Microasydates santabarbara Gimmel and Mayor, 2022

Gimmel, Matthew L. & Mayor, Adriean J., 2022, Revision of Microasydates, New Nearctic Genus of Soft-Winged Flower Beetles (Coleoptera: Melyridae: Dasytinae: Listrini), The Coleopterists Bulletin 76 (4), pp. 537-568 : 557-559

3. Microasydates santabarbara Gimmel and Mayor , new species zoobank.org/ urn:lsid:zoobank.org:act:CD0E2A46-B202-4E5A-BCC2-1B0CB8EECD43 ( Figs. 2–4 , 7 , 9, 10 , 15 , 21, 22 , 27 , 31 , 36 , 40 , 46–49 , 55, 58, 61 , 62 , 64 , 65, 67 )

Type Specimen. Holotype ♂, deposited in SBMNH, labeled “USA: CA: Santa Barbara Co. \ Cold Spring Tr [ail] at Gibraltar Rd. \ 34.46743°N, −119.56898°W 590m \ 16Jul2015 ex Eri. confertiflorum \ coll. A.J. Mayor, M.&L. Gimmel // SBMNH \ ENT0119025 [blue label] // HOLOTYPE ♂ \ Microasydates \ santabarbara \ Gimmel & Mayor 2022 [red printed label]”.

Diagnosis. The body ( Figs. 7 , 9, 10 , 15 ) with at least mouthparts and legs pale yellow-orange, and with both pale and dark setae; pronotum with a sparse, loose fringe of elongate setae, some setae longer than the eye ( Figs. 21, 22 ); female pygidium deeply emarginate ( Fig. 36 ) and with a wide central glabrous area ( Fig. 40 ); median lobe of the aedeagus with three ventral teeth in addition to apical hook ( Figs. 46, 48 ; left proximal tooth hidden in Fig. 48 ); and a distribution including Santa Cruz, Santa Rosa, and Anacapa islands, and mainland Santa Barbara County distinguish M. santabarbara from all other species of Microasydates .

