A Review of Genus Cyclosomus Latreille (Coleoptera: Carabidae: Lebiinae: Cyclosomini) in Asia.
Author
Kavanaugh, David H.
Department of Entomology, California Academy of Sciences, 55 Music Concourse Drive, Golden Gate Park, San Francisco, CA 94118.
Author
Cueva-Dabkoski, Mollie
Student Science Fellow, California Academy of Sciences, San Francisco, and & 2355 Pearl Street, Santa Monica, CA 90405.
text
Proceedings of the California Academy of Sciences
2023
2023-02-15
67
21
493
537
journal article
299696
10.5281/zenodo.11512952
2b56e3b0-2274-4963-b243-9c991b07072c
0068-547X
11512952
Cyclosomus flexuosus
(Fabricius)
Figures 5
,
6
,
14B
,
15B
,
16B
,
17B
,
20
Carabus flexuosus
Fabricius, 1775:246
.
LECTOTYPE
, here designated, a male, deposited in
ZMUK
, labeled: “
Scolytus flexuosus
“ [handwritten]/ “
LECTOTYPE
Carabus flexuosus
Fabricius 1775
design. by D.H. Kavanaugh & M. Cueva-Dabkoski 2022” [red label].
Type
locality: eastern
India
.
Scolytus flexuosus
(Fabricius)
,
Fabricius (1790:221
;
1792:180
).
Cyclosomus flexuosus
(Fabricius)
,
Andrewes (1921:153
and 166, 1924a:464, 1927:105, 1930:365);
Heller
(1923:302);
Csiki (1932:1295)
;
Lorenz (2005:452)
;
Kavanaugh (2015)
.
Cyclosomus dytiscoides
Nietner, 1857:312
.
LECTOTYPE
, here designated, a female, deposited in
MFNB
, labeled: “
Ceylon
,
Nietner
” [handwritten]/ “
Type
” [red label]/ “
SYNTYPUS
Cyclosomus dytiscoides
Nietner 1857
” [red label]/ “
LECTOTYPE
Cyclosomus dytiscoides
Nietner 1857
design. by D.H. Kavanaugh & M. Cueva-Dabkoski 2023” [red label].
Paralectotypes
examined:
one female
, also in
MFNB
, labeled: “
Cyclosomus dytiscoides Nietner
” [handwritten]/ “Type” [red label]/ “
SYNTYPUS
Cyclosomus dytiscoides
Nietner 1857
labeled by MNHUB 2013” [red label]/ “
PARALECTOTYPE
Cyclosomus dytiscoides
Nietner 1857
design. by D.H. Kavanaugh & M. Cueva-Dabkoski 2023” [yellow label].
Type
locality:
Sri Lanka
,
Western Province
, Negombo.
Chaudoir (1876:31)
;
Bouchard
(1903:174);
Andrewes (1921:154
, 1927:105);
Csiki (1932:1295)
;
Kavanaugh (2015:281)
. Synonymy proposed by
Andrewes (1921:154)
Notes on types and nomenclature.
We follow
Andrewes (1921:31)
in recognizing the Fabrician specimen at
ZMUK
as the type of
C. flexuosus
and provide
lectotype
designations for both
C. flexuosus
and
C. dytiscoides
to promote nomenclatural stability.
Diagnosis.
Adults of
C. flexuosus
can be distinguished from those of other
Cyclosomus
species
in Asia by the following combination of character states: Body size larger for genus, BL males =
8.2 to 9.4 mm
, females =
8.3 to 9.8 mm
; body form (
Figs. 5A, 5C
,
6A, 6B
) slightly elongate ovoid; pronotum (
Fig. 14B
) relatively broader (ratio PWM/PL = 2.45 to 2.69), disc light reddish brown to rufopiceous, with lateral pale bands moderately broad but not sharply defined, anterior angles broad and broadly rounded apically, lateral margins smoothly arcuate, not sinuate near anterior angles; elytra with pattern of dark maculae more extensively developed than average in most specimens (
Figs. 5C
,
6A
) but highly varied and less than average (
Figs. 5A
,
6B
) in a few specimens, preapical dark spot present; elytral epipleuron with long setae over entire length (although many of these are broken off in many specimens); male median lobe with apical lamella slightly recurved dorsally in relation to ventral curvature of shaft in lateral aspect (
Fig. 16B
), apical lamella broadly triangular with a distinct, more narrowly-rounded projection apicomedially in dorsal aspect (
Fig. 17B
).
FIGURE
5.
Cyclosomus flexuosus
Fabricius. A.
Holotype male, dorsal habitus; B. Labels associated with
C. flexuosus
holotype; C.
Cyclosomus dytiscoides
Nietner
, lectotype female, dorsal habitus; D. Labels associated with
C. dytiscoides
lectotype. Scale lines = 1.0 mm.
