Asydates vandykei ( Blaisdell, 1924 ), CA, 2019

Mayor, Adriean J. & Gimmel, Matthew L., 2019, Revision of the Soft-Winged Flower Beetles of the Genus Asydates Casey, 1895 (Coleoptera: Melyridae: Dasytinae: Listrini), The Coleopterists Bulletin (mo 17) 73, pp. 1-71 : 25-40

9. Asydates vandykei ( Blaisdell, 1924) , new combination

( Figs. 5A–B , 9A–B , 12E–F , 16E–F , 22C , 27A–D , 29C , 31A , 38B , 40 , 47 )

Pristoscelis vandykei Blaisdell 1924b: 15–16 . Holotype, male, from “Irvington, Alameda County, California ”, CAS type #2669, examined. Leng and Mutchler 1927: 27 (catalog); Pic 1937: 90 (catalog).

Pristocelis [sic] vandykei: Howell 1979: 45, 1997: 12 .

Scelopristis vandykei: Mayor 2004: 86 .

Type Material. Holotype ♂ ( Fig. 47 ), Pristoscelis vandykei , deposited in CAS, labeled “Irvington \Alameda \Co. CAL. \ix – 00 [white printed label] //E C Van Dyke \Collector [white printed label] //Blaisdell \Collection [grey printed label] // Holotype ♂ \vandykei \ Blais [red handwritten label] // California Academy \of Sciences \Type No. 2669 [white printed and handwritten label] // Type ♂ \ Pristoscelis \vandykei \Blais. [red and white handwritten label]”.

Diagnosis. The dorsal surface of the elytra with pale reclining setae, the setal fringe of the pronotum lacking long projecting setae ( Fig. 16E–F ), male abdominal ventrite 1 with a much less distinct median patch of dense pale setae, and the median lobe of the aedeagus with a ventrally curved apex ( Fig. 27A–D ) distinguish A. vandykei from all other species of Asydates .

Redescription. Body elongate, moderately robust, shiny, head and pronotum with dense, inconspicuous microsculpture, elytra with sparse, inconspicuous microsculpture ( Figs. 5A–B , 9A–B ). Length 2.6 mm (2.1–3.2 mm, n = 36); width 1.1 mm (0.8–1.45 mm, n = 36). Head, pronotum, elytra, antennomeres 5–11, and venter black; legs, pygidium, male ventrite 5, and all female ventrites orange; elytral apex narrowly pale or not; rarely, elytra orange with a small, black, V-shaped basal macula. Pubescence sparse, reclining, pale, whitish to golden; pronotal fringe short, not projecting. Punctation with punctures fine, indistinct on head, pronotum, and elytra. Head: Slightly enlarged, narrower than pronotum, eyes bulging ( Fig. 12E–F ); 1.57 (1.45–1.70, n = 36) times wider than interocular distance. Antennomeres 5–10 weakly serrate; male antennae short, reaching to near basal quarter of pronotum posteriorly, female antennae shorter. Thorax: Pronotum wider than long, 0.75 (0.70–0.83, n = 36) times as long as wide; widest at middle; lateral edges converging to anterior margin, slightly constricted before anterior margin; anterior and posterior angles obsolete, broadly rounded ( Fig. 16E–F ). Elytra elongate, broadly oval, elytron 3.54 (3.05–4.17, n = 36) times as long as wide, at humeri slightly wider than pronotum; elytral epipleuron distinct at base, becoming obsolete near apex of abdominal ventrite 4 in both sexes; apical margin broadly rounded to weak sutural angle, margin weakly serrulate in both sexes. All tibiae with fine, white setae along external margin; pro- and mesotibiae with numerous short, stout, widely placed spines arranged along external margin in both sexes. Abdomen: Male ventrite 1 with indistinct median patch of white setae. Pygidium ( Fig. 22C ) unmodified in male, with a straight hind margin, apex broadly rounded in female. Median lobe of aedeagus a bowed tube with apex directed slightly ventrally ( Fig. 27A–D ); tegmen relatively short and wide, with slight constriction at base of ring ( Fig. 29C ).