Description. Body ( Figs. 7 , 9, 10 , 15 ) medium-sized, elongate; weakly shining with slight bronze luster; head and pronotum with strong isodiametric microsculpture, sometimes somewhat reduced, elytra with microsculpture weak, particularly near apex. Length 2.09–2.63 mm (male mean: 2.23 mm; female mean: 2.34 mm); width 0.84–1.04 mm (male mean: 0.92 mm; female mean: 0.93 mm). Body uniformly black or dark brown dorsally, with antennae dark reddish-brown (scape and apical antennomeres blackish) and palps black; ventrally uniformly dark, except legs light reddish-brown with tarsomere 5 darkened apically, apex of abdomen around genital opening slightly lighter, and female sometimes with apical one-half of ventrite 5 light reddish-brown, rarely with apical 2–3 ventrites light reddish brown (some island specimens). Pubescence moderately dense, reclining over most of dorsal surface, sometimes reclining setae uniformly pale whitish or golden ( Fig. 9 ) or nearly uniformly dark, but more often with dark setae medially on the head, centrally on the pronotum, and two large, paired patches of dark setae on the elytra, one in the scapular region and the other larger and subapical, giving the appearance of sub-basal and marginal pale bands on the elytra ( Figs. 7 , 15 ); pronotal fringe ( Figs. 21, 22 ) consisting of sparse, semierect to erect setae, semierect setae pale and shorter, dark setae longer and erect, longer than diameter of eye in dorsal view, dark, erect setae extending in a dorsal row across anterior margin of pronotum ( Fig. 10 ); elytral fringe long, sparse, loose, mostly comprised of pale setae, with a few long, scattered dark, erect setae near humeral angle; ventral setae sparse to dense, uniformly pale and recumbent. Punctation nearly effaced on head and pronotum, moderately coarse and very dense on elytra, punctures separated by about one puncture diameter or less near elytral base where tending to line up transversely, forming weak transverse rugae, but becoming sparser apically. Head: Slightly enlarged in male, distinctly narrower than pronotum, eyes gently rounded laterally, weakly bulging; 1.48–1.59 times wider than interocular distance (male mean: 1.51; female mean: 1.52). Antennomeres 5–10 weakly serrate, antennomeres 6 and 8 somewhat reduced, antennomeres 9–11 more symmetrical; male antenna short, reaching to near basal one-fourth of pronotum posteriorly, female antenna slightly shorter. ThoraX: Pronotum ( Figs. 21, 22 ) wider than long, appearing weakly transverse, 0.74–0.78 times as long as wide (mean for both sexes: 0.76); widest at middle; lateral edges straight and diverging to middle in basal half, then straight and converging to anterior margin, not constricted, lateral bead weakly serrate; anterior angles obsolete, posterior angles weakly indicated but rounded. Elytra moderately elongate, broadly oval, more elongate in female, elytron 3.34–3.80 times as long as wide (male mean: 3.52; female mean: 3.59), elytra at humeri slightly wider than pronotum; elytral epipleuron in male wide for most of length, tapering abruptly at level of abdomen and disappearing at level of base of abdominal ventrite 5 ( Fig. 2 ), in female slightly narrower, disappearing at level of abdominal ventrite 4, lateral carina easily visible in dorsal view for entire length ( Fig. 7 ), slightly explanate; apical margin gently curved to suture, sutural angle distinct, often toothed, right-angled in female and slightly obtuse in male ( Fig. 27 ), margin strongly serrulate in both sexes. All tibiae with fine, pale setae along external margin; pro- and mesotibiae with very inconspicuous, short, slender and sparse dark spines arranged along external margin, spines more numerous and conspicuous in female; metatibia of male with distinct brush of dense, fine, black setae in apical one-third on inner margin ( Fig. 4 ), brush virtually absent in female. Abdomen: Male ventrites 3, 4, and 5 weakly depressed medially, with black spiculate setae primarily present in transverse field medially on ventrite 4 (very inconspicuous on the dark abdomen) ( Fig. 2 ), exceptionally black spiculate setae may be present on other ventrites up to ventrite 1. Pygidium of male with scattered sparse setae, glabrous in ill-defined basal triangle, with apex of pygidium truncate ( Fig. 31 ); female pygidium sparsely setose with wide median glabrous strip ( Fig. 40 ), apex with broad, distinct U-shaped emargination ( Fig. 36 ). Spiculum gastrale with basal strut short, distinctly less than one-half diameter of ring. Median lobe of aedeagus in lateral view ( Figs. 46, 48 ) with apical limb distinctly longer than basal limb, apex short, stout, strongly acute and sharply curved ventrally, ventral margin of apical limb with extremely proximate pair of ventrolateral teeth at same level (near proximal end of apical orifice) on a broad tubercle, plus with an additional, more distal unpaired tooth at level of middle of apical orifice and to the left of the midline, margin straight between unpaired tooth and apex; tegmen ( Figs. 47, 49 ) short, with weak or no constriction near base of ring. Female sternite VIII as in Fig. 58 ; spiculum ventrale shorter than width of sternite VIII ( Fig. 58 ); ovipositor as in Fig. 61 .

Etymology. This species is named after the city of Santa Barbara, California, the central vantage point for all major land masses where this species is known to occur. The name is to be treated as a noun in apposition.

Host Plant Associations. Adults of M. santabarbara have been collected from flowers of plants in the families Anacardiaceae , Apiaceae , Apocynaceae , Asteraceae , Brassicaceae , Convolvulaceae , Fagaceae , Liliaceae , Malvaceae , Namaceae , Papaveraceae , Plantaginaceae , Polygonaceae ( Fig.67 ), Rhamnaceae , Rosaceae , and Rubiaceae ( Table 1).

Seasonal Distribution. 7 June to 11 September ( Fig. 64 ).

Geographic Distribution. Known only from southwestern California in the Santa Ynez Mountains (up to an elevation of at least 1,200 m) (habitat in Fig. 65 ) and its foothills northwest to Vandenberg AFB, on Santa Cruz and Santa Rosa islands in Santa Barbara County, and from Anacapa Island, Ventura County ( Fig. 62 ). Despite a fair amount of collection effort by the authors in mountainous areas of mainland Ventura County during its season of adult activity, this species has not been observed there.

