Microphorella breviradia, sp. nov.
Creators: name: Cumming, Jeffrey M.
name: Brooks, Scott E.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Dolichopodidae
Microphorella
Microphorella breviradia

description: Microphorella breviradia sp. nov.
(Figs 1–4, 6, 7, 10–18, 22, 31, 32)
urn:lsid:zoobank.org:act: 586BABF9-B7D3-4B6B-8520-DD789B48DC44
Type material. HOLOTYPE ♂ labelled: “ USA: CA: El Dorado Co. / South Fork American River/ Eagle Rock river access / N38°46ʹ34.6ʺ W120°16ʹ00.7ʺ / 18.vii.2012, J.M. Cumming ”; “ CNC487253 [printed on both sides]”; “Legs removed/ for DNA/ analysis [green label]”; “HOLOTYPE/ Microphorella breviradia / Cumming & Brooks [red label]” (CNC). PARATYPES: USA: California: Same data as holotype except, CNC 487205, CNC 487212, CNC 487213, CNC 487217, CNC 487220, CNC 487225, CNC 487226, CNC 487229, CNC 487230, CNC 487231, CNC 487232, CNC 487234, CNC 487235, CNC 487236, CNC 487237, CNC 487238, CNC 487255, CNC 487256 (14♂, 4♀, CNC); same data except, S.E. Brooks, CNC DIPTERA # 192164, CNC DIPTERA # 192165, CNC DIPTERA # 192166, CNC DIPTERA # 192167, CNC DIPTERA # 192168, CNC DIPTERA # 192169, CNC DIPTERA # 192170, CNC DIPTERA # 192171, CNC DIPTERA # 192172, CNC DIPTERA # 192173, CNC DIPTERA # 192174, CNC DIPTERA # 192175, CNC DIPTERA # 192176, CNC DIPTERA # 192177, CNC DIPTERA # 192178, CNC DIPTERA # 192179, CNC DIPTERA # 192180, CNC 487206, CNC 487210, CNC 487211, CNC 487214, CNC 487215, CNC 487216, CNC 487218, CNC 487222, CNC 487224, CNC 487228, CNC 487239, CNC 487241, CNC 487242, CNC 487243, CNC 487244, CNC 487245, CNC 487246, CNC 487248, CNC 487249, CNC 487251, CNC 487252, CNC 487254, CNC 487271, CNC 487272, CNC 487274, CNC 487275, CNC 487276, CNC 487277, CNC 487278, CNC 487279, CNC 487280 (34♂, 14♀, CNC).
Other material examined. MEXICO: Baja California: Sierra San Pedro Martir NP [ca 31°00ʹN 115°33ʹW], 17 km E park entrance, 2900 m, 7.ix.1980, D.D. Wilder (2♂, 11♀, CAS); same data except, La Grulla, 6900 ft, 12.vi.1953, P.H. Arnaud, Jr (3♂, 3♀, CAS); same data except, Rancho Viejo, 7000 ft, 13.vi.1953 (2♂, CAS); same data except, 14.vi.1953 (1♀, CAS). USA: California: Alpine County: along Disaster Creek [ca 38°26ʹN 119°45ʹW], T7 N R20 E Sec. 26, 11.vii.1977, D.D. Wilder (15♂, 1♀, CAS); same data except, 11.vii.1977 (3♂, CAS); along Little Teton Creek [ca 38°22ʹN 119°49ʹW], T6 N R19 E Sec. 12, 12.vii.1977, D. Wilder (22♂, 16♀, CAS); El Dorado County: same data as holotype (176♂, 87♀, CNC); same data as holotype except, S.E. Brooks (203♂, 102♀, CNC); same data except, Eagle Rock Picnic Area, 38°46.58ʹN 120°16.01ʹW, 1384 m, sweep, 14.viii.1999, J. Savage (1♂, LEMQ); Fresno County: Sierra NF, along Pitman Crk, nr Big Crk [ca 37°12ʹN 119°13ʹW], 1500 m, T8 SR25 E Sec. 28, 2.viii.1979, D.D. Wilder (44♂, 63♀, CAS); Huntington Lake, Bolsillo Crk [ca 37°19ʹN 119°02ʹW], 10.vii.1984, J.F. MacDonald (1♂, CNC); Madera County: Chiquito Crk 0.25 mi. below Upper Chiquito Campground [ca 37°30ʹN 119°24ʹW], 6820 ft, 11.viii.1971, H.B. Leech (1♂, CAS); Mariposa County: Summerdale Forest Camp, on Big Creek [ca 37°29ʹN 119°38ʹW], 1520 m, 27.vi.1973, P.H. Arnaud, Jr (1♂, USNM); Mono County: Leavitt Meadows [ca 38°19ʹN 119°33ʹW], 2470 m, 23.vii.1966, P.H. Arnaud, Jr (3♂, 3♀, USNM); same data except, 25.vii.1966 (1♂, USNM); Riverside County: Idyllwild [ca 33°44ʹN 116°42ʹW], 7.vii.1940, A.L. Melander (1♂, USNM); San Jacinto Mountains, Black Mountain Creek, 11 km NW Idyllwild [ca 33°48ʹN 116°45ʹW], 1535 m, 