Gallaba kirkpatricki McQuillan & Chen, 2024

MCQUILLAN, PETER B., CHEN, JINGYI & FOUNTAIN-JONES, NICHOLAS M., 2024, Two remarkable new species of the Australian moth genus Gallaba Walker (Lepidoptera: Notodontidae, Notodontinae) from the highlands of Tasmania, Zootaxa 5543 (3), pp. 368-382 : 375-380

Gallaba kirkpatricki McQuillan & Chen sp. nov.

urn:lsid:zoobank.org:act:D6F68EF9-4DA7-4EF6-9F40-CBE254E2DB4C

( Figures 4, 6–13, 15 )

Informal designations: Gallaba ANIC2; BIN AAO9878 (BOLD)

Holotype: ♂ labelled “ 42°42´S 146°35´E Tasmania, Lake Dobson 980m 25 NOV. 1988 P.B. McQuillan, E.S. Nielsen (10 ANIC-00255 ANIC). [ Lake Dobson road 42.700°S 146.583°E]” ( ANIC).

Paratypes:

1♂, “ 41°50´S 146°05´E Tasmania, Pelion Hut 870m 10 JAN. 1991 E.S. Nielsen, E.D. Edwards [41.829°S 146.046°E 860m] 10 ANIC-00253 ” ( ANIC).

1♂, “ 41°50´S 146°03´E Tasmania, Pelion Hut 870m 18 NOV. 1991 E.S. Nielsen, M. Horak 10 ANIC-00254 ” ( ANIC) .

1♀ “ 41.8338°S 145.5266°E TAS., Mount Read 925m 4 DEC. 1990 P.B. McQuillan Athrotaxis-Nothofagus mixed forest uvl NRCP | Databased 122345 PBMcQ” ( PBMcQC) .

2♂, 41.8418°S 145.5248°S TAS., Mount Read 975m 7 JAN. 2017 PB McQuillan & S Fayed rainforest Athrotaxis selaginoides + Nothofagus cunninghamii | Databased 112109, 112110 PBMcQ” (PBMcQC, QVM).

13♂, “ 42.68111°S 146.59104°E TAS., Pandani Grove , Mount Field NP 1050m 3 JAN. 2012 PB McQuillan montane rainforest uvl | Databased 122329-122341 PBMcQ” ( AM, NMV, PBMcQC, SAMA, TMAG) .

1♂, “ 42°42´S 146°35´E Tasmania, Lake Dobson 980m 25 NOV. 1988 P.B. McQuillan, E.S. Nielsen [ Lake Dobson road 42.700°S 146.583°E] 10 ANIC-00255 ” ( ANIC) .

4♂, 1♀ “ 43.19812°S 146.7709°E TAS., Hartz Mountains 750m 11 JAN. 2019 P.B. McQuillan, J. Chen & S. Henry mvl subalpine wet forest | Databased 122342, 122343, 122344 PBMcQ” ( AM, NMV, PBMcQC, SAMA, TMAG) .

6♂, 43.21733°S 146.77129°E TAS., Hartz Mtns Nat Pk 855m 19 DEC. 2015 PB McQuillan & A. Throssell montane rainforest | Databased 116884-116889 PBMcQ ” ( PBMcQC) .

Diagnosis. Both the males and females of this species are very distinctive within the genus in having the broadest wing shape and uniformly reddish brown coloration without any obvious pattern.

Etymology: We name this species in recognition of Distinguished Professor Jamie Kirkpatrick of the University of Tasmania for his pioneering research into alpine ecology and indefatigable advocacy for the conservation of the Tasmanian wilderness and its biota.

Description ( Figs 7, 9 ). Wingspan male 42-44mm, female 46-48mm. Stout-bodied for the genus.

Head ( Fig. 8 ): with frons bearing a long anterior tuft; haustellum present. Palpi long, porrect or slightly ascending, hairy; terminal joint long. Antennae pectinated to apex in both sexes. Male antenna with 55 segments, width of flagellum 0.19 mm, maximum length of ramus 4.18 mm, ratio of ramus length to flagellum width is 21:9. Female antenna with 56 segments, width of flagellum 0.16 mm, maximum length of ramus 1.29 mm, ratio of length to width is 8:1.

