andrzej
ul. Wiejska 4 B / 85, 15 - 352 Białystok, Poland
Author
Macuvele, Suzana
Museu de História Natural, Universidade Eduardo Mondlane, Travessia do Zambeze 104, Maputo 1100, Mozambique Corresponding author. liumk 2009 @ 126. com
Author
Muambalo, Kisimenda
Museu de História Natural, Universidade Eduardo Mondlane, Travessia do Zambeze 104, Maputo 1100, Mozambique Corresponding author. liumk 2009 @ 126. com
Author
Chuquela, Lucilia
Museu de História Natural, Universidade Eduardo Mondlane, Travessia do Zambeze 104, Maputo 1100, Mozambique Corresponding author. liumk 2009 @ 126. com
Author
Audisio, Paolo
text
Zootaxa
2020
2020-11-22
4802
1
journal volume
10.11646/zootaxa.4802.1.2
1175-5326
DF345B6E-DF9A-448E-B0DE-A45ED0309AA0
Meligethinus hamerlae
sp. nov.
(
Figs 1
e–f, i, p)
Diagnosis.
Narrowly elongate, moderately transversely convex, uniformly testaceous-orange. Similar in external shape and color to
M. mondlanei
sp. nov.
described above and similar to the sympatric
M. suffusus
, but easily differentiated from the former by the markedly distinct shape of metatibiae in males, and the different shape of male and female genitalia, as well as the presence of a small dorsal, medial, pre-distal projection on the female pygidium. The new species is easily differentiated from the latter by the presence of the medial projection on the female pygidium, by the markedly distinct shape of male genitalia, and the usually paler body color. This new species is likely closely related to the central African
M. muehlei
Jelínek, 1992
, which is on average larger and darker, characterized by completely different male metatibiae, a markedly larger and longer pygidial female projection, and distinctively shaped male and female genitalia.
Description.
(male
holotype
).
Size
: body length
2.4 mm
, width
1.10 mm
. Body narrowly elongate, scarcely transversely convex, uniformly testaceous-orange. Dorsal surface rather densely, finely and shallowly punctate (spaces between pronotal and elytral punctures ~1.5–2× diameter), with dull and shagreened interspaces; elytra without traces of transverse strigose sculpturing. Pronotum trapezoidal in shape, with widely arcuate lateral sides, maximum width near posterior five sixths. Pubescence on pronotum and elytra sparse, golden-whitish, moderately long and distinct, each seta markedly shorter than antennomere 6, slightly longer along posterior base. Body uniformly orange-yellowish, without pale areas, including peripheral margins (pronotal carina) of pronotum; legs and antennae uniformly yellowish-orange, testaceous, with antennal club distinctly darker, pale brown. Antennal club elongate, symmetrical, without differences between sexes. Proximal base of pygidium with normal, “V” shaped medial impression, directed posteriad. Prosternal process broadly rounded distad, maximum width near distal 2/5. Metaventrite almost flat, only slightly depressed in posterior half, with a scarcely distinct longitudinal impression. Last abdominal ventrite bearing two rather small proximal semicircular impressions, diameter nearly 1.2× the diameter of an eye.
Legs
: protibia (
Fig. 1k
) wide, triangular, as in
M. suffusus
Kirejtshuk, 1980
, protarsus nearly as wide as length of antennomere 3 (ratio WFTA/LFTA ≈ 0.25). Mesotibia wide, trapezoid shaped. Metatibia (
Fig.
1m
) scarcely wide, along inner side almost simple and regular in posterior half, not denticulate, almost identical to that of
M. suffusus
Kirejtshuk, 1980
, exhibiting no marked sexual dimorphism.
Male genitalia
: distinctively shaped, with elongate and subparallel-sided tegmen (
Fig. 1e
), aedeagal median lobe rather small, maximum width at proximal fifth, ratio LEAE/WIAE = 2.15–2.20 (
Fig. 1f
); aedeagal apex narrowly truncate with a distinct and narrowly chisel-shaped distal apex, ~1/5 as wide (0.20×) as maximum basal aedeagal width (
Fig. 2f
). Ratio DTIN/LETE ≈ 0.44–0.48, median excision of tegmen narrow along first four-fifths of its length; ratio LETE/WITE = 1.40–1.42.
Female
: Protibia rather wide, triangular, slightly narrower than males, protarsus slightly narrower than males (ratio WFTA/LFTA ≈ 0.22). Mesotibia wide, trapezoid as in males. Metatibia simple and uniformly slightly nar- rower than males, along inner side almost rectilinear and not denticulate. Pygidium with a small but distinct median obliquely positioned conical protuberance directed posteriad, similar to females of
Meligethinus muehlei
from
Rwanda
(
Jelínek 1992
;
Fig. 1n
), but smaller (
Fig. 1p
). Ovipositor rather small and moderately sclerotized, not darkened toward the moderately blunt distal apex, exhibiting short styli, similar to that exhibited by
M. suffusus
(
Kirejtshuk 1980
;
Fig. 1h
), although exhibiting a slightly narrower distal gonocoxal apex (
Fig. 1i
). Ratio STLE/DSIA ≈ 0.40; ratio STLE/CGOW ≈ 0.17; ratio GONL/CGOW ≈ 3. Ratio OVPL/GONL ≈ 2.15.
Variation
: Overall body sizes range from
1.9–2.6 mm
(length) and
0.90–1.20 mm
(width).
Examined material.
Holotype
, male:
Mozambique
:
Maputo Province
, Inhaca Island, Farol,
10–15 m
a.s.l.,
25°58’22”S
,
32°59’08”E
,
21.ix.2018
, P. Audisio & S. Sabatelli lgt, sparsely forested and bushy area, beating male inflorescences of
Phoenix reclinata
Jacq. (Arecaceae)
(MHNMM).