1.vii.1968, P.H. Arnaud, Jr (3♂, 3♀, USNM); San Bernardino County: Crestline [ca 34°14ʹN 117°17ʹW], 4.vii.1942, A.L. Melander (2♂, USNM); same data except, 13.vii.1944 (1♂, USNM); S Fork Santa Ana River [ca 34°10ʹN 116°49ʹW], 16.vi.1945, A.L. Melander (1♂, 1♀, USNM); same data except, 19.vi.1945 (1♂, USNM); same data except, vic. Melander Cabin, 1950 m, 2.vii.1968, P.H. Arnaud, Jr (10♂, 7♀, CAS); Upper Santa Ana River [ca 34°10ʹN 116°49ʹW], 2.vii.1950, A.L. Melander (1♂, USNM); same data except, Lost Creek, 29.vii.1948 (1♀, USNM); San Diego County: Palomar Observatory Campground [ca 33°20ʹN 116°52ʹW], 25–27.vi.1968, P.H. Arnaud, Jr (1♀, CAS); same data except, 26.vi.1968, 1524 m (7♂, 5♀, USNM; 1♂, 2♀, CAS); same data except, 27.vi.1968, 1525 m (2♂, 1♀, USNM); Shasta County: W boundary Castle Crags SP [ca 41°08ʹN 122°19ʹW], 17.vii.1980, D.D. Wilder (95♂, 14♀, CAS); Montgomery Crk [ca 40°50ʹN 121°55ʹW], 2.viii.1970, P.H. Arnaud, Jr (2♂, 2♀, CAS); Siskiyou County: Klamath NF, East Fork Campground [ca 41°09ʹN 123°06ʹW], along E Fork of S Fork of Salmon R., 4.vii.1978, D.D. Wilder (2♂, CAS); Klamath NF, along Fish Lake Creek [ca 41°12ʹN 122°58ʹW], 21.vii.1980, D.D. Wilder (1♂, CAS); Klamath NF, along Portuguese Peak Trail [ca 41°22ʹN 123°23ʹW], T11 N R7 E Sec. 4, 2.vii.1978, D.D. Wilder (33♂, 9♀, CAS); Klamath NF, along first 2.5 mi. of Wooley Crk Trail [ca 41°22ʹN 123°25ʹW], T12 N R7 E Sec. 29 & 31, 3.vii.1978, D.D. Wilder (5♂, 7♀, CAS); Shasta Springs [ca 41°14ʹN 122°15ʹW], vii.1915, A.L. Melander (3♂, 1♀, USNM); Tehama County: Battle Creek Campground, South Fork Battle Creek [ca 40°20ʹN 121°37ʹW], 1460 m, 12.viii.1977, P.H. Arnaud, Jr (1♂, CAS); Tuolumne County: along Clark Fork River [ca 38°23ʹN 119°48ʹW], T6 N R19 E Sec. 14, 11.vii.1977, D. Wilder (11♂, 1♀, CAS); along Deadman Crk [ca 38°19ʹN 119°42ʹW], 8000 ft, 12.vii.1977, D. Wilder (5♂, CAS); Pinecrest [ca 38°11ʹN 119°59ʹW], 9.vii.1947, Acc. No. 258, P.H. Arnaud, Jr (6♂, 1♀, USNM); same data except, 15.vii.1947 (1♂, USNM); same data except, 1.viii.1947, Acc. No. 297 (1♀, USNM); same data except, 19.vii.1948 (16♂, USNM); same data except, 21.vii.1948 (1♂, USNM); same data except, 27.vii.1948 (1♂, USNM); Trinity County: Goldfield Campground, Boulder Creek [ca 41°06ʹN 122°46ʹW], 926 m, 15.viii.1980, P.H. Arnaud, Jr (1♂, USNM); Shasta NF, Boulder Creek nr Coffee Crk Rd [ca 41°06ʹN 122°46ʹW], 19.vii.1980, D.D. Wilder (2♂, CAS); Yosemite [ca 37°52ʹN 119°32ʹW], 13.vi.1935, A.L. Melander (1♂, USNM).
Problematic material examined. USA: California: San Bernardino County: 2.6 mi E of Seven Oaks, Santa Ana R., 34°11ʹ0.1ʺN 116°52ʹ12.1ʺW, 1770 m, 11.vi.2016, J.M. Cumming, CNC576977 (1♂, CNC, see “Remarks”); same data except, S.E. Brooks, CNC574674 (1♂, CNC, see “Remarks”); same data except, 11–12.vi.2016, YPT, Cumming & Brooks, CNC576726 (1♂, CNC).
Diagnosis. Males of M. breviradia sp. nov. are distinguished from those of M. macdonaldi sp. nov. and M. vespera sp. nov. by the following combination of features: narrow face (Fig. 2); right dorsal surstylar lobe with basiventral projection(s) (Figs 11, 12, 13); phallus long, tubular and C-shaped (Fig. 10). Males of M. breviradia sp. nov. are morphologically variable (see “Remarks”), compared to the known material of the other two species, and some specimens can be further distinguished by the following features: hind femur with ventral setae up to 2X femur width; hind tibia with short erect setae on anterior and ventral surfaces; right epandrial lamella elongated with anterior end subconical and strongly projected (Fig. 13). Females of M. breviradia sp. nov. appear to be indistinguishable from those of M. macdonaldi sp. nov. and M. vespera sp. nov.