Thorax: with vestiture long and dense, decumbent and not projecting beyond or above thorax. Forewing broad, with areole rather large, M 1 from near base of areole, M 2 from middle, R 5 and R 2 separate, or rarely R 2 connate. Hindwing with M 1 and Rs short-stalked, Sc+R 1 closely approximated to cell from base to near distal end, M 2 from middle or below middle, M 3 and Cu 1 connate from lower angle of the cell. Posterior tibiae with two pairs of spurs, the inner very long, twice as long as the outer.

Abdomen: with a small dorsal crest on basal segment.

Male genitalia ( Fig. 4 ). Uncus well sclerotised, massive, distally bifid and the arms diverging. Socii large, well sclerotised, distally spatulate. Subscaphium present. Valvae long, relatively narrow in distal half; anterior margin unadorned; sacculus (posterior margin of the valva) not modified, without androconia. Vinculum broadly rounded. Aedeagus stout, distally attenuate and recurved, a transverse ridge present near middle; caecum short. Cornuti present, in the form of a cluster of short thorns.

Female. Differs from male in being slightly larger, with shorter antennal rami and a slightly narrower forewing wing shape.

Female genitalia ( Fig. 6 ). Ovipositor very short. Papillae anales stout, round-pointed, with numerous short and long setae; Apophyses posteriores short, ca x2 length of apophyses anteriores which are short and straight. Corpus bursae very short ca one third length of A7, membranous, flask-shaped.

Genetic Analysis

Relationships: Four public barcode-compliant individuals of this new species are indexed in the BOLD registry, comprising a single Barcode Index Number BIN AAO9878. Average p-distance within this BIN is 0.27% and the maximum p-distance is 0.55%. The nearest neighbour (p-distance 10.09%) is a heterocampine notodontid Harpyia longipennis (Walker, 1855) from SE Asia (voucher NOTPM029-10 and a member of BIN URI: BOLD:AAM4156), an unlikely close relationship.

Life History

Eggs ( Fig. 10 ). The hemispherical eggs are of the upright type; glossy, pearly whitish, (average 2.04 mm wide at base x 1.32 mm high, width range 1.90–2.10 mm, height range 1.18–1.42 mm).

Larva—fourth instar ( Figs 11 , 12, 13 ). The larva exhibits at least three apomorphies typical of notodontid larvae: two MD setae present on segment A1, a membranous stipital lobe and the smooth-edged cutting blade of the mandibles ( Godfrey et al. 1989). The stipital lobe is a projection on the stipes which obscures the dorso-posterior aspect of the galea ( Grimes & Neunzig 1986a,b). However, this larva lacks the more elaborate modifications seen in some other Australian notodontid larvae such as an eversible gland on the underside of the prothorax (present in Psalidostetha Swainson for example), elongated thoracic legs (as in Stauropus Germar ) or modified hind claspers in the form of stematophores (present in Antimima Turner ).

Body dorsally appears pink with irregular narrow creamy white stripes; ventrally white; spiracles black. A narrow reddish pink lateral line just above the spiracles. Setae white but dorsal setae on A8–A10 dark brown. Pinacula small, most arising from discrete patches of white or yellowish epidermis. Secondary setae absent.

Head capsule robust, rounded, wider than thorax, epicranial notch shallow; uniformly orange-brown, without markings or maculation. Stemmata 1–6 subequal in size; stemma 5 ventral in position, near base of antenna.Antenna relatively short, reaching lower margin of clypeus; terminal seta long, curved, slightly longer than antenna itself; medial segment about as long as wide. Labrum strongly notched. Anteclypeus trapezoidal, slightly protuberant in lateral view. Stipital lobe present. Mandibles symmetrical, stout and heavily sclerotised, with cutting edge smooth and lacking serrations.

