Cole, 1912 : 154
Revision of the Nearctic Parathalassius Mik (Diptera: Dolichopodidae: Parathalassiinae), with a review of the world fauna
Cumming, Jeffrey M.
Zootaxa
2017
2017-08-31
4314
1
1
64
4DF62
Cole
Cole. A
1912
[151,524,1153,1179]
Insecta
Dolichopodidae
Parathalassius
Animalia
Diptera
27
28
Arthropoda
species
melanderi
Parathalassius melanderi Cole, 1912: 154.
Type material examined. LECTOTYPE(here designated in order to fix identity of the species), ♂, from Laguna Beach [ca. 33°32′24″N 117°47′04″W], Orange County, California, USA, labelled: “Laguna Bch/ Cal. Cole [1912]”; “8”; “ Parathalassius/ melanderi/ n.sp. [red label]”; “LECTOTYPE/ Parathalassius/ melanderiCole/ des. Brooks & Cumming 2016[red label]” (USNM). PARALECTOTYPE: USA: California:same data as lectotype except, S. Cal. (1♂, EMEC). Our paralectotype label has additionally been attached to this specimen. Othermaterial examined. MEXICO: Baja California: Ensenada[ca. 31°50′06″N 116°36′39″W], 24.vi.1950, A.L. Melander( 2♂, 1♀, USNM); 10 mi. N El Rosario, El Consuelo Dunes[ca. 30°11′N 115°47′W], 24.iii.1979, J.D. Pinto, UCRC ENT 461757( 1♀, UCRC). USA: California: Orange County: Corona Del Mar[ca. 33°35′33″N 117°52′26″W], 19.xi.1946, A.L. Melander( 1♀, USNM); Crystal Cove State Park, 33°34′51.9″N 117°50′55.7″W, 6.vi.2016, swept sandy seacoast & beach vegetation, S.E. Brooks( 40♂, 59♀, CNC; 2♂, 2♀, CSCA); same data except, CNC574905, CNC574937( 2♂, barcoded, CNC), CNC574932, CNC574943( 2♀, barcode-associated, CNC); same data except, J.M. Cumming( 8♂, 22♀, CNC); same data except, CNC580763, CNC580778( 2♂, barcoded, CNC), CNC580779( 1♀, barcode-associated, CNC); same data except, S.H. Cumming( 1♀, CNC); Crystal Cove State Park, Pelican Point, moist sand in tidal zone, 6.viii.1993, H. Ulrich (2♀, ZFMK); same data except, 7.viii.1993( 1♂, 4♀, ZFMK); same data except, 8.viii.1993( 43♂, 13♀, ZFMK); same data except, 20.vii.1994( 8♂, 8♀, ZFMK); same data except, 21.vii.1994( 56♂, 10♀, ZFMK); Crystal Cove, 33°34.8'N 117°50.7'W, beach, 6.iv.2005, W.N. & D. Mathis( 9♂, 1♀, USNM); same data except, CNC478112( 1♀, barcode-associated); Laguna Beach[ca. 33°32′24″N 117°47′04″W], Cole( 2♀, EMEC); Doheny Park[ 33°27′42″N 117°40′56″W], 22.v.1944, A.L. Melander( 1♂, USNM); San Clemente State Beach, 33°24′18.7″N 117°36′22.8″W, 7.vi.2016, swept sandy seacoast, S.E. Brooks( 4♂, CNC); same data except, J.M. Cumming( 5♀, CNC); same data except, S.H. Cumming( 1♀, CNC); San Clemente, 23.v.1944, A.L. Melander( 1♂, USNM); San Diego County: Carlsbad[ca. 33°09′27″N 117°21′12″W], 22.vi.1950, A.L. Melander( 1♂, USNM); same data except, 24.vi.1954( 1♂, USNM); San Onofre State Beach, 33°22′29.3″N 117°34′04.7″W, 7.vi.2016, swept sandy seacoast, S.E. Brooks( 1♀, CNC); Silver Strand State Beach(east shore), 32°37′49.9″N 117°08′24.9″W, 8.vi.2016, swept sandy shore & beach vegetation, S.E. Brooks( 2♂, 2♀, CNC); Silver Strand State Beach, 4.viii.1993, H. Ulrich( 1♀, ZFMK); Santa Barbara County: Carpinteria[ca. 34°23′35″N 119°31′29″W], 23.ix.1946, A.L. Melander( 1♂, 1♀, USNM); Ventura County: San Nicolas Is., Dutch Harbor area[ca. 33°13′N 119°29′W], 6.v.1978, R. Coville( 3♂, 1♀, EMEC); same data except, J. Powell( 1♂, EMEC).