Host Plant Associations. Adults of A. vandykei have been collected from the flowers of plants in the families Asteraceae [ Ericameria arborescens (1), Eriophyllum confertiflorum (1), Stephanomeria cichoriacea (3), S. pauciflora (15), S. virgata (67), and Stephanomeria sp. (61)], Brassicaceae [ Brassica nigra (3), Hirschfeldia incana (1)], Loasaceae [ Mentzelia laevicaulis (1)], and Polygonaceae [ Eriogonum elongatum (28), E. fasciculatum (77), E. nudum (44), E. roseum (23) ( Fig. 31A ), and Eriogonum sp. (6)].

Seasonal Distribution. 6 July to 27 October ( Fig. 40 ).

Geographic Distribution. Known from the southern Coast Ranges from Irvington (types) in Alameda County south to the western Transverse Ranges in Santa Barbara and Ventura Counties ( Fig. 38B ) .

Material Examined. Records reported here are based on the examination of 345 specimens. USA: CALIFORNIA: Alameda County: [label indicates county only]/ E. C. Van Dyke Collector (2♀♀, CAS) ; same except feeds on wild buckwheat (1♂, CAS); Irvington , ix-00, E. C. Van Dyke collector (holotype ♂, paratypes, 3♀♀, CAS) ; Fresno County: Monocline Ridge, Monvero Dunes , el. 328 m, 27 Aug. 2014, N36°32’13”, W120°33’42”, on Eriogonum, G. R. Ballmer (3♂♂, 3♀♀, UCRC) ; Monterey County: Nacimiento-Fergusson Road between Nacimiento & Ponderosa campgrounds, 36.00443°, -121.39064°, 480 m, 19 August 2018, ex Eriogonum roseum , M. & L. Gimmel, N. Rasmussen, ML305 (11♂♂, 10♀♀, SBMNH, 1♂, 1♀, UCRC) ; along Lockwood-San Lucas Road , 36.00364°, -121.06731°, 455 m, 19 August 2018, ex Stephanomeria virgata , M. & L. Gimmel, N. Rasmussen, ML306 (24♂♂, 31♀♀, SBMNH, 1♂, 1♀, UCRC) ; same except ex Brassica nigra (2♂♂, 1♀, SBMNH) ; San Benito County: Idria, 10 mi. N. ( Gem Mine ), vii-17, 1959, M Wasbauer, Eriogonum inflatum (1♂, EMEC) ; San Luis Obispo County: 7 mi. E. of Cholame , 18 July 1956, K. S. Hagen (5♂♂, 1♀, EMEC) ; Santa Barbara County: Cold Spring Trail at Gibraltar Road , 34.46743°, -119.66898°, 590m, 15 July 2015, on Hirschfeldia incana , A.J. Mayor, M. & L. Gimmel (1♀, SBMNH) ; same except ex Eriophyllum confertiflorum (1♀, SBMNH) ; Sunset Valley Road, 34.74931°, -119.92655°, 840 m, 3 September 2015, ex Ericameria arborescens , M. & L. Gimmel (1♀, SBMNH) ; Figueroa Mountain Road near Grass Mountain , 34.74311°, -120.04453°, 675 m, ex Stephanomeria , 3 September 2015, leg. M. & L. Gimmel (1♀, SBMNH) ; along Happy Canyon Road , 34.66579°, -119.93798°, 420 m, 6 September 2017, ex Stephanomeria , M. & L. Gimmel, ML250 (3♂♂, 1♀, SBMNH) ; upper Happy Canyon Road , 34.72151°, -119.91743°, 875 m, 27 October 2018, ex Stephanomeria virgata , M. & L. Gimmel, ML310 (5♂♂, 5♀♀, SBMNH) ; Pinery Road at Figueroa Mountain Road, 34.72692°, -119.94944°, 1 330 m, 6 September 2017, ex Stephanomeria , M. & L. Gimmel, ML251 (13♂♂, 24♀♀, SBMNH) ; Refugio Road 14 km N of Hwy 101, 34.51206°, -120.06920°, 210 m, 12 August 2018, ex Eriogonum elongatum , M. & L. Gimmel, ML295 (16♂♂, 11♀♀, SBMNH) ; West Camino Cielo 4.3 km E of Refugio Road, 34.53382°, -120.03413°, 970 m, 12 August 2018, ex Stephanomeria , M. & L. Gimmel, ML298 (6♂♂, 13♀♀, SBMNH) ; East Camino Cielo , 3.4 km E of Hwy 154, 34.51896°, -119.78360°, 970 m, 3 September 2018, ex Stephanomeria cichoriacea , M. & L. Gimmel, ML307 (2♂♂, 1♀, SBMNH) ; same except ex Eriogonum elongatum (1♂, SBMNH) ; Vandenberg AFB, Station Rd., Oak Mt. , 08/13/04, leg. Abela, Pierce & Pratt (1♂, UCRC) ; Santa Clara County: Arroyo Bayo, E. base of Mt. Hamilton , 21 August 1962, J. Powell (1♀, EMEC) ; Ventura County: Cuyama River on Hwy. 33, elev. 991 m, N34°46’11.2”, W119°25’18.9”, 1 August 2017, A. J. Mayor, collected beating flowers of Stephanomeria pauciflora (5♂♂, 10♀♀, UCRC) ; Los Padres Natl. Forest, Hwy. 33, 2.5 mi. N. of Wheeler Springs , el. 623 m, N34°31’11.2”, W119°16’31.3”, 20 July 2016, A. J. Mayor, collected beating flowers of Eriogonum fasciculatum (2♂♂, UCRC, 1♂, SBMNH) ; same except 31 July 2016 (1♂, UCRC, 1♂, SBMNH) ; same except elev. 589 m, N34°31’11.3”, W119°16’31.5”, 6 July 2017, A. J. Mayor, collected beating flowers of Eriogonum fasciculatum (29♂♂, 27♀♀, UCRC) ; Pine Mountain Summit on Hwy. 33, elev. 1,457 m, N34°38’58.1”, W119°23’7.2”, 6 July 2017, A. J. Mayor, collected beating flowers of Eriogonum fasciculatum (1♂, 1♀, UCRC) ; N. of Pine Mountain Summit on Hwy. 33, elev. 1,490 m, N34°39’27.4”, W119°22’55.0”, 6 July 2017, A. J. Mayor, collected beating flowers of Eriogonum fasciculatum (8♂♂, 6♀♀, UCRC) ; same except collected beating flowers of Eriogonum nudum (19♂♂, 12♀♀, UCRC) ; same except elev. 1,501 m, N34°39’26.7”, W119°22’54.7”, 1 August 2017, A. J. Mayor, collected beating flowers of Eriogonum nudum (4♂♂, 9♀♀, UCRC) ; Rose Valley Road above Gun Club , 34.54755°, -119.18098°, 1,050 m, 12 August 2016, ex Mentzelia laevicaulis , M. & L. Gimmel, ML109 (1♂, SBMNH) .

