Microasydates sanclemente 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 : 555-556

2. Microasydates sanclemente Gimmel and Mayor , new species zoobank.org/ urn:lsid:zoobank.org:act:9E9C648F-5DD3-4595-80FE-D491BDC45597 ( Figs. 6 , 14 , 19, 20 , 26 , 30 , 39 , 44, 45 , 62 , 64 )

Type Specimen. Holotype ♂, deposited in SBMNH, labeled “CA: Los Angeles Co. \ 32.8734°N, 118.4480°W \ San Clemente Isl. , upper \ Cave Cyn., vi.15.2008 \ Caterino&Chatzimanolis [white printed label] // CA BEETLE PROJ \CBP0079731 [blue printed label]// HOLOTYPE ♂ \ Microasydates \ sanclemente \ Gimmel & Mayor 2022 [red printed label]”.

Diagnosis. The body with at least mouthparts, legs, and elytral apices ( Fig. 26 ) pale yellow-orange, and with both pale and dark setae ( Figs. 6 , 14 ); pronotum with a short, tight lateral fringe of pale setae ( Figs. 19–20 ); female pygidium moderately deeply emarginate (as in Fig. 35 ), with a broad median glabrous area ( Fig. 39 ); median lobe of aedeagus with only two ventral teeth and a subapical bulge in addition to the apical hook ( Fig. 44 ); and a distribution on San Clemente Island, California distinguish M. sanclemente from all other species of Microasydates .

Description. Body ( Figs. 6 , 14 ) small, somewhat stout; shiny with slight bronze luster; male pronotum and elytra with distinct but weak isodiametric microsculpture, weaker still on head; female pronotum with microsculpture variable, similar to male or stronger, distinct, somewhat more weakly indicated on elytra. Length 1.80–2.14 mm (male mean: 1.88 mm; female mean: 2.05 mm); width 0.80–0.94 mm (male mean: 0.81 mm; female mean: 0.89 mm). Body ( Figs. 6 , 14 ) entirely black except the following: antennae and legs dark reddish-brown, antennae apically becoming darker, tibiae and tarsi often lighter reddish-brown; elytral apices ( Fig. 26 ) bright reddish brown in a well-defined lunule across the suture and extending along lateral margins anywhere from one-fifth to one-third elytral length; apex of abdomen around genital opening and sometimes female with apical 2–3 ventrites bright reddish brown. Pubescence moderately dense, completely reclining, mostly rusty-brown to black, but patches of pale silvery setae present over most of head dorsally (occiput with patch of rusty setae), pronotum (large central patch consisting of rusty setae), scutellar shield, and elytra at extreme basal margin and in a broad sub-basal band extending across and along suture to scutellar shield, in certain light giving the elytra a tricolored (black-cream-red) appearance, ventral surface with scattered pale setae; pronotal fringe short and comprised of pale setae, not projecting but somewhat loose; elytral fringe longer, mostly pale except at apex, somewhat loose. Punctation shallow and inconspicuous on head and pronotum, coarser on elytra, punctures separated by about one puncture diameter or less near elytral base but becoming sparser apically. Head: Not conspicuously enlarged, very slightly wider in male, distinctly narrower than pronotum, eyes rounded laterally, bulging; 1.54–1.69 times wider than interocular distance (male mean: 1.64; female mean: 1.56). 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. 19, 20 ) wider than long, appearing transverse, 0.69–0.75 times as long as wide (male mean: 0.71; female mean: 0.72); widest at middle; lateral edges straight and diverging to middle in basal half, then straight and converging to anterior margin, not constricted, lateral bead very weakly crenulate; anterior and posterior angles obsolete, broadly rounded. Elytra moderately elongate, broadly oval, more elongate in female, elytron 3.26–3.61 times longer than wide (male mean: 3.38; female mean: 3.48), elytra at humeri slightly wider than pronotum; elytral epipleuron distinct at base, tapering gradually and becoming obsolete near apex of abdominal ventrite 3 in both sexes, lateral carina barely visible in dorsal view for entire length, not explanate; apical margin broadly rounded, sutural angle absent in male ( Fig. 26 ), sometimes weakly present in female, margin very weakly serrulate in both sexes.All tibiae with fine, pale setae along external margin; pro- and mesotibiae with very inconspicuous, short, slender and sparse spines arranged along external margin, spines slightly more conspicuous in female; metatibia of male with weak brush of dense, fine, black setae in apical one-third on inner margin, brush virtually absent in female. Abdomen: Male ventrites 4 and 5 weakly flattened or depressed medially, with transverse field of black spiculate setae (very inconspicuous on the dark abdomen) in apical half medially on ventrite 4, a few black spiculate setae present apicomedially on ventrite 3, black spiculate setae absent from ventrite 5. Pygidium of male with scattered sparse setae, glabrous in ill-defined basal triangle, with apex of pygidium truncate ( Fig. 30 ); female pygidium sparsely setose with wide median glabrous strip ( Fig. 39 ), apex with small, weak, arcuate emargination. Spiculum gastrale with basal strut short, distinctly less than one-half diameter of ring. Median lobe of aedeagus in lateral view ( Fig. 44 ) with apical limb distinctly longer than basal limb, apex short, stout, strongly acute and sharply directed ventrally, ventral margin of apical limb with pair of ventrolateral teeth at same level (near proximal end of apical orifice), with slight ventral bulge between paired teeth and apex; tegmen ( Fig. 45 ) relatively elongate, with slight constriction near base of ring. Female internal terminalia not studied.

Etymology. Named after San Clemente Island of the California Channel Islands, the type locality. The name is to be treated as a noun in apposition.

Host Plant Associations. No host plant records are available for this species.

Seasonal Distribution. 8 May to 15 June ( Fig. 64 ).

Geographic Distribution. Known only from San Clemente Island, southernmost of the Channel Islands off the coast of southern California .

Paratypes (6). CALIFORNIA: Los Angeles County: San Clemente Island, above Twin Dams Canyon, 32°54′13.03′′N, 118°28′28.08′′W, loamy grassland, 8 May 2010, US Navy (1♀, SBMNH); San Clemente Island , upper Cave Canyon , 32.873 4, −118.4480, 15 June 2008, Caterino and Chatzimanolis (1♂♂, 4♀♀, SBMNH) .

Remarks. Microasydates sanclemente shares many characters with M. punctipennis of Santa Catalina Island, including the shape of the aedeagal median lobe, but may be readily separated from that species by the presence of pale setae on the pronotum and elytra (pale setae absent in M. punctipennis ), the conspicuously pale reddish elytral apices (elytra uniformly dark in M. punctipennis ), and the more transverse pronotum.

Figures

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. 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. 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. 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. 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.