Paratypes (375). USA: CALIFORNIA: Santa Barbara County: Arroyo Hondo Preserve, 25 miles west of Santa Barbara, 34.486, −120.135, 2 July 2003, M. Caterino (1♂, SBMNH); Arroyo Hondo Preserve, 25 miles west of Santa Barbara, 34.486 8, −120.1366, 21 June 2004, on flowering Eriogonum, M. Caterino (1♂, SBMNH); Cold Spring Trail at Gibraltar Road, 34.467 43, −119.66898, 590 m, 16 July 2015, ex Malosma laurina, A. J. Mayor and M. and L. Gimmel (6♂♂, 9♀♀, SBMNH); same except ex Eriogonum fasciculatum (4♂♂, 5♀♀, SBMNH); same except ex Eriophyllum confertiflorum (6♂♂, 7♀♀, SBMNH); same except ex Hirschfeldia in- cana (1♀, SBMNH); same except ex Dendromecon rigida (1♀, SBMNH); same except 4 August 2019, ex Malosma laurina , M. and L. Gimmel and R. Leschen, ML341a (23♂♂, 33♀♀, SBMNH); same except ex Foeniculum vulgare, ML 341b (3♂♂, 4♀♀, SBMNH); same except ex Eriophyllum confertiflorum, ML 341c (1♀, SBMNH); same except ex Calystegia purpurata, ML 341d (6♂♂, 2♀♀, SBMNH); East Camino Cielo, 1 km east of Gibraltar Road, 34.491 26, −119.68196, 1,115 m, 10 June 2018, ex Eriodictyon crassifolium , M. and L. Gimmel, ML280b (2♂♂, 5♀♀, SBMNH); same except ex Prunus ilicifolia, ML 280c (1♂, SBMNH); same except ex Galium angustifolium, ML 280 (2♂♂, 1♀, SBMNH); same except ex Eriophyllum confertiflorum (1♂, SBMNH); East Camino Cielo near La Cumbre Peak, 34.494 47, −119.70674, 1,140 m, 4 August 2019, ex Eriogonum fasciculatum , M. and L. Gimmel and R. Leschen, ML342 (1♂, 2♀♀, SBMNH); along Gibraltar Road, 34.482 68, −119.68108, 840 m, 16 July 2015, ex Eriogonum fasciculatum, A. J. Mayor and M. and L. Gimmel (1♀, SBMNH); Gibraltar Road near Gibraltar Rock, 34.478 32, −119.68032, 805 m, 10 June 2018, ex Eriophyllum confertiflorum , M. and L. Gimmel, ML279a (1♂, 1♀, SBMNH); Santa Barbara, 3770 Foothill Road, 34.463 8, −119.7436, 215 m, 7 June 2016, ex Ceanothus, M. L. Gimmel and A. V. Evans, ML 91 (14♂♂, 21♀♀, SBMNH); Santa Barbara, lower edge coastal mountains, 29 July 1960, R. S. Beal (1♂, ASUHIC); Santa Ynez Mts. E. of Refugio Pass on Camino Cielo Rd., elev. 1,179 m, N34°31.864′, W119°59.583′, 18 July 2015, A. J. Mayor, collected beating flowers of Eriogonum fasciculatum (18♂♂, 12♀♀, UCRC); Toro Canyon Park, 34.436 01, −119.55470, 265 m, 21 July 2017, ex Malosma laurina , M. and L. Gimmel, ML218 (5♂♂, 8♀♀, SBMNH); same except ex Malacothamnus fasciculatus (1♀, SBMNH); same except ex Brassica nigra (1♂, SBMNH); Vandenberg AFB, Station Rd., Oak Mtn., UTM 10S 0730008 3826318, 23 July 2004, day coll. (3♂♂, 