Cervical gland apparently absent. Prothoracic shield weakly and unevenly sclerotized, protuberances absent. Pretarsus of thoracic legs with two terminal, spatulate tarsal setae.

Abdominal segments without protuberances; pinacula small and pale brown in colour. Anal shield narrow, pointed, somewhat convex, moderately sclerotised, more so medially.

Prolegs equally well developed on A3–A6, with 11–13 lateral setae on each one. Crochets in an interrupted transverse band as a homoideous uniordinal mesoseries. Paraprocts elongate, shorter than epiproct.

Pupa. Body cylindrical. Integument dark reddish brown, glabrous. Prothorax and mesothorax with integument wrinkled and without tubercules. Metathorax and abdominal segments with integument relatively smooth. Anterior margin of segments A5–A7 with shallow punctures dorsally. Segments A8-10 tapering posteriorly; cremaster narrowly conical.

Female pupa 31 mm long (n = 1), male pupa 31 mm long (n = 1).

Foodplant ( Figs 12, 13 ). Richea pandanifolia Hook.f. ( Ericaceae : Epacridoideae: tribe Richeeae ) an erect pandaniform shrub up to 5m high, endemic to the montane forests and alpine heaths of central, southern and western Tasmania. The long (often> 1m), tapering, strap-like leathery leaves are persistent and sheath the stem after dying. Older plants often show signs of feeding damage ( Fig. 13 ) but plants less than 1.5m tall rarely do so. This plant is locally known as “pandani” after its superficial appearance. In tall wet forest the foodplant is a member of the understorey but in lower shrubland it is often emergent. Evidence of feeding damage persists on the foodplant for many years, preserved in the dead leaves.

Biology: Females lay eggs in small clusters of 3–7 on the lower leaf surface of the foodplant ( Fig. 10 ) beginning about 2 hours after nightfall.

Prior to winter dormancy, three-quarter grown larvae (16.iv.2019) were found hiding in the imbricate leaf bases of pandani, up to three individuals per plant. Larvae retreat to these protected sites which are associated with extensive patches of moist frass ( Fig. 13 ), suggestive of a latrine, although its local redistribution by rainfall may account for this observation. Larvae venture forth at night and feed on the tough, serrated leaf margin. Ragged edge damage is persistent on the long-lived leaves and many large plants show evidence of previous feeding activity.

Disturbed larvae are sluggish but attempt to retreat deeper into the crown of the plant; larvae can further respond by arching their back and regurgitating fluid from the mouth if handled. Pupae were not found on the plant and their location in the field remains undiscovered. Adults of both sexes are attracted to mercury vapour lights at night, but males strongly predominate in numbers.

Notes: G. kirkpatricki sp. nov. lacks the maculation and erect thoracic scale tufts typical of other Gallaba species, although it largely conforms in other morphological features. This species has a superficial resemblance to the russet-coloured males of a large species of Pterolocera Walker ( Anthelidae ) endemic to western Tasmania and whose larvae feed on the clump-forming button-grass Gymnoschoenus sphaerocephalus (R.Br.) Hook.f. ( Cyperaceae ).

Distribution ( Fig. 15 ): Scattered locations in western and southern Tasmania where it occupies montane wet forest to alpine shrubland from 750–980m above sea level. The climate is cool temperate (Köppen climate type is subpolar oceanic Cfc). Mean annual temperature near the Hartz Mountains site ranges from a minimum 4.0°C to a maximum 11.4°C but extremes here range from -4.4°C to 34.9°C. The mean annual rainfall is 1062 mm with a mean monthly range of 62-120 mm ( Bureau of Meteorology (2019), site number 094191, 43.200 °S 146.768 °E elevation 831 m). At Mount Read, the most westerly location, the mean annual temperature ranges from a minimum 2.7°C to a maximum 8.7°C with extremes -5.3°C to 30.4°C. The mean annual rainfall is 3768 mm with a mean monthly range of 187–429 mm. (BoM site number 097085, 41.84°S 145.54°E elevation 1120 m).

