Diphtheroptila crotonella 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 : 101-103

Diphtheroptila crotonella De Prins, Sruoga & Zwick , sp. nov.

( Figs 144, 145, 161–163, 192–195, 219–221, 238–240, 257, 266, 275, 638)

Type locality: Australia, Queensland, Kuranda.

Type specimens: Holotype ♂: [labels verbatim] [1] Australia Q[Queensland]/Kuranda/nr. Cairns/em.[emerged] 12.V.[May]2005/ T. & M. Kumata [2] Host 6089/ Croton sp. , DNA sample NULT025062, genitalia slide ANIC 6216 , ANIC Acc. no 31 085544, in ANIC (Canberra).

Paratypes 13 specimens, with 2 lose separate abdomens: Paratype 1: without abdomen, same collecting data as for the holotype, except the date 07 May 2005. Host 6089 Croton sp. ( Euphorbiaceae ). Paratype 2(♀): same collecting data, except the date 09 May 2005. Paratype 3(♀): same collecting data. Paratype 4: without abdomen, same collecting data, except the date 08 May 2005. Paratype 5: without abdomen, same collecting data, except the date 06 May 2005. Paratype 6: without abdomen, same collecting data. Paratype 7(♀): same collecting data. Paratype 8(♂): same collecting data, except the date 06 May 2005, DNA sample NULT025309, genitalia slide ANIC 6218, ANIC Acc. no 31 085583. Paratype 9(♀): right antenna broken, same collecting data, except the date 09 May 2005, DNA sample NULT025187, genitalia slide ANIC 6217, ANIC Acc. no 31 085584. Paratype 10(♀): Queensland, 16.49S 145.38E, Kuranda em.[erged] 05 March 1998, leg. T. & M. Kumata, Host 5963, DNA sample NULT025521, genitalia slide ANIC 6206, ANIC Acc. no 31 085575. Paratype 11: without abdomen, same data. Paratype 12(♀): Queensland, Kuranda, Cairns , em.[emerged] 23 December 1999, leg. T. Kumata, Host 6215 Glochidion sp. , DNA sample NULT025293, genitalia slide ANIC 6210, ANIC Acc. no 31 085579. Paratype 13(♂): same collecting data, except the date 22 December 1999, DNA sample NULT025415, genitalia slide ANIC 6211, ANIC Acc. no 31 085580, in ANIC (Canberra).

Specimen not included in the type series: without abdomen, Queensland, Kuranda, Cairns , em.[emerged] 22 December 1999, leg. T. Kumata, Host 6215 Glochidion sp. , in ANIC (Canberra).

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

Diagnosis: This species is the closest to Diphtheroptila nix sp. nov. externally, by bionomics and by mitogenomics, and forms a complex of closely genetically, morphologically and biologically related species. In general, Diphtheroptila crotonella sp. nov. shows more variability in specimen size than D. nix sp. nov., however, it should be kept in mind that a longer series of type specimens is available for D. crotonella sp. nov. and D. nix sp. nov. type specimens were collected at the same spot, in the same period of the year, under the same micro climatic conditions. For tiny diagnostic differences in external morphology see the diagnosis and description of D. nix sp. nov. Internal morphology is highly diagnostic: shape of valvae, sclerotisation of ventral margin of valvae and especially the presence of eye catching angulated sclerotised structure on costal margin of valvae in D. crotonella sp. nov. leave no doubt about the distinctiveness of these two new species occurring simultaneously and feeding on the same host plant. Mitogenomic data visualize the close relationship of both species but leaves no doubt that two separate species-group taxa are involved.

Description: Wingspan ca. 5.0–7.0 mm; length of the forewing 2.2–3.3 mm ( Figs 144, 145).