1♀, UCRC); same except 31 July 2005 (1♂ UCRC); same except Tranquillon Peak, 14 August 2004, leg. Pratt, Abela and Pierce, on Lithocarpus [= Notholithocarpus ] densiflorus (2♂♂, 2♀♀, UCRC); West Camino Cielo, 18 miles west-northwest of Santa Barbara, 34°31.4′N, 119°57.7′W, ~ 900 m, 4 July 2001, M. Caterino (1♀, SBMNH); West Camino Cielo, 1.6 km east of Refugio Road, 34.536 66, −120.05128, 795 m, 12 August 2018, ex Eriodictyon tomentosum , M. and L. Gimmel, ML296b (1♀, SBMNH); West Camino Cielo, 4.3 km east of Refugio Road, 34.533 82, −120.03413, 970 m, 12 August 2018, ex Eriogonum fasciculatum , M. and L. Gimmel, ML298 (1♀, SBMNH); West Camino Cielo, 4 miles east of Refugio Pass, 34.532 37, −120.01563, 1,015 m, 18 July 2015, ex Heteromeles arbutifolia, A. J. Mayor and M. L. Gimmel (2♂♂, SBMNH); West Camino Cielo, 5.5 miles east of Refugio Pass, 34.531 07, −119.99305, 1,200 m, 18 July 2015, ex Eriogonum fasciculatum, A. J. Mayor and M. L. Gimmel (5♂♂, 12♀♀, SBMNH); same except ex Eriodictyon traskiae (8♂♂, 14♀♀, SBMNH); same except ex Penstemon grinnellii (1♂, 1♀, SBMNH); Santa Cruz Island, 12 August 1939, Lloyd Martin, Los Angeles Museum Channel Islands Biological Survey, 1939-720 (2♂♂, 1♀, LACM); Santa Cruz Island, Central Valley, 22–29 June 1979, C. D. Nagano (4♂♂, 8♀♀, LACM); Santa Cruz Island, 12 August 1992, R. L. Doutt (1♂, 1♀, SBMNH); same except Central Valley, 8 June 1966, R. L. Langston (1♀, UCRC); same except 9 June 1966, ex Calochortus sp. (1♀, UCRC); same except Prisoner’s Harbor, 7 June 1966, J. Powell (3♂♂, UCRC); same except ex Asclepias sp. , R. L. Langston (1♀, UCRC); same except Ridge N. of Laguna Canyon, 8 June 1966, ex Heteromeles arbutifolia, R. L. Langston (1♂, UCRC); same except Upper Central Valley, 8 June 1966, R. L. Langston (1♀, UCRC); Santa Cruz Island, 4 June 2011, pan trap, 11880 (5♂♂, 6♀♀, EMEC); same except 11 September 2011, 11887, Santa Cruz Island Reserve (SCIR) Collection, 2017 (1♂, 1♀, EMEC); Santa Cruz Island, Site FSU, 10 June 2011, sample ID: hand collected ex morning glory, Santa Cruz Island Reserve (SCIR) Collection, 2017 (1♂, 1♀, UCSB); UC Santa Cruz Island Reserve, 33°59.617′N, 119°38.230′W, 11 September 2011, Cause Hanna (2♂♂, 4♀♀, SBMNH); same except Valley Anchorage, 33°59.288′N, 119°40.468′W, 11 September 2011, Cause Hanna (1♂, SBMNH); Santa Rosa Island, 5 August 1939, L. M. Martin (3♀♀, LACM); Ventura County: East Anacapa Island, 34.015 2, −119.3656, 26 June 2008, Chatzimanolis, Caterino and Polihronakis (6♂♂, 3♀♀, SBMNH).