Gene Tree. A COI neighbour-joining tree for Gallaba is presented in Fig. 16 and should be regarded as indicative only. The Tasmanian endemic species G. kirkpatricki sp. nov. and G. constellata sp. nov. branch early and are distinctive from each other.

Conclusions and Conservation. We have shown that the highlands of Tasmania are highly prospective for new species of endemic macromoths.The genus Gallaba is probably the most speciose notodontine genus in Australia and this paper has established a foundation for a future revision of this long-neglected group using modern methods.

Both new species are of high conservation value on account of their limited range, apparent rarity and biogeographic novelty. It is possible they are faunal relicts of the Tertiary rainforests largely eliminated by the extensive drying of the Australian landmass ( Byrne et al. 2011), having survived in the mesic climatic refugia which have persisted since the mid Tertiary in the uplands of Tasmania ( Jordan et al. 2016). The unusual hostplant is a member of the epacrid tribe Richeeae which has an estimated (ML) stem age of 33.4 Ma ± 3.5 and 20.6 Ma ± 2.9 for the crown radiation ( Wagstaff et al. 2010).

The conservation prospects for these endemic insects depends on the future security of their habitat and its management in Tasmania. The known and likely foodplants, Richea spp. , are not regarded as fire tolerant and may be locally eliminated by frequent fire ( Kirkpatrick & Dickinson 1984). Fire regimes are changing quickly in Tasmania as climate change is driving more intense fires over larger areas and the fire season is occupying a larger part of the year ( Fletcher et al. 2018), threatening upland plant communities in particular ( Holz et al. 2015)

Some populations of both new species occur in established conservation areas, but others are less secure. G. constellata sp. nov. occurs in the Central Plateau Conservation Area but the southern population is contained within the multiple-use Snug Tiers Nature Recreation Area. G. kirkpatricki sp. nov. occurs in Mt Field National Park and the Hartz Mountains National Park. Populations near Mount Read in the west are partly contained in the Mount Dundas Regional Reserve and the Lake Johnston Nature Reserve, but the montane forests on the northern slopes of the mountain are at risk of forestry operations due to their inclusion in a Permanent Timber Production Zone Land while the western flanks are designated by the Tasmanian government as Future Potential Production Forest.

Figures

FIGURE 11. Freshly preserved fourth instar larva of Gallaba kirkpatricki sp. nov. Scale line 5 mm.

FIGURE 16. COI neighbour-joining tree (uncorrected p-distances) built using MEGA X from 44 DNA barcodes of Gallaba in BOLD. Tree is rooted on the Australian notodontine Hylaeora sp. nr caustopis as the outgroup. Values at the nodes indicate posterior probabilities. “SW-WA” is an undescribed Gallaba confined to the south-west of Western Australia.

FIGURES 3–6. 3. Male genitalia of Gallaba constellata sp. nov. holotype. Scale line = 1 mm. 4. Male genitalia of Gallaba kirkpatricki sp. nov. paratype.Aedeagus in lateral view. Scale line = 1 mm. 5. Female genitalia of Gallaba constellata sp. nov. paratype. Scale line = 1 mm. 6. Female genitalia of Gallaba kirkpatricki sp. nov. paratype. Scale line = 1 mm.

FIGURES 7–10. 7. Gallaba kirkpatricki sp. nov. holotype ♂. Scale line = 10 mm. 8. Gallaba kirkpatricki sp. nov. paratype ♂ showing profile of head. 9. Gallaba kirkpatricki sp. nov. paratype ♀. Scale line = 10 mm. 10. Eggs of Gallaba kirkpatricki sp. nov. on the underside of a Richea pandanifolia leaf in the field.

FIGURES 12–15. 12. Food plant Richea pandanifolia showing leaf damage caused by the larvae of Gallaba kirkpatricki sp. nov.; 13. Exposed leaf base of food plant Richea pandanifolia showing a faecal mass deposited by a larva of Gallaba kirkpatricki sp. nov.; 14. Distribution of Gallaba constellata sp. nov.; 15. Distribution of Gallaba kirkpatricki sp. nov..