Two Eocene species of Culiseta (Diptera: Culicidae) from the Kishenehn Formation in Montana
Author
Harbach, Ralph E.
Author
Greenwalt, Dale
text
Zootaxa
2012
3530
25
34
journal article
10.5281/zenodo.215024
eb44deb2-976d-4240-ba61-7c68e9542905
1175-5326
215024
Culiseta kishenehn
,
sp. n.
(Figs 1, 2, 4A)
Adults
. Darkly ornamented mosquitoes, maxillary palpus, proboscis, legs (except ventral area of femora), wing and abdominal terga dark-scaled; proboscis slender, longer than forefemur; cell R2 longer than vein R2+3, tibiae and tarsi dark-scaled; base of hindcoxa below base of mesomeron; pulvilli absent or inconspicuous.
Female
.
Head
: Ornamentation of head capsule not evident; antenna
1.6–1.7 mm
, about 0.7 length of proboscis; maxillary palpus
0.3–0.5 mm
, 0.15−0.20 length of proboscis, with 4 palpomeres; proboscis
2.2−2.4 mm
, 1.3−1.5 length of forefemur, slightly to moderately bent ventrad (appearing straight in ventral view, specimen no. USNM 547066).
Thorax
: Black, ornamentation obscured.
Legs
: Femora without knee spots; forefemur
1.6–1.9 mm
, 0.7–0.8 length of proboscis; tibiae slightly swollen distally; ungues simple, fore- and midungues relatively large, equal, hindungues smaller, equal.
Wing
(Fig. 4A): Length
3.1–3.7 mm
(mean
3.3 mm
); base of subcosta with sparse(?) setae (radial setae of
Maslov, 1989
); distal half of wing with outstanding linear scales on most veins; vein R2 longer than vein R2+3 (R2/R2+3 = 1.7–2.0); base of vein M3+4 intersects M1+2 proximal to intersection of mediocubital crossvein with M1+2; anal vein (vein 1A) terminates well beyond intersection of mediocubital crossvein and cubitus.
Abdomen
: Apically rounded; terga entirely dark-scaled, no evidence of basolateral pale patches.
Genitalia
: Cerci short, rounded and scarcely visible; 3 spermathecal capsules.
Male
. Essentially as female.
Head
: Antenna about 0.7 length of proboscis; flagellomeres 1–11 each with whorl of very long dense setae, flagellomeres 12 and 13 very long, their combined length greater than total length of preceding flagellomeres; maxillary palpus longer than proboscis (1.1 times as long), comprised of 5 palpomeres, palpomeres 2 and 3 ankylosed, long, about 0.75 length of proboscis, palpomere 3 slightly swollen, bearing setae apically, palpomeres 4 and 5 not noticeably swollen, generally projecting straight forwards or turned slightly upwards, palpomere 4 and base of palpomere 5 with numerous long setae, remainder of palpomere 5 with some relatively short setae; proboscis about 1.4 length of forefemur.
Legs
: Ungues of fore- and midlegs enlarged, larger anterior unguis with proximal tooth; hindungues small, equal.
Abdomen
: Terga with well-developed setae along posterior margin.
Genitalia
: Prominent; gonocoxite elongate, relatively stout basally, gradually narrower toward apex, with crescentiform (ridge-like) basal mesal lobe (basal lobe of authors, gonofurca of
Maslov, 1989
) apparently bearing row(s) of setae on crest, no distinct apicodorsal lobe (apical lobe of authors); gonostylus borne at apex of gonocoxite, rather long and narrow, undivided; paraprocts of proctiger elongate, heavily sclerotized, with strong apical denticle.
Egg, larva and pupa
. Unknown.
Etymology.
The
Kishenehn
Formation is named for
Kishenehn
Creek.
Kishenehn
(American spelling) is a Kutenai Native American word meaning “no good”. Why the Kutenai adopted this name for the creek is unknown. The specific name
kishenehn
is understood to be masculine, but the evidence for usage as either a noun or an adjective is not decisive; consequently, it is regarded here to be a noun in apposition to the generic name of
Culiseta
, which is feminine.