Diagnosis.This relatively small distinctive species is characterized by a short-subtriangular antennal postpedicel, longer lower male ommatrichia, 2 notopleural bristles, male with a wing darkened towards the apex, and female with slight infuscate shading along the wing veins near the apex of cell dm. Parathalassius melanderiis most similar to P. dilatus, but does not have male foretarsomeres 1–2 dilated.
Redescription. Male:Body length 2.3–2.9 mm, wing length 2.0– 2.2 mm. Dark brown ground colour covered mostly with dense greyish-white pruinosity. Setae of body and legs white. Head( Fig. 28): Eyes with ommatrichia of lower third distinctly longer and slightly flattened, forming dense reflective mat of whitish coloured hair. Face and clypeus concolourous with greyish-white frons and vertex. Face narrowest at middle, about 2.0–2.5X width of anterior ocellus. Gena and postgena with long white setae, forming distinct beard flanking mouthparts. Antenna ( Fig. 42) including arista-like stylus, entirely dark brown; postpedicel short-subtriangular, 1.35–1.45X longer than wide; arista-like stylus of medium length, about 1.5X length of postpedicel. Palpus with dense brush of 1 0–12 setae on outer surface of apical half. Thorax:Acrostichal setulae biserial; 6 dorsocentral bristles, 0 presutural intra-alar bristles, 1 presutural supra-alar (posthumeral) bristle, 2–3 postsutural supra-alar bristles, 2 notopleural bristles. Scutellum with 2–3 pairs of bristles. Legs: Foreleg: Dark grey, pale at knee and apex of tibia, tarsomeres 1–2 pale yellowish-brown, tarsomeres 3–5 brown to greyish-brown. Coxa with moderately long stout pale setae, densely covering anterior surface. Femur with moderately long setae on posterior surface, posteroventral rows prominent. Tibia with short setae and setulae. Tarsus with setulae; tarsomeres 1–2 not dilated. Midleg: Dark grey, pale at knee and apex of tibia, tarsomeres 1–2 pale yellowish-brown, tarsomeres 3–5 brown to greyish-brown, darker apically. Femur with anterodorsal setae most prominent, short. Tibia with pair of apicoventral bristles. Tarsomeres 1–4 each with several dark spine-like apicoventral setae. Hindleg: Dark grey, femur dark brown posteriorly, pale at knee and apex of tibia, tarsomeres 1–2 and base of tarsomere 3 pale yellowish-brown, apex of tarsomere 3 and tarsomeres 4– 5 brown to greyish-brown, darker apically. Femur with anteroventral row of setae most prominent, short basally, longer apically. Tibia clothed with short setae. Tarsus longer than tibia with short setae and setulae; tarsomere 1 long, but shorter than combined length of tarsomeres 2–4; tarsomeres 1–4 lacking peg-like or thickened setae dorsally; tarsomere 2 long, longer than tarsomere 3; tarsomere 3 long, longer than tarsomere 4; tarsomere 4 longer than tarsomere 5. Wing( Fig. 60): Lightly infuscate apically, hyaline basally, with yellowish veins basally and dark brown veins apically. Cell dm slightly produced apically, dm-m crossvein nearly straight. Vein CuA+CuP short to medium length, straight. Abdomen:Tergites 2–4 with setae well-developed. Sternite 5 without projecting pregenitalic process, posterior edge of sternite deeply emarginate. Sternite 8 subquadrate with setae longer along posterolateral margins. Hypopygium( Figs 86, 99–100, 125): Large. Left epandrial lamella with ventral portion elongate (about 2Xlonger than high); ventral epandrial process broadly bifurcate, dorsal arm elongate and strongly curved ventrally, more or less evenly slender, apex slightly expanded dorsally and prominently hook-like, ventral arm thick with minute apicodorsal seta and pair of minute setae along distiventral margin, apex with expanded lamelliform concavity. Dorsal lobe of left surstylus subtriangular, with basiventral edge broadly rounded, apex pointed, with long basidorsal seta, short lateral seta and long apical seta, medial surface with knob-like projection bearing lamelliform apical process. Ventral