Description. Male (Figs 1–4, 10–15): Body length 1.38–1.62 mm, wing length 1.43–1.67 mm. Head (Figs 1, 2): Largely blue-grey pruinose with dark brown to black ground colour; slightly broader than thorax in dorsal view, ovoid in lateral view; usually slightly broader than high in anterior view, wider in occasional specimens (about 1.3X broader than high); setae mostly black, paler on occiput laterally and on postgena ventrally. Ocellar triangle conspicuous. Vertex with greenish-bronze reflections. Occiput dark, concave on upper median part. Eyes covered with short ommatrichia, slightly longer near ventral margin; medial edge of eye with weak emargination adjacent to antenna; ommatidia of uniform size. Frons over 2X broader than high, widening above. Face narrow, about subequal to width of anterior ocellus at narrowest point in middle. Face and clypeus concolorous, grey pruinose. Clypeus not separated from face, as high as broad, apical margin weakly produced medially. Setae of head well differentiated: 1 pair of inclinate fronto-orbitals well-separated from base of antenna; 1 pair of lateroclinate anterior ocellars; 1 pair of small posterior ocellars; 1 pair of strong inclinate inner verticals (sometimes referred to as postocellars); 2–4 pairs of lateroclinate outer verticals, anterior and posterior pair usually stronger; upper postocular setae short and uniserial, longer and more scattered ventrally; postgena with longer scattered setae around edge of mouth-opening. Antenna entirely brown to dark brown, inserted above middle of head in profile; scape short, funnel-shaped; pedicel subequal in length to scape, spheroidal with subapical circlet of setulae; postpedicel elongate, 2.1–3.2X longer than wide, conical and gradually tapered distally to broader basally and more abruptly narrowed distally, clothed in fine setulae; arista-like stylus 1.2–1.7X length of postpedicel, with minute hairs. Palpus dark brown, short and narrow, slightly over 2X longer than wide, with 1–2 lateral setulae and 1 long preapical seta. Proboscis brown, short, projecting ventrally. Gena narrow. Thorax (Fig. 1): Dorsum pruinose, dull metallic blue-grey with strong greenish-bronze coloration on posterior 2/3–3/4 (including scutellum), to mostly bronze; pleura pruinose, dull metallic blue-grey with light metallic green and bronze reflections; setae black. Mesoscutum moderately arched, prescutellar depression present. Prosternum fused with proepisternum forming precoxal bridge. Proepisternum with a few setulae. Postpronotal lobe distinct with a few small setae. Mesonotum shield-shaped in dorsal view, slightly longer than wide. Acrostichal setae biserial, short, sometimes sparse, not extended onto prescutellar depression; other thoracic setae well differentiated, each side of mesonotum with: 6 dorsocentrals (posteriormost seta stronger), 1 strong presutural supra-alar (posthumeral), 3 postsutural supra-alars, sparse acrostichal-sized setae intermixed with supraalars, 2 strong notopleurals, 1 strong postalar. Scutellum broadly subtriangular with one strong seta per side. Mesopleuron bare. Halter pale brown. Legs (Fig. 1): Coxae dark brown to dark grey-brown and mainly concolorous with thorax; femora dark brown to dark grey-brown; trochanters, tibiae