New species of the Scarabaeus subgenus Scarabaeolus Balthasar, with a review of the subgenus (Scarabaeidae: Scarabaeinae: Scarabaeini)
Author
Zidek, Jiri
Author
Pokorný, Svatopluk
text
Insecta Mundi
2018
2018-03-30
611
1
35
journal article
10.5281/zenodo.3726987
80783542-5446-42b3-a9bd-177b0e4ec73a
1942-1354
3726987
CF6C1B9C-2EC0-4220-BED7-6402A6C9D175
Scarabaeus
(
Scarabaeolus
)
lizleri
Zidek and Pokorný
,
sp. n.
Fig. 9–12
Type
locality.
RSA
,
Northern Cape Province
,
30 km
SE of Alexander Bay.
Type
material.
HTm from
type
locality, leg.
R
.
Lízler
9.X.2000
.
PT (179): 172 from
type
locality, leg.
R
.
Lízler
9.X.2000
;
\\
2 from
RSA
,
Richtersveld
,
Port Nolloth
,
leg.
Endrödi-Younga
4.X.1976
;
\\
1 from
Richtersveld
,
Manganese
mine, leg.
Endrödi-Younga
10.X.1976
; \\
2 from S.W. Afr. [
Namibia
],
Namib
,
Obib
dunes, leg.
Endrödi-Younga
20.IX.1973
; \\
2 from S.W. Afr. [
Namibia
],
S. Namib
,
Oranjemund
, leg.
Endrödi-Younga
28.VII.1981
.
HT+10 PT at
TMSA
, 10 PT at
BMNH
, 10 PT at
OXUM
, 10 PT at
MNHB
, 8 PT at
NMPC
, 131 PT at
GWPC
.
Etymology.
Named for Robert Lízler of
Hradec Králové
,
Czech Republic
, who collected nearly the entire
type
series.
Description of
holotype
.
Length
15 mm
. Black with reddish-orange elytra, glossy.
Head.
Clypeus without ventral keel, teeth weekly upturned, spaces between them U-shaped, space between medial teeth wider than that between medial and lateral teeth; anterior part with sparse asperate and setose punctures that posteriorly change to setose granules. Genae separated from clypeus by narrow excisions, their sculpture somewhat finer than that of clypeus, front end of each gena sharply pointed. Clypeus/frons boundary with an inconspicuous broad and smooth tubercle. Smooth sagittal line present throughout length, narrow on clypeus, widest on frons and narrowing toward vertex. Pubescence rusty brown, antennal club brownish yellow.
Pronotum.
Bordered all around, with a distinct smooth sagittal line, disc with sparse deep, setose punctures that become smaller and more closely spaced anteriorly and laterally. Lateral margins evenly rounded, coarsely serrate, with long hairs. Front angles obtuse, pointing outward, hind corners evenly rounded. Basal margin lined by a shallow groove with irregularly spaced setose punctures; medial part of base weakly lobate.
Scutellum
.
Exposed, small, triangular.
Elytra.
With humeri well developed, indistinctly striate, striae micropunctate. Intervals smooth and glossy, first interval flat on disc, convex and sparsely punctate posterolaterally. Second through fifth intervals nearly impunctate; sixth and seventh intervals weakly arched; suture and first interval black.
Pygidium
.
Obliquely triangular, bordered all around, smooth on disc and punctate near margins.
Venter.
Metasternum with posterior longitudinal furrow and keeled anterior process. Ventral pubescence dark brown.
Legs.
Protibia curved inward at level of second tooth, lateral margin densely serrate, medial margin densely granulose. Profemoral anteroventral carina without proximal tooth. Mesotibia with two spurs. Lateral margin of metatibia without transverse carinae. Pubescence dark brown.
Aedeagus.
Parameres shorter than phallobase, in lateral view dorso-ventrally parallel- sided, without ventral tooth and with truncated tips.
Variability.
Length
10–15 mm
, elytra prevalently bright to dark reddish orange, frequently with scattered small blackish spots, but in some specimens entirely dark brown with reddish hue.
Comparison.
The dorsal habitus of the new species is indistinguishable from
S. rubripennis
(Boheman)
(
Fig. 13–16
). In ventral view
S. lizleri
sp. n.
has a larger and more keeled metasternal process, but this cannot serve as a reliable diagnostic character. However, the two species can be readily separated on the presence of a large, sharp anteroventral tooth at the proximal end of the profemur in
S
.
rubripennis
, which is absent in the new species. The aedeagi of both species do not have a ventral tooth (merely a minute, barely noticeable tubercle) and differ only in proportions, with the phallobase longer than the parameres in
S
.
lizleri
and vice versa in
S
.
rubripennis
. Another species with reddish-brown but much darker elytra is
S
.
knobeli
Ferreira
from southern
Angola
(HT) and northwestern
Namibia
(
Fig. 21–24
), which can be separated from the other two species on having sparsely and shallowly punctate elytral intervals, only one mesotibial spur, and
pygidium
terminating in a short, outward curved spine.
Biology.
According to R. Lízler (in litt.) the
type
locality is about
10 km
from the shore, only
10–20 m
above the sea level, and has the character of a semidesert with small dunes and interspersed rocky outcrops. Vegetation consists of sparse “tamarysk” brush and succulents, and herbivorous mammals include lagomorphs, small antelope, goat and sheep; large ruminants are absent. At the time of capture of
S. lizleri
the temperature fluctuated between close to freezing at night and 30–35° C at mid-day, and the area experienced strong winds. The beetles were taken at human dung between 8 and 11 a.m. and again in the late afternoon and at dusk. It thus is a diurnal–crepuscular species that avoids daily thermal maxima more than minima, because in the early morning beetles were observed flying although the temperature was still only about 5° C.
The localities of the
type
series are in
Northern Cape Province
close to the southwestern
RSA
/
Namibia
border and just across the mouth of the Orange River in southernmost
Namibia
(Oranjemund, TMSA specimens), whereas localities of
S
.
rubripennis
are more to the north in the Namib desert—Kuisip (HTm), Namtib dunes (TMSA specimens) and Sessriem (BMNH and OXUM specimens). The two species thus are close neighbors and the question arises whether north of the Orange River they could not be sympatric, separated by diel activity or chemical stimuli. We have found no evidence of hybridization in the morphology of about
200 specimens
examined.