Synemon arkaroola Kallies & Edwards 2018, spec. nov.
Creators: name: Kallies, Axel
name: Edwards, Ted
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Castniidae
Synemon
Synemon arkaroola

description: Synemon arkaroola spec. nov.
Figs 1–4, 17, 19
Type material: Holotype. ♂ (Figs 1, 2), South Australia, 30°17’S 139°22’E, 4.2 km NNE Arkaroola village, 25 Oct 1993, E. D. Edwards & E. S. Nielsen (in ANIC, database No. 31-014584). Paratypes. South Australia, Flinders Ranges: 16 ♂, same data as holotype (male gen. 11795, 11831); 14 ♂, 2 ♀, 30°11’S 139°17’E, Petalinka Falls, Arkaroola Stn, 20 Oct 1993, E. D. Edwards & E. S. Nielsen (wing slide 16601, female gen. 11910); 5 ♂, same data but 21 Oct 1993; 7 ♂, 3 ♀, same data but 22 Oct 1993 (female gen. 11909); 12 ♂, 2 ♀, same data but 23 Oct 1993 (male gen. 18538); 14 ♂, 1 ♀, 30°17’S 139°21’E, 3 km NNE Arkaroola village, 24 Oct 1993, E. D. Edwards & E. S. Nielsen; 4 ♂, 1 ♀, 30°31’S 139°18’E, Balcanoona Ck, Gammon Ra. NP, 26 Oct 1993, E. D. Edwards & E. S. Nielsen (male gen. 11794); 8 ♂, 31°40’S 138°36’E, Ulowdna Ck nr HS South Flinders Ra., 6 Nov 1997, E. D. Edwards (all in ANIC, database Nos range from ANIC 31-014545 to ANIC 31-014633); 1 ♂, Yutnamutana Gorge, Arkaroola Stn, 23 Oct 1969, G. F. Gross (SAMA); 1 ♀, 31°28.4’S 138°38.6’E, off Rd to Oraparinna, 11 Dec 2004, A. Kallies & D. J. Hilton (CAK).
Description. Male (Figs 1, 2). Forewing length 13–18 mm (average 15.95 mm, n = 10). Head with vertex grey; thick piliform grey scales obscuring black lamellar scales; frons with dense dark grey piliform scales and dense white lamellar scales beside eyes; labial palpi short, porrect, appressed to head, reaching frons, white; haustellum present, coiled; antenna dark grey, narrowly annulated with white, club grey and pale grey above, white and grey beneath, black in anterior third, expanding fairly abruptly, nudum consisting of 9 antennomeres, apiculus small of a single annulus. Thorax above dark grey of mixed dark grey piliform and black lamellar scales, beneath pale grey; legs grey above, yellow grey beneath, epiphysis clothed in minute spinules, inserted just below about half length of fore tibia, short, strong, spine-like, not reaching end of fore tibia, tibial spurs 0-2-4. Abdomen with basal segments dark grey above, remainder brown, T2–T3 with numerous long grey scales, ventrally pale grey with white scales at distal ends of segments.
Forewing with costa gently arched, apex rounded, termen rounded, inner margin almost straight. Dorsal side dark grey with markings of white or ash grey; whole wing heavily dusted with ash grey scales; a white patch at end of cell; veins in median area from R4 to CuP black; an ill-defined white post median band extending from R4 to CuA2, crossed by black and grey veins, beyond this a band of dark grey and a subterminal area with a heavy dusting of ash grey scales; termen grey; cilia dark grey.
Hindwing with termen evenly rounded. Dorsal side dark grey to black, rich orange dot at end of cell, outer half of wing rich orange extending from tip of Rs to tornus; a narrow terminal line dark grey; tornus orange; anal area dark grey at base, orange distally; cilia dark grey.