and tarsi dark brown; coxae with pale setae; trochanters, femora, tibiae and tarsi with brown to pale brown setae; setae of femora, tibiae and tarsi short, except hind femur with series of long ventral setae; tarsal claws, pulvilli and empodium normally developed on all legs. Foreleg: Coxa with anterior surface setose, apical setae longer; femur subequal in length to tibia; tibia with apical comb-like row of short setae on anterior surface; tarsus subequal in length to tibia; tarsomere 1 subequal to combined length of tarsomeres 2–4; tarsomeres 2–4 decreasing in length apically; tarsomere 5 somewhat enlarged, subequal to combined length of tarsomeres 3 and 4, broad, with short dorsal setae. Midleg: Coxa with 2 anterolateral setae and a few anterior setae along apical margin; femur subequal in length to tibia; tibia with relatively strong anteroapical seta; tarsus slightly to distinctly shorter than tibia, tarsomere 1 subequal to combined length of tarsomeres 2–5; tarsomeres 2–4 decreasing in length apically; tarsomere 5 slightly shorter than tarsomere 2. Hindleg: Coxa with 2 setae on lateral surface; femur slightly longer than tibia, with series of long pale to light brown ventral setae (longest setae up to 2X femur width in some specimens); tibia often slightly bowed outwardly, some specimens also with erect setae on anterior and ventral surfaces, with apical comb-like row of closely-spaced setae on posterior surface; tarsus distinctly shorter than tibia (about 0.6–0.7X tibia length); tarsomere 1 subequal to combined length of tarsomeres 2–4, tarsomere 2–4 gradually decreasing in length apically, tarsomere 5 subequal in length to tarsomere 3. Wing (Fig. 3): With brownish tinge, veins dark brown, about 2.4X longer than wide. Pterostigma absent, membrane entirely covered with minute microtrichia, alula absent. Costa circumambient. Extreme anterior base of costa with strong anterodorsal seta. Anterior section of costa (between base and R 4+5) bearing double row of spine-like setae, setae of ventral row stronger. Posterior section of costa (i.e. beyond R 4+5) with setae finer and longer. Longitudinal veins complete, reaching wing margin, except CuA+CuP (anal vein) extending halfway to wing margin, Sc faint apically. R 1 short, terminating before midpoint of wing. Base of Rs originating opposite humeral crossvein. R 2+3 subparallel with R 1 in basal 1/3, straight and parallel with R 4+ 5 in distal part. R 4+5 straight. M 1 nearly straight with gentle posterior curve apically. M 2 and M 4 nearly straight and subparallel beyond cell dm. Costal section between M 1 and M 2 longer than costal section between M 2 and M 4. CuA rounded. Short r-m crossvein present in basal portion of wing, distal to base of R 4+5. Crossvein bm-m incomplete. Cell dm present, closed by base of M 2 and dm-m crossvein, cell extending to middle of wing. Cells br, bm and cua in basal fourth of wing. Cells bm and cua broader than br. Cell cua closed, ovoid. Anal lobe not developed. Calypter with fine pale setae. Abdomen (Figs 1, 4, 10–15): Dark brown with grey tinge. Abdominal plaques usually visible on lateral margins of tergites and sternites 2–4; tergite 2 with transverse band of plaques visible anteriorly. Tergites 1–6 and sternites 2–5 with short setae along posterior surface (setae tiny on sternite 5), otherwise mostly bare, sternite 6 bare. Segment 7 bare. Segment 1 reduced and very short; segments 2–4 mostly symmetrical with