Geographic variation in U. S. populations of the tiger beetle Cicindela obsoleta Say (Coleoptera: Cicindelidae)
Author
Mawdsley, Jonathan R.
text
Insecta Mundi
2009
2009-09-25
2009
94
1
10
journal article
10.5281/zenodo.5167791
1942-1354
5167791
Cicindela obsoleta
Say
Cicindela obsoleta
Say (1823:143)
Type
destroyed, but identity well established.
Diagnosis
. A large to very large tiger beetle (length
13-20 mm
) associated with desert grasslands and woodlands in
Arizona
,
Colorado
,
Kansas
,
New Mexico
,
Oklahoma
, and
Texas
, with isolated populations in
Arkansas
and
Missouri
. Dorsal coloration may be matte black, brown, blue, olive-green, or bright green, but never strongly iridescent. Elytral markings variable, with yellow or white maculae and/or fasciae
Figure 1-9.
Adult habitus photographs of pinned specimens of
Cicindela obsoleta
in NMNH.
1)
Cicindela obsoleta obsoleta
Say
, male, Silver City, NM.
2)
Cicindela obsoleta obsoleta
, female, Carrizo Creek Picnic Area, Baca Co., CO.
3)
Cicindela obsoleta obsoleta
, male, Silver City, NM.
4)
Cicindela obsoleta obsoleta
X
Cicindela obsoleta santaclarae
, female, Silver City, NM.
5)
Cicindela obsoleta santaclarae
Bates
, syntype female, Santa Clara, Chihuahua, México.
6)
Cicindela obsoleta santaclarae
, male, Ft. Wingate, NM.
7)
Cicindela obsoleta santaclarae
, female, Ft. Wingate, NM.
8)
Cicindela obsoleta santaclarae
, female, Ft. Wingate, NM.
9)
Cicindela obsoleta santaclarae
, male, Ft. Wingate, NM.
often present. Pronotum subquadrate, with a thin band of reclinate setae along the lateral edges of the disc.
Subspecific taxonomy.
Four subspecies are recognized here, confirming the traditional taxonomic arrangement in
Cicindela obsoleta
(
Freitag 1999
;
Pearson et al. 2006
). Of the 1,424 specimens that I examined, 1,393 could be unequivocally assigned to a single subspecies on the basis of their elytral markings. The remaining
31 specimens
are more or less intermediate between the two forms that have been conventionally recognized as
C. o.
obsoleta
and
C. o. santaclarae
Bates. As discussed below, I interpret these forms as intergrades between these two subspecies.
Cazier (1954)
reviewed the Mexican subspecies of
C. obsoleta
and recognized two additional subspecific taxa,
C. o. latemaculata
Becker from
Durango
and
C. o. juvenilis
Horn from
Jalisco
,
Sinaloa
, and
Sonora
. However, Cazier’s treatment of
C. obsoleta
is limited, as it was based on material collected at just 11 localities in
México
(
Cazier 1954
). A more extensive study of the Mexican forms is needed;
Murray (1979)
reports the discovery of Mexican specimens which do not fit into any of the currently-recognized subspecific taxa. Even the status of the two subspecific taxa
C. o. latemaculata
and
C. o. juvenilis
can be questioned.
Cazier (1954)
relied on the presence of wide elytral markings to separate
C. o. latemaculata
from the other subspecies of
C. obsoleta
. However, similar markings are present in individuals from
U.S.
populations of
C. o. santaclarae
(e.g.
Figure 7, 9
). Thus,
C. o. latemaculata
may ultimately prove to be a synonym of
C. o. santaclarae
. Likewise,
C. o. juvenilis
differs from the other subspecies of
C. obsoleta
in lacking dense setae on the proepisterna and metepisterna (
Cazier 1954
), a significant morphological distinction which suggests that
C. o. juvenilis
may actually be a separate species. Additional material of these forms from additional collecting localities is needed in order to resolve these questions.
Figure 10-17.
Adult habitus photographs of pinned specimens of
Cicindela obsoleta
in NMNH.
10)
Cicindela obsoleta vulturina
LeConte
, female, Cisco, TX.
11)
Cicindela obsoleta vulturina
,
female, Henrietta, TX.
12)
Cicindela obsoleta vulturina
,
male, Forestburg, TX.
13)
Cicindela obsoleta vulturina
,
male College Station, TX.
14)
Cicindela obsoleta vulturina
,
male, 2.5 miles SW Calico Rock, AR.
15)
Cicindela obsoleta neojuvenilis
Vogt
, paratype male, S. W. Hidalgo Co., TX.
16)
Cicindela obsoleta neojuvenilis
, paratype female, S.W. Hidalgo Co., TX.
17)
Cicindela obsoleta neojuvenilis
, paratype female, S. W. Hidalgo Co., TX.
The following key is offered to assist in the separation of the
U.S.
subspecies of
C. obsoleta
Say. Users
should be aware that putative intergrades between
C. o.
obsoleta
and
C. o. santaclarae
have been collected in
New Mexico
and
Texas
and may also occur in
Arizona
(see further discussion in the section on intergrades below). These intergrades will run to
C. o. santaclarae
in this key.