lobe of left surstylus shallowly bilobate in lateral view, dorsal lobe short with apex rounded, ventral lobe with rounded base bearing short lateral seta and complex upturned bifurcate projection arising medioventrally. Right epandrial lamella with ventral epandrial process spur-like; basal portion of epandrial lamella narrowed and dorsally curved, with deep dorsal emargination bordering ventral margin of right cercus. Dorsal lobe of right surstylus with 3 lateral setae (lowermost seta weaker), apex narrowed with rounded tip bearing thick apically-frayed prensiseta on medial surface. Ventral lobe of right surstylus recurved at base with lateral seta near middle, with elongate finely-tipped process proximal to narrow apex. Hypandrium very large, elongate-reniform with convex anterior and posterior ends extending to or beyond margins of epandrial lamellae in lateral view, bare. Left postgonite lobe ovoid basally, constricted near middle, distal portion subrectangular and flat without claw-like apical process, base of lobe with broad curved apically-pointed medial projection. Right postgonite lobe with broad lateral protuberance pointed at apical margin and lamelliform medial projection, apex bifurcate with short digitiform process and rounded lamelliform process. Phallus short and weakly curved, basal portion broad with ventral flange, gradually tapering distally, lacking dorsal flange and left lateral protuberance at 2/3 length. Ejaculatory apodeme broadly subtriangular. Hypoproct strongly projected dorsally as pair of acutely pointed subtriangular lobes, each lobe with 3 preapical ventral setae, lower seta strong, left lobe with piliferous flange lateral to lower seta. Cerci with anal setae well-developed and differentiated from surrounding hairs; right cercus much larger than left cercus with basal portion distended and rounded laterally, apex weakly deflected dorsally, truncate with pair of setae along apicolateral margin; left cercus oblong-subrectangular in dorsal view, apex even with apex of right cercus, weakly deflected dorsally, broadly pointed with pair of apical setae. Female:Body length 2.4–3.0 mm, wing length 2.1–2.4 mm. Similar to male except as follows: Head:Eyes with ommatrichia of nearly uniform length, not distinctly longer on lower third. Face wider, at middle about 4.0– 4.5X width of anterior ocellus. Palpus less densely setose. Legs: Foreleg: Coxa with slightly shorter more slender setae on anterior surface. Wing( Fig. 61): Hyaline, with (in most specimens) slight infuscate shading along veins near apex of cell dm. Abdomen:Tergite 5 broadly subtriangular to semicircular in dorsal view with posterior margin rounded (cf. Fig. 131). Terminalia distinctly narrower than base of segment 5 (cf. Figs 131–132); sternite 8 trough-like, lacking basal bulge, not narrowed apically, apical half without longitudinal ridges, apex emarginate ( Fig. 136); sternite 9 reduced to narrow weakly-developed transverse sclerotized band; tergite 10 with hemitergites subtriangular and short, each with 2 acanthophorite spines; cercus short, blunt-tipped.
Distribution and seasonal occurrence. Parathalassius melanderiis currently known to occur on sandy seashores from Carpinteria in Southern California, south to El Consuelo Dunes, near El Rosario in Baja California( Fig. 147). Adults have been collected from late March to mid November.
Remarks.A large series of P. melandericollected at Crystal Cove State Park in southern California( Fig. 21) exhibited a behavioural change depending on the time of day. Early in the day, from morning through to mid afternoon, a few adult flies (both males and females) were collected on open dry or wet sand near the ocean, but apparently nowhere else. After 6:30 pm however, flies were no longer found on this part of the beach, but numerous individuals (both males and females) were taken further away from the ocean, on vegetation bordering the beach ( Fig. 22).
