Synemon anthracica Kallies & Edwards, 2020

Kallies, Axel, Edwards, Edward D. & Williams, Andrew A. E., 2020, New and little-known sun-moth species from Australia (Lepidoptera, Castniidae), Zootaxa 4895 (2), pp. 151-195 : 169-173

Synemon anthracica Kallies & Edwards sp. n.

Darkling Sun-moth

Figs 43–49

Literature: Nielsen 1999: 171, fig. 3 (misidentified as Synemon gratiosa Westwood 1877 ); Williams et al. 2016: 102–104, figs 12, 13 (as ‘ Synemon sp. Bob Hay’).

Material examined. Holotype: Ƌ ‘ 32.46S 119.03E Dragon Rocks 33 km N of Newdegate, W.A. 18 Feb. 1997 E.S. Nielsen’ ( Figs 43, 44 ) ( ANIC) . Paratypes: 1Ƌ, E of Hyden , 8.ii.1985, R.W. Hay ( Fig. 47 b–d, genitalia slide 11839) ( ANIC) ; 1Ƌ, E of Hyden , 15.ii.1985, R.W. Hay ( Fig. 47a , genitalia slide 11840) ( ANIC) ; 1Ƌ, E Hyden , 8.ii.1985, S. L. ( MVM) ; 22Ƌ, 3♀, Tarin Rock, 26 km W Lake Grace , 33.07S 118.10E, 17.ii.1997, E.S. Nielsen ( Figs 45, 46 , 48 ) genitalia slide 11919 ( ANIC) ; 14Ƌ, 3♀, Dragon Rocks, 33 km N Newdegate , 32.46S 119.03E, 18/ 19.ii.1997, E.S. Nielsen (genitalia slide 11921 ( ANIC) ; 4Ƌ, 2♀, Dragon Rocks Nat. Res., 33 km N Newdegate , 17–19.ii.1996, T.F. Houston & C.K. Boase ( WAM) ; 2Ƌ, 1♀, Dongolocking Nat. Res., 28 km NNW Dumbleyung , 20–21.ii.1996, T.F. Houston & C.K. Boase ( WAM) ; 1♀, Amery Nat. Res. , 3108.881’S, 11705.688’E, 20.ii.2010, A.A.E. Williams ( WAM) ; 6Ƌ, Corrigin Bushland , 5 km SW Corrigin , 3220’21.8”S, 11749’52.1”E, 15.ii.2010, A.A.E. Williams ( WAM) ; 1♀, Amery Nat. Res. , 3109’05.0”S, 11705’21.0”E, 27.ii.2016, A.A.E. Williams ( WAM) ; 3Ƌ, Elphin Nat. Res. , 3051.728’S, 11641.531’E, 1.iii.2010, A.A.E. Williams ( WAM) ; 1Ƌ, 1♀, Great Northern HWY, 100 km N Northhampton , 2728’15.2” S 11442 ’24.3”E, 24.iii.2011, A.A.E. Williams ( WAM) ; 8Ƌ, 3♀, Gu-nyidi - Wubin Rd , Nat. Res. at Gunyidi, 3008’46.5”S, 11604’39.7”E, 1.iii.2010, A.A.E. Williams ( WAM) ; 3Ƌ, Gunyidi Nat. Res. , 3011’27.8”S, 11602’05.1”E, 19.ii.2016, A.A.E. Williams ( WAM) ; 9Ƌ, 2♀, Heathland Nat. Res. , 3306.224’S, 11840.348’E, 16.ii.2010, A.A.E. Williams ( WAM) ; 1Ƌ, Hopkins Nat. Res. , 3243.187’S 11817.273’E, 15.ii.2010, A.A.E. Williams ( WAM) ; 2Ƌ, 1♀, Hyden - Norseman Rd , 115 km E Hyden , 3219’07.2”S, 12004’57.0”E, 11.ii.2016, A.A.E. Williams ( WAM) ; 2Ƌ, Hyden - Norseman Rd , 6 km SW McDermid Rock , 3203’54.5”S, 12041’31.3”E, 12.ii.2016, A.A.E. Williams ( WAM) ; 1♀, Hyden - Norseman Rd , 147 km E Hyden , 3214’19.0”S, 12024’28.8”E, 11.ii.2016, A.A.E. Williams ( WAM) ; 1Ƌ, 2♀, Hyden - Norseman Rd , 52 km E Hyden , 3225’20.0S, 11924’59.0”E, 11.ii.2016, A.A.E. Williams ( WAM) ; 3Ƌ, Kalbarri N.P., 2748’24.4” S 11428 ’03.7”E, 24.iii.2011, M.R. Williams ( WAM) ; 1Ƌ, 1♀, Kulin - Holt Rock Rd , 3241’21.6”S, 11904’01.7”E, 15.ii.2011, A.A.E. Williams ( WAM) ; 3Ƌ, North Tarin Rock Nat. Res. , 3300.197’S, 11813.664’E, 15.ii.2010, A.A.E. Williams ( WAM) ; 8Ƌ, Tarin Rock Nat. Res. , 3307.192’S 11810.177’E, 16.ii.2010, A.A.E. Williams ( WAM) ; 3Ƌ, 2♀, Pallarup Nat. Res. , 3315’22.5” S 11944 ’45.9”E, 15.ii.2011, A.A.E. Williams ( WAM) ; 1♀, Quairading Bushland, 2.5 km WSW Quai-rading, 3201’14.0”S, 11722’14.0”E, 23.ii.2011, A.A.E. Williams ( WAM) ; 1Ƌ, Quairading Nat. Res. , 3201’22.9” S 11721 ’59.6”E, 14.ii.2015, M. Peterson ( WAM) ; 4Ƌ, 25 km SE Quairading , 3208.626’S 11736.877’E, 15.ii.2010, A.A.E. Williams ( WAM) ; 5Ƌ, 3♀, Quairading Nat. Res., 3201’22.9” S 11721 ’59.6”E (5Ƌ, 1♀), 3201’26.6” S 11721 ’54.5”E (1♀), 3201’22.9” S 11721 ’54.5”E (1♀), 19.ii.2015, A.A.E. Williams ( WAM) ; 12Ƌ, 3♀, Wyalkatchem Nat. Res. , 3110.237’S 11724.264’E, 20.ii.2010, A.A.E. Williams ( WAM, CAK) ; 13Ƌ, 2♀, Wyalkatchem Nat. Res. , 3110’13.4” S 11724 ’18.5”E, 15.ii.2013 (9Ƌ, 1♀), 25.ii.2013 (4Ƌ, 1♀), A.A.E. Williams ( WAM, ANIC) ; 2Ƌ, 1 km SE Caenyie Rock, 3057’36.9” S 12044 ’41.9”E; 1Ƌ, 1♀, Brand Highway , Yathroo, WA 30.79328°S 115.58327°E, 29.ii.2020, R. Eastwood ( WAM) ; 1♀, Dedari , i.1958, A.M. Douglas, R.P. McMillan ( WAM) ; 1Ƌ, 5 km W of Dedari , 3110’28” S 12011 ’56”E, 2.ii.1997, P. Hutchinson ( CPH) .

