Taxonomic remarks, phylogeny and evolutionary notes on the leaf beetle species belonging to the Cryptocephalus sericeus complex (Coleoptera: Chrysomelidae: Cryptocephalinae)
Author
Sassi, Davide
text
Zootaxa
2014
3857
3
333
378
journal article
10.11646/zootaxa.3857.3.2
9682bd87-ff66-4cb6-b697-9a53822a5df0
1175-5326
231616
55FBFBCF-F9AF-4EAF-A74A-9A81E6A381B8
Cryptocephalus zambanellus
Marseul, 1875
Cryptocephalus zambanellus
Marseul, 1875
: 130
.
Type
locality: Monzambano,
Italy
.
Type
: not examined.
The taxonomy of
Cryptocephalus sericeus
seems rather confusing in determining the status of
Cryptocephalus zambanellus
Marseul. This
latter taxon has been considered by some authors as a subspecies of
C. sericeus
(
Warchalowski, 2003
,
Gómez-Zurita
et al.
, 2011
) and by others it was treated as a distinct species (
Lopatin
et al.
, 2010
;
Petitpierre, 2000
). It should also be noted that Burlini, who for decades represented the most authoritative entomologist in the study of European
Cryptocephalus
, had always considered
C. zambanellus
a subspecies of
C. sericeus
(
Burlini, 1956
)
. Because of these taxonomic uncertainties I re-examined this issue in detail. On the basis of specimens collected in
Italy
(Monzambano, near Mantua),
Cryptocephalus zambanellus
was described by
Marseul (1875)
as a species and not as a "variety", as erroneously reported by de
Monte (1948)
. Marseul separated it from
C. sericeus
because of the absence of the bituberculate small ridge on the anterior margin of the anal depression that characterizes male specimens of this taxon (fig. 10). Since then,
Weise (1881)
described and named specimens of
C. sericeus
collected near Trieste, in
Croatia
and Dalmatia as
C. sericeus
var.
intrusus
, distinguished from the nominal form on the basis of the same morphological characters, i. e. the lack of the bituberculate ridge. At that time the author did not know the taxon described by
Marseul (1875)
and later on he hastened to synonymize
intrusus
with
C. zambanellus
in "additions and corrections" in a footnote of his following work (
Weise, 1893
). In the following years
C. zambanellus
was deemed alternately as a distinct species (
Breit, 1918
;
Winkler, 1930
;
Porta, 1934
;
Zangheri, 1969
) or as a "variety" or subspecies of
C. sericeus
(
Weise, 1906
;
Clavareau, 1913
;
Ulrich, 1923
; de
Monte, 1948
;
Müller, 1952
;
Burlini, 1956
).
Besides, de
Monte (1948)
resurrected the name
intrusus
from synonymy with subsp.
zambanellus
, proposing it as a distinct subspecies of
C. sericeus
for specimens collected from Venezia Giulia only, highlighting peculiarities in the structure of the first sclerite of endophallus and in the shape of the male anal pit. He acknowledged, however, that from some localities (Tolmin, Postojna) there were specimens with ambiguous features. Besides, de Monte reported a rather strong variability in specimens from the Dalmatian coast and from the Velebit. However, he still assigned these latter populations, with some doubt, to
C. sericeus
ssp.
zambanellus
.
In more recent times
Rozner & Rozner (2008)
awarded a specimen collected in the
Republic of Macedonia
(Kratovo, Zguri-pass,) to the taxon
C. zambanellus
.
After the analysis of several tens of specimens from Venezia Giulia,
Slovenia
,
Croatia
and Dalmatian Islands, I feel the situation can be evaluated as follows. I confirm the existence of intermediate specimens, i.e. “
intrusus
” sensu de
Monte (1948)
, between
C. zambanellus
and
C. sericeus
in populations spread in Italian territories between the valley of Tagliamento river and the state border, on the whole Istrian peninsula up to Rijeka, and on Slovenian territories up to the vicinity of Postojna. It must therefore be noted that the area covered by these intermediate populations joins to the north and east with that of
C. sericeus
, and abruptly bisects to the west the range of
C. zambanellus
, as the populations of the Dalmatian coast south of Istria should be attributed to the latter taxon (pers. obs., but see also de
Monte, 1948
; Müller, 1953). On the other hand it is remarkable that
C. zambanellus
and
C.
s
ericeus
never show transitional forms along the northern and western border area. In
Italy
,
C. sericeus
is reported only from a single locality (Tarvisio) very close to the Austrian border (
Burlini, 1956
). In
France
,
C. sericeus
can be found at a short distance from the Italian border, being present in the Queyras and Savoye (Lanslevillard) while maintaining the typical habitus. All the Italian specimens I examined, even if collected very close to the French border (i.e. Vinadio, Limonetta, Sampeyre) belong with no doubts to
C. zambanellus
. Conversely, transalpine and Central European specimens never reveal morphological characters that match the pattern of the latter form. Considering the broad extent of
C. sericeus
’ range, ambiguous morphological intermediates (“
intrusus
”) occurring in the northeastern part of
zambanellus
' range may be explained with the existence of a moderate area of introgression between two otherwise distinct species that reveal a global well-established genetic isolation. For this reason, I reiterate the opportunity to compose this taxonomic framework:
Cryptocephalus zambanellus
Marseul, 1875
: 130
stat. nov.
Cryptocephalus intrusus
Weise, 1881
:
183
n. syn.
Cryptocephalus sericeus intrusus
Weise (
De Monte, 1948
: 471
)
.