1587280117
1950-06-24
USNM
A. L. Melander
Mexico
31.835001
Ensenada
20
-116.61083
Other
27
28
3
1
2
MEXICO
1587280130
1979-03-24
UCRC
J. D. Pinto
Mexico
30.183332
El Consuelo Dunes
1223
-115.78333
El Rosario
27
28
ENT 461757
1
1
MEXICO
1587280125
1946-11-19
USNM
A. L. Melander
United States of America
Orange County
33.5925
Corona Del Mar
19
-117.87389
27
28
1
1
California
1587280137
2016-06-06
CNC, CSCA
S. E. Brooks
United States of America
33.58108
Crystal Cove State Park
1
-117.84881
27
28
103
61
42
California
1587280127
2016-06-06
CNC
S. E. Brooks
United States of America
33.58108
Crystal Cove State Park
1
-117.84881
27
28
CNC574905, CNC574937, CNC574932, CNC574943
4
2
2
California
1587280121
[465,1059,1722,1747]
2016-06-06
CNC
J. M. Cumming
United States of America
33.58108
Crystal Cove State Park
1
-117.84881
27
28
30
22
8
California
1587280135
2016-06-06
CNC
J. M. Cumming
United States of America
33.58108
Crystal Cove State Park
1
-117.84881
27
28
CNC580763, CNC580778, CNC580779
3
1
2
California
1587280131
2016-06-06
CNC
S. H. Cumming
United States of America
33.58108
Crystal Cove State Park
1
-117.84881
27
28
1
1
California
1587280134
[253,790,1830,1855]
1993-08-07
ZFMK
S. H. Cumming
United States of America
33.58108
Crystal Cove State Park
1
-117.84881
27
28
5
4
1
California
1587280116
[802,1367,1830,1855]
1993-08-08
ZFMK
S. H. Cumming
United States of America
33.58108
Crystal Cove State Park
1
-117.84881
27
28
56
13
43
California
1587280129
1994-07-20
ZFMK
S. H. Cumming
United States of America
33.58108
Crystal Cove State Park
1
-117.84881
27
28
16
8
8
California
1587280151
[665,1261,1866,1891]
1994-07-21
ZFMK
S. H. Cumming
United States of America
33.58108
Crystal Cove State Park
1
-117.84881
27
28
66
10
56
California
1587280133
2005-04-06
USNM
W. N. & D. Mathis
United States of America
33.58
Crystal Cove
120
-117.845
27
28
10
1
9
California
1587280136
2005-04-06
EMEC
Cole
United States of America
33.54
Laguna Beach
20
-117.78445
27
28
CNC478112
3
3
California
1587280123
1944-05-22
USNM
A. L. Melander
United States of America
33.461666
Doheny Park
20
-117.68222
27
28
1
1
California
1587280140
2016-06-07
CNC
S. E. Brooks
United States of America
33.405197
San Clemente State Beach
1
-117.60633
27
28
4
4
California
1587280143
[804,1314,2010,2035]
2016-06-07
CNC
J. M. Cumming
United States of America
33.405197
San Clemente State Beach
1
-117.60633
27
28
5
5
California
1587280171
2016-06-07
CNC
S. H. Cumming
United States of America
28
29
33.405197
San Clemente State Beach
1
-117.60633
27
28
1
1
California
1587280149
[567,1203,151,176]
1944-05-23
USNM
A. L. Melander
United States of America
San Clemente
28
29
1
1
California
1587280166
1950-06-22
USNM
A. L. Melander
United States of America
San Diego County
33.1575
Carlsbad
20
-117.35333
28
29
1
1
California
1587280168
1954-06-24
USNM
A. L. Melander
United States of America
San Diego County
33.1575
Carlsbad
20
-117.35333
28
29
1
1
California
1587280165
2016-06-07
CNC
S. E. Brooks
United States of America
33.374805
San Onofre State Beach
1
-117.56797
28
29
1
1
California
1587280159
2016-06-08
CNC
S. E. Brooks
United States of America
32.630527
Silver Strand State Beach
1
-117.14025
28
29
4
2
2
California
1587280153
1993-08-04
ZFMK
H. Ulrich
United States of America
Silver Strand State Beach
28
29
1
1
California
1587280182
1946-09-23
USNM
A. L. Melander
United States of America
Santa Barbara County
34.39306
Carpinteria
19
-119.52473
28
29
2
1
1
California
1587280139
1978-05-06
EMEC
R. Coville
United States of America
Ventura County
33.216667
Dutch Harbor area
1206
-119.48333
San Nicolas Is.
28
29
4
1
3
California
1587280154
[302,766,404,429]
1978-05-06
EMEC
J. Powell
United States of America
Ventura County
33.216667
Dutch Harbor area
1206
-119.48333
San Nicolas Is.
28
29
1
1
California