Forewing ventral side with costa yellow, pale grey towards apex; basal third of wing black, outer two thirds orange; orange patch at end of cell joined to outer two thirds of wing but separating a large black patch beyond end of cell from basal black area; basal black area sharply angled at base of CuA1; narrow terminal line grey; cilia grey.
Hindwing ventral side with costa black with orange scales towards base, basal half black; orange spot at end of cell; a broad post median band of orange spots extending from Rs to tornus, separated from subterminal row by a narrow dark grey line; a subterminal row of orange spots extending from Rs to tornus, separated by black veins and running into the post median band below 1A+2A; tornus orange; anal area orange, grey at base; cilia orange grey.
Female (Figs 3, 4). Forewing length 16–19 mm (average 17.9 mm, n = 9). Similar to male, larger, forewing narrower, hindwing with orange streak along costa, orange cell spot larger and extending inwards to base, orange markings more extensive. Forewing ventral side more orange towards base. Hindwing ventral side with costa orange with scattered black scales, orange markings much more extensive than in male, outer half of wing orange with a subterminal row of ill-defined black spots between veins from Sc+R1 to 1A+2A, a narrow black terminal line.
Male genitalia (Fig. 17). Uncus short, of uniform width with small lateral bumps that are covered with short setae; gnathos arms sclerotised; tegumen broad; saccus with short arms; valva with a short and upturned spine at tip, with numerous short setae; phallus well sclerotised, broadening anteriorly, strongly and evenly curved, apically pointed, anteriorly with phallobase slightly recurved; ductus ejaculatorius longer than phallus.
Female genitalia (Fig. 19). Papillae anales short, pointed sclerotized, with multiple setae; ovipositor long, narrow, extensible, sclerotised, with stout lateral setae towards tip, without any setae at the base; apophyses long, well sclerotised, apophyses anteriores about half length of apophyses posteriores; ostium bursae at posterior edge of S7; ductus bursae long, narrow, straight; corpus bursae large, elongate spherical, without signum.
Variation. In males, the orange spot in the cell of the hindwing varies in shape from almost round to a short, broad streak; it is usually separated from the outer orange band but occasionally they run into each other. The colour of the outer band of the hind wing can vary from brownish orange to orange to yellowish orange. The forewings are constant in pattern but sometimes the pattern is more or less emphasised. The females show a similar range of variation as the males.
Diagnosis. Synemon arkaroola spec. nov. belongs to a group of grass feeding Synemon species that are distributed over the arid zone of the Australian continent. It is easily recognizable by its size and brightly orange marked hindwings. It is similar to S. brontias (Figs 5–8, 18, 20–23), which was described from Carnarvon in Western Australia (Meyrick 1891) but also occurs in the north of Queensland. However, S. brontias is smaller (forewing length of males 13–16 mm, average 14.3 mm, n = 10; females 15–17.5 mm, average 16.1 mm, n = 3; measurements based on material from Queensland), the coloration of the hindwings in the males is pale orange, crossed by distinctly marked veins (deep orange in S. arkaroola, without marked veins). Furthermore, in S. brontias the distal half of the forewing is much lighter, in particular in males. Males of S. brontias lack the orange spot in the black basal half of the hindwing while it is very small in females (present in S. arkaroola, large in females). In both sexes of S. brontias, the black marking on the ventral side of the hindwing are more extensive. Finally, females of S. brontias have a distinct row of black subterminal spots on the ventral side of their hindwing, which is lacking or indistinct in S. arkaroola. The two species, S. brontias and S. arkaroola also differ in their genitalia. In male S. brontias (Figs 18, 22), the uncus is narrower and pointed; the saccus arms are vestigial; the spine at the tip of the valva has a broader base; the phallus is broader and more arched. In female S. brontias (Figs 20, 23), the apophyses anteriores are relatively long, reaching the anterior edge of the corpus bursae.