Paratypes
:
10 males
,
13 females
; same data as
holotype
,
2 males
,
2 females
(MHNMM, CAR-MZUR); same locality,
27.ix.2019
, S. Sabatelli lgt, open and sparsely bushy area, beating male inflorescences of
Phoenix reclinata
Jacq. (Arecaceae)
,
6 males
,
8 females
(MHNMM, CAR-MZUR, CAS, CLA, ACC, NMPC); same locality, road between Farol and the Marine Biological Station,
10–15 m
a.s.l.,
26°00ʹ26ʹʹS
,
32°56ʹ37ʹʹE
,
27.ix.2019
, S. Sabatelli lgt, open and sparsely bushy area, beating male inflorescences of
Phoenix reclinata
Jacq. (Arecaceae)
,
2 males
,
3 females
(NMMU, CAR-MZUR).
Distribution.
This species is known from Inhaca Island in southern
Mozambique
(
Fig. 3
). The host-plant
Phoenix reclinata
is widespread in Eastern Africa (see above information on
M. mondlanei
sp. nov.
;
Coates Palgrave 2002
; see also pza.sanbi.org/phoenix-reclinata). The geographic range could be wider, potentially including at least part of these areas. However, several attempts (
2018–2019
) aimed to collect
M. hamerlae
sp. nov.
in nearby localities of continental southeastern
Mozambique
near
Maputo
failed in producing any additional specimens. The apparently exclusive presence of this new species at Inhaca is odd, considering this small island is separated from coastal areas of southeastern
Mozambique
by a shallow sea that did not create a barrier with the mainland during the most recent Würm Glaciation.
Host-plants.
This species appears to be strictly associated with male inflorescences of
Phoenix reclinata
Jacq. (Arecaceae)
. All specimens of the
type
series were collected by sweeping flowering males in conjunction with the more abundant
Meligethinus dolosus
,
M. peringueyi
, and
M. suffusus
, as well as a few specimens of the locally less abundant
M. mondlanei
sp. nov.
, and
M. humeralis
.
Habitat.
Locality data indicate this species prefers edges of sparsely forested and bushy areas, in sandy habitats close to the sea at very low altitudes.
Phenology.
The few available specimens were collected in middle and late September, which likely indicates adult activity from late August to early October.
FIGURE 1.
Male genitalia (tegmen and median lobe of the aedeagus) of
Meligethinus
spp.:
a–b
,
Meligethinus mondlanei
sp. nov.
, male paratype from Inhaca Island, Mozambique;
c–d
,
Meligethinus suffusus
, male from Inhaca Island, Mozambique;
e–f
,
Meligethinus hamerlae
sp. nov.
, male paratype from Inhaca Island, Mozambique; ovipositor (ventral view) of
Meligethinus
spp. (
i
: distal apex only):
g
,
Meligethinus mondlanei
sp. nov.
, female paratype from Inhaca Island, Mozambique;
h
,
Meligethinus suffusus
Kirejtshuk, 1980
, female from Inhaca Island, Mozambique;
i
,
Meligethinus hamerlae
sp. nov.
, female paratype from Inhaca Island, Mozambique; front tibiae of
Meligethinus
spp.:
j
,
Meligethinus mondlanei
sp. nov.
, male paratype from Inhaca Island, Mozambique;
k
,
Meligethinus suffusus
, male from Inhaca Island, Mozambique; hind tibiae of
Meligethinus
spp.:
l
,
Meligethinus mondlanei
sp. nov.
, male paratype from Inhaca Island, Mozambique;
m
,
Meligethinus suffusus
, male from Inhaca Island, Mozambique; dorso-lateral view of the elytral apices and of female pygidium of
Meligethinus
spp.:
n
,
Meligethinus muehlei
from Kibuye, Rwanda;
o
,
Meligethinus suffusus
from Inhaca Island, Mozambique;
p
,
Meligethinus hamerlae
sp. nov.
, female paratype from Inhaca Island, Mozambique. Scale bar: 0.2 mm (Figs a–m); 0.5 mm (Figs n–p).
FIGURE 2.
Habitus of
Meligethinus mondlanei
sp. nov.
, male paratype from Inhaca Island, Mozambique. Scale bar: 1 mm. Photo by Gareth Powell and Seth Bybee, Provo, USA.
Etymology.
The specific epithet honors Maria Grazia Hamerl, mother of the senior author S. Sabatelli.
Taxonomic remarks.
As reported above, this new species is similar in external shape to the sympatric
M. mondlanei
sp. nov.
and especially to the sister species
M. suffusus
(see below), being otherwise unmistakable due to the peculiar shape of the female pygidium (
Fig. 1p
), and the distinctly different shape of the male genitalia (
Figs 1
e–f), in particular the distinctly more narrowly chisel-shaped distal apex of the aedeagus (distinctly wider in
M. suffusus
:
Figs 1
c–d). The shared presence of a pre-distal conical protuberance on the female pygidium also suggests a close taxonomic relationship of the new species to the larger
Meligethinus muehlei
from
Rwanda
(
Jelínek 1992
), which is easily differentiated from the new species by the different male and female genitalia, a much larger size of the pygidial conical protuberance in females (
Fig. 1n
), darker body color with large, dark brown elytral spots, and longer golden hairs on legs in males (
Jelínek 1992
). Preliminary molecular analyses of the genus
Meligethinus
(Sabatelli
et al.
, unpublished data) demonstrates that the sympatric and syntopic
M. hamerlae
sp. nov.
and
M. suffusus
are sister species, amply separated by an average genetic
p
-distance (COI gene) of ≈ 0.6, indicating a well-estab- lished specific differentiation, combined with a clear common origin from a shared most recent ancestor.