Systematics
. In view of the importance of larval characters for recognizing the subgenera of
Culiseta
(
Edwards, 1932
;
Dobrotworsky, 1954
,
1960
,
1971
), it is not possible to place
Cs. kishenehn
in an extant subgenus. The weakly produced basal mesal lobe of the male genitalia is shared with species of subgenera
Culiseta
,
Climacura
Howard, Dyar & Knab
and
Culicella
Felt. The
origin of vein M3+4 proximal to the radiomedial crossvein (Fig. 4A,B), the entirely dark-scaled abdominal terga and the absence of an apicodorsal lobe on the gonocoxite of the male preclude the species from being placed in subgenus
Culiseta
, species which have the base of M3+4 more or less in line with the radiomedial crossvein, banded abdominal terga and an apicodorsal lobe on the gonocoxite. The distal position of the radiomedial crossvein relative to the origin of vein M3+4 and the absence of an apicodorsal lobe on the gonocoxite are characteristics of subgenera
Climacura
and
Culicella
. Subgenus
Climacura
includes five species in different parts of the world:
Cs. antipodea
Dobrotworsky
in southeastern
Australia
, the
type
species
Cs. melanura
(Coquillett)
in eastern North
America
,
Cs. tonnoiri
(Edwards)
and
Cs. novaezealandiae
Pillai
in
New Zealand
, and
Cs. marchettei
Garcia, Jeffery & Rudnick
in Southeast Asia.
Culiseta kishenehn
resembles these species, except the last one, in having entirely dark-scaled tarsi and abdominal terga, and also resembles
Cs. melanura
in having dark-scaled maxillary palpi, which are longer than the proboscis in males. It is not certain, but
Cs. kishenehn
seems to further resemble species of subgenus
Climacura
in having few subcostal setae (
Dobrotworsky, 1971
). Subgenus
Culicella
includes 14 species with distributions in
Australia
(seven species), North
America
(one species) and the Palaearctic Region (six species). Most of the species have banded tarsi and abdominal terga (three Australian species have unbanded terga and two of these have unbanded tarsi), but in most respects
Cs. kishenehn
seems to be more similar to species of subgenus
Climacura
. Considering the North American provenance of
Cs. kishenehn
and
Cs
.
melanura
, their close similarity in adult habitus is unlikely to be due to convergence.
Type
series.
Holotype
male (
USNM
no. 546528;
Kishenehn
no. 505.1), allotype female (
USNM
no. 546529,
Kishenehn
no. 610.4),
paratypes
males (
USNM
nos. 546530‒546533,
Kishenehn
nos. 624.1, 635.3, 686.1 and 693.1 respectively), Constenius Park (W 113° 42.085¢, N 48° 23.517¢),
paratype
female (
USNM
no. 546534,
Kishenehn
nos. 20093.1), Disbrow Creek (W 113° 40.999¢, N 48° 22.572¢) and
paratype
female (
USNM
no. 547066,
Kishenehn
no. 30624.1), Dakin (W 113° 42.173¢, N 48° 23.476¢),
Kishenehn
Formation, Montana,
USA
.
FIGURE 1.
Culiseta kishenehn
,
sp. n.
A,B.
Holotype
male (
USNM
546528), (A) head and its appendages, (B) genitalia (tergal aspect). C.
Paratype
male (
USNM
546530), body, maxillary palpi, proboscis and abdominal terga entirely dark-scaled. D.
Paratype
female (
USNM
546534), head with short maxillary palpus. E. Allotype female (
USNM
546529), distal part of left wing (dorsal) showing the projecting linear scales and long cell R2. BML = basal dorsomesal lobe; Ppr = paraproct; R2 = cell R2; R2+3 = vein R2+3.
FIGURE 2.
Culiseta kishenehn
,
sp. n.
A. Allotype female (
USNM
546529), habitus, appendages of head and thorax entirely dark-scaled (abdomen poorly preserved). B.
Paratype
female (
USNM
547066), abdomen (left side) and right wing (ventral), terga and wing entirely dark-scaled, long cell R2, apex of abdomen blunt. C.
Paratype
female (
USNM
546534), apex of abdomen showing the short cercus (partially obstructed by tergum VIII) and three spermathecal capsules. Ce = cercus; R2 = cell R2; SCa = spermathecal capsule; VIII-S = sternum VIII.
FIGURE 3.
Culiseta lemniscata
,
sp. n.
A,B. Holotype female (USNM 547065) and paratype female (USNM 546535) respectively, habitus, proximal portion of proboscis pale, legs and wings dark-scaled, abdominal terga with basal pale bands (arrows). C. Same as A, apex of abdomen showing the short cerci and three (indistinct) spermathecal capsules. Ce = cercus; SCa = spermathecal capsule; VIII-S = sternum VIII.
FIGURE 4.
A.
Culiseta kishenehn
,
sp. n.
Left wing of allotype female (
USNM
546529). B–D.
Culiseta lemniscata
,
sp. n.
B. Right wing (dorsal) of
holotype
female ((
USNM
547065). C,D. Same as B, (C) base of wing showing subcostal setae (actually on ventral surface), (D) distal portion of wing showing narrow semi-erect fusiform scales on post-costal veins. M2+3 = vein M2+3; rm = radiomedial crossvein; R2 = cell R2; R2+3 = vein R2+3; Sc = subcosta; SuS = subcostal setae.