Etymology. The species’ name is derived from the Greek anthrakítçs and relates to the dark colour of the moths.

Description. Male ( Figs 43, 44 ). Alar expanse 36–41 mm, forewing length 17–19 mm, body length 18–19 mm. Head, vertex with grey piliform and lamellar scales, frons with grey piliform scales, lower half pale grey, labial palpi directed forwards, not reaching frons, white, haustellum vestigial, antenna black annulated with white scales, each antennal annulus with several fine setae directed posteriorly, distal few flagellar annuli white beneath, club expanding gradually, black above, white basally beneath, nudum 16–18 black, on anterior half of club, apiculus long narrow. Thorax above grey, of mixed piliform and broad lamellar scales, beneath straw-coloured to pale grey, legs yellow brown above, white beneath, epiphysis clothed in short spines, pointed at tip, reaching to slightly beyond end of foretibia. Abdomen grey above, T2, T3 with numerous long grey scales, beneath pale grey.

Forewing costa slightly arched, apex rounded, termen rounded, inner margin almost straight. Upperside grey with markings of white, blue grey, and black scales; basal third of wing dark grey, almost obscured by blue grey scales, with a grey spot at end of cell, beyond and below end of cell, a line of small short black streaks from M1 to CuP, those along M veins longer end narrower, median area of wing grey heavily suffused with blue grey, a subapical band of white spots from R2 to M1, disjunct at R5, largest spots near costa, beyond these scattered grey scales, a subterminal row, from costa to dorsum, of black spots surrounded by blue grey scales, submarginal area of wing dark grey suffused with blue grey except narrowly along veins, a narrow terminal black line. Cilia dark grey. Underside black with straw-coloured and white markings; a straw-coloured costal mark from base to half of costa, a straw-coloured spot at end of cell sometimes with another similar spot near costa, a narrow subapical band from R2 to M3, white outlined with straw-coloured scales, the submarginal band reduced to indistinct spots on the anterior half of wing, one at apex white, others pale grey and becoming very indistinct, and a terminal area black. Cilia dark grey.

Hindwing termen evenly rounded, tornus rounded. Upperside entirely black, basal third with pale yellow grey sheen. Cilia black with white patch near apex. Underside black with white spots; grey along costa and broadly at tornus, a small white spot at distal end of cell, a median band of small white spots from M1 to 1A+2A, a large gap between M2 and CuA1, all three spots small and well separated, a submarginal row of white spots between veins from Rs to 1A+2A gradually increasing in size towards tornus, a terminal area black, anal area grey merging into a tornal area of pale grey, without a tornal spot. Cilia grey, paler at apex.