Other related species, including S. nais (Figs 9–12) and S. theresa (Figs 13, 14), both of which occur in South Australia and S. austera (Figs 15, 16), which occurs near Carnarvon in Western Australia (Meyrick 1891, Williams et al. 2016), can be readily distinguished by their different wing markings. None of these related species occurs in the same habitat as S. arkaroola.
Distribution. S. arkaroola spec. nov. is only known from the Flinders Ranges in South Australia.
Habitat and Biology. S. arkaroola spec. nov. was found along dry creek beds where their foodplant, Scented Lemon Grass Cymbopogon ambiguus, commonly grows. They were also seen on the adjacent arid rocky slopes. Specimens were also found high on a hill side where a porous layer of rock maintained an invisible seepage of moisture. Here, the foodplant was growing thickly in a narrow band coinciding with the rock stratum. Most adult specimens were collected between the 20th of October and the 7th of November; however, a single specimen was collected on the 11th of December, suggesting a more extended flight period at least in some years. The larvae were found in galleries among the roots of the host plant. Based on the fact that small and what appeared to be fully grown larvae were observed together in early December, it is likely that larval development takes at least 2 years.
Derivatio nominis. The species name acknowledges the Arkaroola Resort in the northern Flinders Ranges where the moths are found. Run by the Sprigg family, the Resort has made accessible the stark grandeur of the Ranges to many people who would otherwise be unable to see this wonderful region. The name originally derives from Arkaroo, a mythical monster of a dreamtime or creation story by the area’s first people, the Adnyamathanha.
Additional material examined. Synemon brontias: 1 ♂, syntype ‘ Carnarvon W. Australia 26/10/86 ’, ‘ Meyrick coll. B.M. 1938-290’, ‘ Specimen photographed for CHECKLIST AUST. LEP Film 60/3’ (BMNH, Fig. 21); 17 ♂, 1 ♀, Queensland, 20°43’19’’S, 145°10’44’’E, White Mountains NP, 570 m, 7 Sep 2004, M. F. Braby & L. Aitchison (ANIC, Figs 5-8); 6 ♂, 3 ♀, Queensland, 20°42’S, 145°10’’E, 2.2 km N of Microwave Stn, Burra Ra, 4 Sep 1994, M. F. Braby (male gen. 11863, 11864, female gen. 13068) (ANIC). Synemon austera: 1 ♂, Western Australia, 24°49’S, 113°43’E, 9km NE of Carnarvon, 20 Oct 1992, E. D. Edwards & E. S. Nielsen (ANIC, Figs 15, 16). Synemon theresa: 1 ♂, South Australia, Stoneyfell, 26. Dec 1938, F. M. Angel (ANIC, Figs 13, 14). Synemon nais: 1 ♂, Victoria, 3 km ENE of Walpeup, 27 Oct 1993, E. D. Edwards & E. S. Nielsen (Figs 9, 10, ANIC); 1 ♀, South Australia, 9 mi SE by S of Nundroo HS, 21 Oct 1968, Britton, Upton & Balderson (ANIC, Figs 11, 12).
Remark. Synemon brontias is currently known only from two disjunct regions. The four syntypes and a few additional specimens were collected near Carnarvon, Western Australia (Meyrick 1891, Williams et al. 2016). Another population was discovered in northern Queensland by Michael Braby later. Although specimens from both populations are very similar, there are small differences such as the saccus arms (better developed in the genitalia of the type specimens examined) and the spine at the tip of the valva (less pronounced base in the genitalia of the type specimens examined, compare Figs 18 and 22). However, important characters are destroyed or not visible in the genitalia preparations of the syntypes (Figs 21–23). Therefore, more material is needed to determine whether both populations indeed belong to the same species.
description: Published as part of Kallies, Axel & Edwards, Ted, 2018, A new sun moth species from the Flinders Ranges in South Australia (Lepidoptera, Castniidae), pp. 292-300 in Zootaxa 4369 (2) on pages 293-299, DOI: 10.11646/zootaxa.4369.2.9, http://zenodo.org/record/1135760