FIGURE
6.
Cyclosomus flexuosus
Fabricius
, dorsal habitus. A. Dark male (Cinkona, Anaimalai Hills, Tamil Nadu, India); B. Pale female (Tiruchirappalli, Tamil Nadu, India). Scale lines = 1.0 mm.
In describing
C. flexuosus
,
Kavanaugh (2015)
incorrectly stated “Male with middle tarsomeres 1 to 3 not laterally expanded and without ventral pads of adhesive setae.” In fact,
C. flexuosus
males, like those of all the other
Cyclosomus
species
represented in Asia for which males are known, have middle tarsomeres 1 to 3 distinctly expanded in comparison with those in females and have two longitudinal rows of squamatous adhesive setae ventrally on tarsomeres 1 to 3. In contrast, most (four of six) species in the Afrotropical Region have the male middle tarsi similar to those of females in form (i.e., more slender) and in the absence of ventral adhesive setae.
This species demonstrates the greatest range of variation in elytral dark color pattern seen among all species in the Asian fauna. The extremes are represented in
Fig. 6
, with the most broadly developed dark pattern (
Fig. 6A
) covering more than 50% of the elytral surface, and the least developed pattern (
Fig. 6B
) restricted to the basal dark band, a typical longitudinal dark band, a relatively narrow middle dark band extended only to interval 4, and a small preapical spot. The patterns seen in the
type
specimens of
C. flexuosus
(
Fig. 5A
) and its junior synonym,
C. dytiscoides
(
Fig. 5B
), are close to the opposite extremes for the species, so it is certainly understandable that they would have been described as distinct species on the basis of different color patterns.
Members of this species share epipleura having relatively long setae throughout their length only with those of
C. philippinus
; but they differ from the latter in having a prepical pale spot present and pronota with the pale lateral bands less well-defined medially. Males of the two species differ markedly in the curvature of the male median lobe in lateral aspect (compare
Fig. 16B
with
Fig. 16E
) and shape of the apical lamella in dorsal aspect (compare
Fig. 17B
with
Fig. 17E
). The elytra color pattern of darker specimens of
C. flexuosus
is most similar to that seen in
C. sumatrensis
(
Fig. 11
) and some
C. suturalis
(
Fig. 12C
) specimens; but members of both of these species have long epipleural setae only on the humeral and subhumeral regions and progressively and distinctly shorter setae to toward the apex. Also, males of these species have the male median lobe less curved in lateral aspect (
Figs. 16F, G
) and the apical lamella of distinctly different shape (compare
Fig. 17B
with
Figs. 17F and 17G
).
Habitat distribution.
Not yet reported, but presumed to be restricted to sandy substrates in the vicinity of streams or other water bodies and any associated dune systems, and likely also to occur in such sandy areas along ocean shores. Several localities from coastal areas both on the Indian Subcontinent and in
Sri Lanka
likely represent occurrences in coastal sand beach or dune habitats. The apparent elevational range of this species extends from at or near sea level (
3 m
on Mannar Island,
Sri Lanka
) to at least
500 m
(near Kurseong in
West Bengal
, northern
India
).
Geographical distribution.
We have examined a total of
176 specimens
(
90 males
and
86 females
) from the following localities:
BANGLADESH
/
INDIA
: “Bengala” ([
one female
;
MFNB
]).
INDIA
([
two males
and
one female
;
IRSNB
]):
Arunachal Pradesh
:
Bhalukpong
(27.0333°/92.5833°,
150 m
,
26 May-3 June 2006
,
P. Pacholátko
collector [
two females
;
NHMUK
])
;
Gujarat
:
Kinara
([
one female
;
NHMUK
]);
Karnataka
:
Belagavi
([
one female
;
NHMUK
])
;
Shivamogga
([
one male
;
NHMUK
]);
Kerala
:
Malabar
([
16 males
and
17 females
;
IRSNB
], [
two females
;
NHMUK
])
;
Madhya Pradesh
:
Barwai
([
one males
and
three females
;
IRSNB
])
;
Odisha
:
Brahmapur
([
one female
;
NHMUK
])
;
Puducherry
:
Karaikal
(
Karaikal
,
July 1962
,
P.S. Nathan
collector [
eight male
and
four females
;
EMEC
],
August 1955
[
one male
;
NMNH
])
,
July 1956
[
16 males
and
seven females
;
CAS
]
,
[
one male
and
two females
;
MFNB
]), (
Nedungadu
,
June 1931
[
one female
;
NHMUK
],
10 May 1932
[
one male
and
one female
;
NHMUK
])
,
Mahé
(
Malabar Coast
,
July 1951
,
M. Maindron
collector [
12 males
and
three females
;
IRSNB
])
;
Tamil Nadu
:
Anaimalai Hills
(
Cinkona
,
1070 m
,
May 1966
,
P.S. Nathan
collector [
five males
and ten females;
MFNB
])
,
Chennai
([
one male
and
one female
;
NHMUK
])
,
Coimbatore
(
October 1958
[
three males
and
two females
];
NHMUK
])
,
Ramanathapuram
([
one male
;
IRSNB
])
,
Tiruchirappalli
(1905,
P. du Breuil
collector [
one male
and
four females
;
IRSNB
]
,
R.P. Castets
collector [
one male
and
two females
;
IRSNB
],([
two males
and
two females
;
IRSNB
], [
one female
;
MFNB
])
;
Uttarakhand
:
Kumaon Division
(
West Almora
,
November 1918
,
H.G. Champion
collector [
two females
;
NHMUK
])
;
West Bengal
:
Kurseong
(1904 [
three males
and
one female
;
IRSNB
])
;
“
Ind. Or.