simple tergites and sternites, segment 2 relatively long; segments 5–7 narrowed and laterally compressed to form cavity on right side for hypopygium. Sternite 5 with short broad ventral projection. Segment 7 tubular. Sternite 8 round and setose, forming dome-like cap over anterodorsal region of hypopygium (Fig. 14); tergite 8 narrow, U-shaped. Hypopygium (Figs 4, 10–15): Mainly dark brown. Lateroflexed to right, inverted with posterior end directed anteriorly, 1/3–1/2 length of abdomen, asymmetrical, foramen not formed. Epandrium divided into separate left and right lamellae. Left epandrial lamella (Fig. 10) trifurcate with surstylar lobes and ventral epandrial process projecting posteriorly, ventral edge fused with hypandrium but margin distinct. Left ventral epandrial process present, articulated at base, elongate, broadened in middle portion, narrowed apically with acute hooked apex, dorsal margin with pair of small setae near mid-length. Left surstylus bilobed with dorsal and ventral lobes separated by deep U-shaped cleft through which the left postgonite lobe protrudes (Fig. 10). Dorsal lobe of left surstylus large and broad (covering base of cercus), dorsal edge with concave basal emargination (Fig. 14) and rounded subapical protrusion bordering lateroventral margin of left cercus, apical margin rounded with several strong setae (Fig. 10), lacking prensiseta. Ventral lobe of left surstylus narrow, as long as dorsal lobe, with long apical seta and small seta below. Right epandrial lamella (Figs 4, 11–14) greatly enlarged, bowl-shaped, relatively short to elongate (compare Figs 11–13), comprising most of hypopygium in right lateral view; dorsal edge with broad concave emargination bordering lateroventral margin of right cercus; anterior end broadly rounded and weakly projected to subconical and strongly projected (compare Figs 11–13); posterior end with large dorsal surstylar lobe, small ventral surstylar lobe and ventral conical projection; fused with hypandrium along left margin (Fig. 10). Right ventral epandrial process absent. Right surstylus bilobed with dorsal and ventral lobes separated by cleft through which right postgonite lobe protrudes (Fig. 11). Dorsal lobe of right surstylus large and overlapping ventral lobe, dorsoapical margin rounded to broadly pointed with 3 strong submarginal setae, ventral margin with 1 or 2 basiventral projections and 3 strong marginal setae, lacking prensiseta. Ventral lobe of right surstylus short and broad, with a few marginal setae, mostly covered by dorsal lobe of surstylus. Hypandrium (Fig. 10) reduced to narrow subtriangular band, only visible from left side of hypopygium, with 2 tiny setae near apex. Postgonite with basal internal portion cradling base of phallus and ejaculatory apodeme; left and right postgonite lobes asymmetrical, protruding out from between dorsal and ventral lobes of surstylus. Left postgonite lobe (Fig. 10) narrow and strap-like, apex with narrow dorsal projection bearing a few small setae. Right postgonite lobe (Figs 10, 11, 14) large with expanded complex trilobate apex, bearing prominent thick seta near base of apical lobes. Phallus (Fig. 10) long and tubular, C-shaped, with very slender process medially on right side. Ejaculatory apodeme short and keel-like. Hypoproct (Figs 11, 14) projected as a pair of short asymmetrical lobes directly below cerci, left lobe short and globular with apical setae, right lobe longer and digitiform with apical