Remarks. Asydates vandykei is more variable than most other species of Asydates . This variation is expressed in differences in size, as well as differences in coloration. In general, populations from the northern part of its range are larger than those from the southern part. Also, in most populations, the elytra are black with the apex narrowly orange or not. However, in specimens from the Monvero Dunes in western Fresno County, the elytra are orange with a small, black V-shaped basal macula. The median lobe of the aedeagus has a slightly different shape in the Monvero Dunes population, with the apex slenderer and more elongate ( Fig. 27B ). However, based on our observations to date within the genus, this modest level of variation is not sufficient for recognition of a species distinct from A. vandykei . Samples of geographically intermediate populations between the Monvero Dunes and other previously sampled populations would be required to fully explore this issue.

1.0 mm.

Asydates vandykei appears to be most closely related to A. ruficauda . Specimens of A. vandykei are larger, more robust, and the median patch of white setae on male abdominal ventrite 1 is inconspicuous and not well developed, while in the smaller, more graciliform individuals of A. ruficauda the patch of white setae on male abdominal ventrite 1 is conspicuous ( Fig. 19B ). There are also differences in the shape of the aedeagus. In individuals of A. ruficauda , the body of the median lobe of the aedeagus is sharply bent at a 90° angle, while the apex is conspicuously bent ventrally at a

A. rufiventris : E) Male, F) Female Fig. 11. irwini , E) Male Asydates species , frontal view. A. chumash : A) Male, B) Female. A. tongva : C) Male, F) Female. Scale bars = 1.0 mm.