Remarks. The color of the pubescence in M. santabarbara is variable, resulting in some distinctive patterns. In most of the Channel Island populations the dorsal setae are almost entirely pale, uniformly whitish or golden ( Fig. 9 ) with only a few long dark setae at the pronotal margins. Often, particularly in individuals from mainland populations in the Santa Ynez Mountains, the setal pattern is with dark setae medially on the head, centrally on the pronotum, and two large, paired patches of dark setae on the elytra, one in the scapular region and the other larger and subapical, giving the appearance of sub-basal and marginal pale bands on the elytra ( Figs. 7 , 15 ). In individuals from Vandenberg AFB the dark elytral setal markings merge, leaving the elytra with dark setae margined with a narrow pale band of whitish setae.

Figures

Figs. 1–4. Male characters of Microasydates, new genus. 1) M. umbratus, abdominal ventrites 1–5 in glycerol, ventral view. M. santabarbara, new species, SEMs: 2) Abdomen, ventral view showing spiculate setae concentrated on ventrite 4; 3) Tibiotarsal junction of middle leg showing acute, unmodified mesotibial spurs; 4) Hind leg showing subapical setal brush on metatibia and unmodified metatibial spurs.

Figs. 5–8. Dorsal habitus of male Microasydates, new genus. 5) M. punctipennis (SBMNHENT0080249); 6) M. sanclemente, new species (holotype; SBMNHENT0079371); 7) M. santabarbara, new species, patterned form; 8) M. umbratus, “umbratus” form (specimen from Shasta Co., CA). Scale bars = 1 mm.

Figs. 9–12. Habitus of male Microasydates, new genus showing variation. M. santabarbara, new species, unpatterned (island) form (specimen from Santa Cruz Island; SBMNHENT0108116): 9) Dorsal view; 10) Lateral view. 11) M. umbratus, “indigens” form, dorsal view; 12) M. umbratus, “testaceus” form, dorsal view. Scale bars = 1 mm.

Figs. 13–16. Dorsal habitus of female Microasydates, new genus. 13) M. punctipennis (LACMENT540887); 14) M. sanclemente, new species (SBMNHENT0079368); 15) M. santabarbara, new species; 16) M. umbratus. Scale bars = 1 mm.

Figs. 17–24. Pronota of Microasydates, new genus. M. punctipennis: 17) Male; 18) Female. M. sanclemente, new species: 19) Male; 20) Female. M. santabarbara, new species: 21) Male; 22) Female. M. umbratus: 23) Male; 24) Female.

Figs. 25–28. Elytral apices of male Microasydates, new genus. 25) M. punctipennis; 26) M. sanclemente, new species; 27) M. santabarbara, new species; 28) M. umbratus.

Figs. 29–32. Pygidia with attached sternite VIII of male Microasydates, new genus in glycerol. 29) M. punctipennis; 30) M. sanclemente, new species; 31) M. santabarbara, new species; 32) M. umbratus. Scale bars = 200 μm.

Figs. 35–37. Female pygidia of Microasydates, new genus in glycerol showing degree of apical emargination. 35) M. punctipennis; 36) M. santabarbara, new species; 37) M. umbratus. Scale bars = 200 μm.

Figs. 38–41. Female pygidia of Microasydates, new genus showing pubescence. 38) M. punctipennis;

Figs. 42–53. Median lobe (lateral view) and tegmen (ventral view) for male Microasydates, new genus in glycerol. M. punctipennis: 42) Median lobe; 43) Tegmen. M. sanclemente, new species: 44) Median lobe; 45) Tegmen. M. santabarbara, new species, specimen from Santa Ynez Mountains, CA: 46) Median lobe; 47) Tegmen. M. santabarbara, new species, specimen from Santa Cruz Island, CA: 48) Median lobe; 49) Tegmen. M. umbratus, specimen from Shasta Co., CA: 50) Median lobe; 51) Tegmen. M. umbratus, specimen from Juab Co., UT: 52) Median lobe; 53) Tegmen. Scale bars = 200 μm.

Figs. 54–61. Abdominal structures of female Microasydates, new genus in glycerol. Abdominal ventrites 4 and 5: 54) M. punctipennis; 55) M. santabarbara, new species; 56) M. umbratus. Sternite VIII with strut (spiculum ventrale): 57) M. punctipennis; 58) M. santabarbara, new species; 59) M. umbratus. Ovipositor: 60) M. punctipennis; 61) M. santabarbara, new species. Scale bars for Figs. 54–56 = 200 μm; for Figs. 57–61 = 500 μm.

Figs. 62–63. Distribution maps for species of Microasydates, new genus. 62) M. punctipennis (green squares), M. sanclemente, new species (red triangles), and M. santabarbara, new species (blue circles); 63) M. umbratus (black circles).

Fig. 64. Seasonalities of adult Microasydates, new genus species by month, based on collection records in the Specimens Examined sections.

Figs. 65–69. Habitats and flower hosts of adult Microasydates, new genus. 65) West Camino Cielo, Santa Ynez Mts., Santa Barbara Co., CA, July 2015 (habitat for M. santabarbara, new species and M. umbratus); 66) Yankee Canyon Dr. above Lake Isabella, Kern Co., CA, June 2018 (habitat for M. umbratus); 67) Eriogonum fasciculatum in Santa Barbara Co., CA, July 2015 (flower host for M. santabarbara, new species and M. umbratus); 68) Chrysothamnus viscidiflorus in Elko Co., NV, July 2018 (flower host for M. umbratus); 69) Trichostema lanceolatum in Stanislaus Co., CA, August 2017 (flower host for M. umbratus).