setae. Cerci (Figs 11, 14, 15) asymmetrical; left cercus broad basally bearing 1 strong seta, with lateroventral margin fitting into dorsal concavity at base of dorsal surstylar lobe, distal portion narrowed and bent laterally, apex compressed laterally and rounded with pair of strong setae; right cercus broad basally bearing 1 strong seta, with lateroventral margin fitting into dorsal concavity near base of dorsal surstylar lobe, evenly tapered distally, with apex narrow (Fig. 14) or expanded and truncate (Fig. 15).
Female (Figs 16–18, 31, 32): Body length 1.19–1.67 mm, wing length 1.36–1.67 mm. Similar to male except as follows: Head: Face broader, nearly twice width of anterior ocellus at narrowest point in middle. Legs: Foreleg: Tarsomere 5 smaller with fewer dorsal setae. Midleg: Tarsus subequal in length to tibia. Hindleg: Femur with short indistinct setae ventrally; tibia straight, without erect setae; tarsus slightly shorter than tibia. Abdomen (Figs 31, 32): Tapering posteriorly, apical segments retractable into segment 7. Terminalia (Figs 16–18): Tergite 7 U-shaped and mostly desclerotized medially, with setae posteriorly, sternite 7 weakly sclerotized with setae posteriorly; tergite 8 medially divided, narrowly fused with sternite 8 anterolaterally; syntergite 9+10 medially divided into subrectangular hemitergites, with three acanthophorite setae on each side, widely separated from sternite 10; sternite 10 desclerotized medially; cercus ovoid with several rather long setae, apical seta longest; spermathecal duct unsclerotized, with broad, ridged sperm pump in basal part and textured spherical terminal expansion.
Distribution. This new species is known from northern California, USA south to Baja California, Mexico (Fig. 22).
Etymology. The species name refers to the short R 1 wing vein in both males and females, a feature shared by all three members of the M. breviradia species group.
Remarks. DNA barcode sequences were obtained and analyzed for 67 specimens (both males and females) of M. breviradia (Fig. 24). All were from the type locality of Eagle Rock, American River in central California (Figs 6, 7) and all clustered together with less than 2% genetic divergence from each other. However, these specimens, particularly males, exhibit considerable morphological variation in overall body size, width of the head, length of ventral setae on the hind femur, chaetotaxy of the hind tibia, and in the shape of the right epandrial lamella. This entire M. breviradia cluster appears to represent a morphologically variable species, which remains genetically separate from the M. vespera cluster (M. macdonaldi was not sequenced, see below). Two additional male specimens from Seven Oaks, southern California (CNC576977, CNC574674) that are sympatric (Figs 22, 23) and morphologically similar to M. breviradia, did not cluster with either M. breviradia or M. vespera, indicating that more sampling and sequencing is required to resolve whether these specimens should be included in this variable species concept or represent additional new cryptic species.
description: Published as part of Cumming, Jeffrey M. & Brooks, Scott E., 2022, Establishment of the Microphorella breviradia species group, with a key to the Nearctic species groups of Microphorella Becker (Diptera: Dolichopodidae sensu lato: Parathalassiinae), pp. 197-214 in Zootaxa 5134 (2) on pages 199-202, DOI: 10.11646/zootaxa.5134.2.2, http://zenodo.org/record/6536905