, D) Female. A. vandykei : E) Male, F) Female. Scale bars = 1.0 mm.

inexpectatus : E) Male. Scale bars = 1.0 mm.

rufiventris : E) Male, F) Female.

E) Male, F) Female.

nearly 90° angle ( Fig. 26A–D ); in individuals of A. vandykei , the body of the aedeagus is more smoothly and shallowly bent, while the apex is only slightly bent ventrally ( Fig. 27A–D ).

Figures

Fig. 5. Asydates species, dorsal habitus. A. vandykei: A) Male, B) Female. A. washoe: C) Male, D) Female. Scale bars = 1.0 mm.

Fig. 9. Asydates species, lateral habitus. A. vandykei: A) Male, B) Female. A. washoe: C) Male, D) Female. A. phantasma: E) Male, F) Female. A. inexpectatus: G) Male. Scale bars = 1.0 mm.

Fig. 12. Asydates species, frontal view. A. shoshone: A) Male, B) Female. A. ruficauda: C) Male, D) Female. A.

Fig. 16. Asydates species, pronota. A. shoshone: A) Male, B) Female. A. ruficauda: C) Male, D) Female. A. vandykei: E) Male, F) Female.

Fig. 22. Asydates species, male pygidium and attached abdominal sternite VIII, ventral view. A) A. irwini, B) A. ruficauda, C) A. vandykei (spiculum gastrale is still attached), D) A. inexpectatus. Scale bars = 0.5 mm.

Fig. 27. Asydates species, median lobe of aedeagus, right lateral view. A. vandykei: A) CA: Alameda Co.: Irvington, B) CA: Fresno Co.: Monvero Dunes, C) CA: Ventura Co.: Highway 33 near Wheeler Springs, D) CA: Ventura Co.: Highway 33 near Wheeler Springs. E) A. phantasma, UT: Emery Co.: Woodside. Scale bars = 0.5 mm.

Fig. 29. Asydates species, tegmen of aedeagus (apex directed upward). A) A. shoshone, NV: Elko Co.: 43.5 km south of Wells, B) A. ruficauda, CA: Inyo Co.: Westgard Pass Road, C) A. vandykei, CA: Alameda Co.: Irvington, D) A. washoe, NV: Lyon Co.: 7.2 km south of Sweetwater Summit on Highway 338, E) A. phantasma, UT: Emery Co.: Woodside, F) A. inexpectatus, CA: San Bernardino Co.: 1.6 km north of Hodge. Scale bars = 0.5 mm.

Fig. 31. Habitat for Asydates species. A) Open hillside along Nacimiento-Fergusson Road, Monterey Co., CA, habitat of A. vandyeki collected from flowers of Eriogonum roseum. Photograph taken 19 August 2018 by Matthew L. Gimmel. B) Steep valley along Middle Fork Lytle Creek in the San Gabriel Mountains in San Bernardino Co., CA, habitat of A. tongva collected from flowers of Stephanomeria pauciflora. Photograph taken 25 July 2017 by Adriean J. Mayor.

Fig. 38. Distribution of Asydates species. A) Localities of examined specimens of A. ruficauda, B) Localities of examined specimens of A. inexpectatus (red triangle) and A. vandykei (black dots).

Fig. 40. Seasonalities of adult Asydates species, by month, based on collection records in the Material Examined sections.

Fig. 47. Pristoscelis vandykei (= Asydates vandykei), holotype male, dorsal, left lateral, frontal, and pronotal views and labels. Deposited in CAS. Photographs by Rachel Diaz-Bastin, California Academy of Sciences.

Fig. 19. Asydates species, ventral view of male abdomen showing dense, white setae concentrated medially on ventrite 1. A) A. kumeyaay, B) A. ruficauda.

Fig. 26. Asydates species, median lobe of aedeagus, right lateral view. A. ruficauda: A) CA: Riverside Co.: Lake Elsinore, B) CA: Riverside Co.: Sycamore Canyon Park, C) CA: Inyo Co.: Westgard Pass Road, D) UT: Washington Co.: Lytle Preserve. E) A. washoe, NV: Lyon Co.: 7.2 km south of Sweetwater Summit on Highway 338, F) A. inexpectatus, CA: San Bernardino Co.: 1.6 km north of Hodge. Scale bars = 0.5 mm.