” ([
one female
;
MFNB
])
;
“
Inde Meridionale
” ([
one female
;
IRSNB
])
;
“
South India
” ([
one female
;
NHMUK
])
.
NEPAL
([
one female
;
NHMUK
])
:
Bagmati Province
:
Chisapani Garhi District
(
Hetauda
,
540 m
,
26 September 1960
,
H. Brydon
collector [
one male
and
one female
;
CAS
])
;
Lumbini Province
:
Bardiya National Park
(
Babi River
,
200 m
,
28 June 2000
,
T.W. Harman
collector [
one female
;
NHMUK
])
.
SRI LANKA
([
one female
;
MFNB
]), ([
two males
and
one female
;
NHMUK
])
:
Sabaragamuva Province
:
Kitulgala
(
Kitulgala Rest House
,
150 m
,
24-26 October 1977
,
K.V. Krombein
,
T. Wijesinhe
,
M. Jayaweera
, and P.
A
.
Panawatta
collectors [
one male
;
NMNH
]),
Uggalkaltota
(
150 m
,
10-14 October 1970
,
O.S. Flint
,
Jr.
collector [
two males
;
NMNH
])
;
North Central Province
:
Polonnaruwa
(4
May
19080,
W.N. Mathis
,
T. Wijesinhe
, and
L. Jayawickrema
collectors [
one female
;
NMNH
])
;
Northern Province
:
Kondachchi
(
Ma Villu
,
11-12 April 1981
, K.V.
Krombein
, L.
Weeratunga
, and
P. Leanage
collectors [
one female
;
NMNH
]
,
Mannar Island
(
3.2 km
W of Pesalai
,
3 m
,
24 March 1970
,
Davis
and
Rowe
collectors [
six males
and
one female
;
NMNH
])
;
Western Province
:
Colombo
([
one female
;
NHMUK
])
,
Negombo
([
two females
;
MFNB
])
.
Specimens
without or with illegible locality data: (
5 July 1909
[
one male
;
NHMUK
])
([
one male
;
NHMUK
])
.
The known geographical range of
C. flexuosus
(
Fig. 20
) covers most of the Indian Subcontinent, from the southern base of the
Himalayan Mountains
in the north to
Sri Lanka
in the south. We have examined specimens from
Arunachal Pradesh, Gujarat, Karnataka, Kerala, Madhya Pradesh, Odisha
, Puducherry,
Tamil Nadu, Uttarakhand
, and
West Bengal
states in
India
, as well as
Nepal
, and
Sri Lanka
.
Kavanaugh (2015)
reported on a disjunct record of this species from “Nubia” (historical name for the area including southern
Egypt
and northern
Sudan
centered on the
Nile River valley
) and commented on that occurrence.
Geographical variation.
Although there is evident individual variation (
Figs. 5A, 5C
,
6
) in development of the dark color pattern of the elytra throughout the range of this species, we could not discern any particular geographic component to that variation.
Geographical relationships with other
Cyclosomus
species.
This species has been found synotopic only with
C. acutangulus
(in
Arunachal Pradesh
,
India
) at the northwesternmost known locality for the latter species. The range of
C. flexuosus
overlaps that of
C. vespertilio
sp. nov.
in northern
India
and
Nepal
, but these two species have not yet been found together. Known localities for
C. flexuosus
in northern West Bengal and
C. suturalis
in southernmost Sikkim are less than
30 km
apart, so at least some overlap in their ranges is likely. Because of uncertainty with respect to the respective geographical ranges of
C. inustis
,
C,
marginatus
, and
C. suturalis
(see discussions below), it is possible but not yet confirmed that one or more of these overlap with
C. flexuosus
at least in the eastern part of its range.