Polka commoni De Prins, Sruoga & Zwick, 2025

Prins, Jurate De, Hartley, Diana, Sruoga, Virginijus, Nicholls, James, Wallace, Jesse & Zwick, Andreas, 2025, Diversity of Australian Ornixolinae (Lepidoptera: Gracillariidae) with taxonomic and nomenclatural acts within the related taxa (Acrocercopinae and Gracillariinae) based on the evidence of museomics, bionomics, and mitogenomics, Zootaxa 5616 (1), pp. 1-340 : 303-305

Polka commoni De Prins, Sruoga & Zwick , sp. nov.

( Figs 632–635, 636)

Type locality: Australia, New South Wales, Batemans Bay.

Type specimens: Holotype ♀ ( Fig. 632): [labels verbatim] [1] Depot Beach/ 16 km NE of/ Batemans Bay /N. S.W. [New South Wales]/28 Dec.[ember] 1975/ I. F.B. Common. DNA sample NULT023611, genitalia slide ANIC 6297 , ANIC Acc. no 31 085629, in ANIC (Canberra).

Paratypes 2 specimens: Paratype 1(♀): New South Wales, Church Point , 33.6458°S 151.2841°E, 03-05-1959, leg. Common I.F.B. Paratype 2(♀): the same collecting data as for paratype 1, in ANIC (Canberra) .

Type depository: Australian National Insect Collection, Canberra, Australian Capital Territory, Australia.

Diagnosis: Highly distinctive species with the dark ochreous ground colour of forewings with a light pink lustre and two bright yellow spots, one at sub-apical part on the costal margin, the second at mid the dorsal margin of the forewing. Very easily diagnosable based on external habitus characters. Female genitalia are also highly diagnostic due to a huge signum occupying almost entirely the wall of the corpus bursae. Mitogenomic data are diagnostic as well.

Description: Wingspan ca. 6.0– 6.2 mm; length of the forewing 2.8–3.1 mm ( Fig. 632).

Head: vertex covered with pressed dark ochreous with strong copper shine piliform scales; occiput with two rather small tufts of short dark ochreous scales directed posteriorly; frons smooth covered by pressed dark ochreous with rather strong pink shine scales, labial palpus short, erected, matte, light ochreous with dark ochreous apex; labial palpus light ochreous, significantly lighter than frons, upturned, darker at apical part. Antenna ochreous with intermixture of dark fuscous at dorsal side; pedicel shorter and thicker than the second flagellomere, dark ochreous; scape straight tube-shaped, enlarged, as large as ca. three flagellomeres, dark ochreous, with strong copper shine, pecten not perceptible.

Thorax ( Fig. 632): dark ochreous with pink shine, tegula concolourous with thorax; forewing slightly narrowing at apical part; ground colour solid dark ochreous, two, bright, eye-catching spots are present on each forewing, at sub-apical part on costal margin and at mid part on dorsal margin; apical spot absent, apical line absent, fringe at apex, termen and tornus is dark ochreous, significantly darker than at dorsal margin. Hindwing narrow, with sharp apex, dark brown, with light bronze shine, fringe is much lighter than the colouration of forewing of median length, light ochreous, matte. Forelegs dark ochreous, mid tibia strongly thicken, dark ochreous, covered with long piliform scales, tibial spurs dark ochrous, mid tarsus lighter is colouration than tibia, with light bronze shine; hind tibia copper shining, bearing a row of erect stout scales, hind tarsus unicolourous with strong bronze metal shine.

Abdomen ( Fig. 635): dorsally brown fuscous with metal shine, ventrally sternites of lighter shading with stronger metal lustre. Abdominal opening broad, arc-shaped, margins of abdominal opening on sternum II broadly and strongly sclerotised, especially lateral and anterior margins on sternum II, posterior corners of abdominal opening gently rounded; ventral crossing joint sclerotised only at lateral parts; the ventral joint of abdominal opening is doubled by a sclerotised anterior margin of abdominal plate that is slightly convex in the middle; sternal apodemes not developed; tergal apodemes follow the lateral margin of abdominal opening, slightly bent, slender with sharp apices, enter the mid of sternal plate; abdominal segments without any sclerotisations, abdominal cuticle tuberculose.

Male genitalia: No data.

Female genitalia ( Figs 633–634): Papillae anales strongly flattened and fused, covered with setae of different lengths, shorter in mid part and longer, erect, sharp at the lateral sides. Apophyses posteriores with broad basal part, anterior part thick with blunt apices, entering the mid sector of segment VIII. Segment VIII, moderately melanised, carries a semi-circular sclerotised ring of the bases of apophyses anteriores; the anterior part of apophyses anteriores ca. 2× longer than apophyses posteriores; apophyses anteriores are slender, with sharp apices that reach the mid sector of segment VII. Sterigmatic sclerotisations on sternum VII absent. Ostium bursae opens at sub-posterior part of sternum VII; antrum small cup-shaped with sclerotised margins, colliculum long, extending segment VII, well-sclerotised; ductus bursae long, 3× longer than the length of the segment VII, broad; the distinction between ductus bursae and corpus bursae is strict. Corpus bursae small, oval shaped with wrinkled bursal wall; signum is huge occupying a full surface of corpus bursae, signum oval in shape with melanised furrows and two sclerotised appendages at the joint between corpus bursae and ductus bursae.

Individual variation: Some variation is observed in the shape and size of two yellow patches. However, their position on the forewing is stable. The holotype bears a tiny additional spot at the apex of the forewing that is absent in both paratypes. This character is considered part of the intraspecific variation.

Bionomics: No data.

Mitogenomic data: The single mitochondrial genome sequence obtained from the holotype is very distinct from all other sequences and placed with maximum support in all analyses as a sister to all other Gracillariinae sequenced. Distribution: Known from two localities: Australia: New South Wales: Batemans Bay, and Church Point. Etymology: The specific epithet is formed from the personal name of the collector I.F.B. Common. It is a noun in the genitive case that has been latinised and it is formed in accordance with the rules of Latin grammar (Art. 31.1.1.).

List of taxa treated in the current study