Female ( Figs 45, 46 ).Alar expanse 42–47 mm. Similar to male, larger, wings longer; coloration similar to male. Sometimes the upperside hindwing has a trace of two spots of the median band, present as paler patches in the black ground colour.

Male genitalia ( Fig. 47 ). Uncus broad short pointed at tip with long setae; gnathos arms shorter than uncus; anal tube lightly sclerotized; tegumen broad, slightly curved in lateral view, narrowing anteriorly; vinculum evenly sclerotized; saccus with well-marked bifurcated arms; juxta, sclerotized, curved anteriorly; valva elongate, strongly curved ventrally, tip truncated into upturned point, sacculus and costa with stout setae; phallus long, well sclerotized, of even diameter, tip oblique, straight then curved anteriorly with phallobase not recurved, attached to a ventral sclerotized strip; ductus ejaculatorius about as long as phallus, with several coils.

Female genitalia ( Fig. 48 ). Papillae anales short, pointed, sclerotized; ovipositor long, extensible, sclerotized, with numerous stout dorsal and lateral spines towards tip; apophyses long, heavily sclerotized, apophyses anteriores about half the length of apophyses posteriores which extend from the tip of the papillae; sinus vaginalis with two short lateral sacs; ostium bursae from unsclerotized window almost a half in from posterior margin of S7; ductus seminalis from near ostium; ductus bursae not coiled; corpus bursae large, approximately spherical, without signum.

Diagnosis. This species is a member of the S. sophia group but is unique among the congeners in having almost completely black hindwings. It is clearly related to S. nupta but differs in its smaller size, the less conspicuous pattern of the forewing, the entirely black hindwing (without a trace of scarlet) and the lack of any trace of scarlet on the underside of both wings. Unlike S. nupta the haustellum is vestigial; it is the only member of the S. sophia group to lack a functional haustellum. It resembles S. nupta in the general pattern of the pale grey or blue-grey markings on the forewing, the pattern and small size of the spots on the underside, the lack of a conspicuous tornal spot on the hindwing, in the shape of the wings and the gradual enlargement of the flagellum into the club of the antenna.

Variation. Within populations, S. anthracica sp. n. varies greatly in size. In some females two spots of the median band of the forewing above appear as ‘ghosts’, just visible in good specimens.

Distribution. This species has been recorded from 100 km north of Northampton and Kalbarri National Park in the north, southwards to Gunyidi, and Yathroo in the northern sandplains, through the Wheatbelt to Tarin Rock Nature Reserve and Pallarup Nature Reserve, and inland to Caenyie Rock near Coolgardie and near McDermid Rock on the Hyden–Norseman Road.

Habitat and Biology. The flight period runs from mid-February to the end of March. Populations in southern localities emerge earlier than those in the north (Williams et al. 2016). The small semaphore sedge Mesomelaena preissii Nees (Cyperaceae) is the larval food plant (Williams et al. 2016). The sun-moth’s behaviour in and around Tussocky Cord-rush Ecdeiocolea monostachya F. Muell. (Ecdeiocoleaceae) suggests that this may also a larval food plant. This sun-moth is found in heath, shrubland and sedgeland, often in association with Tamma ( Allocasuarina campestris (Diels) L.A.S.Johnson , Casuarinaceae ). In the more northerly parts of its range this species is frequently found where E. monostachya and small semaphore sedges ( Mesomelaena species) occur together. Males fly over areas of open low heath or sedgeland in search of un-mated females (Williams et al. 2016).

Remarks. This species was referred to as Synemon sp. ‘Bob Hay’, the Darkling sun-moth, by Williams et al. (2016).

Figures

FIGURES 43–46. Synemon anthracica sp. n., upperside (left), underside (right). 43, 44. Ƌ, holotype, Dragon Rocks (ANIC). 45, 46. ♀, paratype, Tarin Rock (ANIC).

FIGURES 47, 48. Synemon anthracica sp. n. 47. Male genitalia, paratypes. a. Unrolled. b. Lateral view, right valva removed. c. Valva. d. Phallus (genitalia slides 11839, 11840) (ANIC). 48. Female genitalia, paratype. a. Distal part. b. Anterior part. c. Segment 8, ostium, ductus bursae and corpus bursae (genitalia slides 11919) (ANIC).

FIGURES 49–56. Synemon species adults. Upperside (left), underside (right). 49–52. Synemon semaphora sp. n., Ƌ, paratype, Jarrahdale (49, 50) (WAM); ♀, paratype, Metro Road, off Brookton Highway (51, 52) (WAM). 53–56. Synemon petrophila sp. n., Ƌ, Nyabing (53, 54) (ANIC); ♀, paratype, Tarin Rock (55, 56) (ANIC).