Head ( Figs 161–163): vertex smooth, unicolourous, ochreous beige, covered with long piliform scales, directed anteriorly; occiput with two lateral tufts of radially directed piliform scales, concolourous with vertex. Frons ground colour concolourous with vertex, ochreous beige, speckled by small narrow stripes, two long brushes hang at lateral side of frons, next to eyes. Maxillary palpus very short, porrect, ochreous with ochreous fuscous apex. Labial palpus as long as ca. 2.5× diameter of the eye, ochreous, with impressive tuft of hanging dark fuscous piliform scales of different lengths, terminal palpomere glabrous, fuscous from outer side, light ochreous from inner side. Proboscis ochreous, strongly rolled. Antenna slightly (ca. 1/4) longer than forewing, chocolate brown dorsally ochreous posteriorly, consisting of numerous tightly pressed, tiny, thin, piliform scales with light apices, ventrally ochreous beige; pedicel slightly shorter than the following flagellomere, dark ochreous; scape ochreous with two dark chocolate ochreous stripes observed from the anterior view, these stripes are prolongations of antennal pattern which from anterior view looks dark chocolate brown with bright light ochrous line running along antennal length; a few light beige pecten of different lengths hang at the base of pecten.

Thorax ( Figs 144, 145, 192–195): and tegula ochreous fuscous, concolourous with the ground colour of vertex. Forewing narrowly elongated, costal and dorsal margins run parallel, apex gently rounded, ground colour dark fuscous ochreous, shading is even darker at dorsal half of forewing, forewing with light ochreous narrow but distinct linear markings. Four groups of linear markings consisting of three except the apical one are present on the forewing: i) three short oblique stripes toward apex are present on the sub-basal part of the dorsal margin with a facing clear spot on the coastal margin; ii) three oblique complete or interrupted non-contrastive linear fascia at mid of forewing; iii) the group of angulated linear fascia at sub-apical part of forewing followed by iv) a group of two arched lines finalizing the pre-apical ornamental part of forewing; apical spot round, black, distinctly preceded by a narrow short ochreous stripe neighbouring the black apical spot; apical line narrow, fine with small interruptions. The fringe line is double, most expressed at tornal area, consisting of prolonged scales with dark fuscous bases and black apices. Fringe ochreous grey, with golden shine, with the darkest shade at sub-basal area, shorter at tornus, the longest at sub-apical part and again shortening towards base of forewing. Hindwing narrow, elongate, sharply pointed, ground colour fuscous with dark ochreous shading, fringe long, ca. 6× longer than the width of hindwing at the base, significantly lighter in shading than the colour of hindwing with bright golden shine, the longest piliform scales hanging at the base of the dorsum of the hindwing. Fore femur and fore tibia fuscous dorsally and light fuscous ventrally, tarsomere I dark fuscous, almost black, the rest of the tarsomeres light fuscous ochreous with dark bases and apices, tip of fore leg dark fuscous; mid femur and tibia ochreous fuscous with three prolonged oblique dirty ochreous stripes, tarsomeres dirty ochreous with dark fuscous bases and apices, tip of mid leg fuscous ochreous; hind femur ochreous, hind tibia fuscous, covered with mid-sized spines of similar length; median spurs long, as long as about 2/3 of tibia length, light grey, apical spurs slightly shorter than tarsomere I, fuscous at base and dirty ochreous at apical 2/3, tarsomeres dark fuscous, with light grey or ochreous apices, the tip of hind tarsus light grey.

Abdomen ( Figs 192–195, 257, 266): Tergites I–III ochreous with golden shine, the rest of tergites ochreous grey, sternites light grey, with obvious five oblique dark brown stripes on lateral sides of abdomen. Abdominal opening broadly triangular with gently rounded posterior corners, lateral margins of abdominal opening strongly sclerotised, double lined, ventral crossing joint with narrowly sclerotised anterior margin that borders ventral sclerotised plate; sternal apodemes initiating at the round corners of abdominal opening are of mid length, thin, slightly bent, approaching each other with their apical parts, entering anterior 1/3 of segment II, tergal lateral sclerotisations of the abdominal opening at a distance from each other, forming two supportive lateral triangular sclerotisations, that are very characteristic for this species. Tergal connection between left and right mirroring sides is the anterior margin of melanised plate; the initiating point of tergal apodemes is the sub-anterior joint on tergum I, tergal apodemes have two short appendages at bases, and form an arrow-shaped basal sclerotised structure; tergal apodemes thin, straight, slightly approaching each other, rather long, reaching beyond the mid part of tergum II; apical part of tergal apodemes sharp. Anterior margins of segments III–VII in males narrowly and finely melanised, segment VII with two ring-like androconial sclerotisations, posterior margin of segment VI in females with broad, diffuse but clearly observable sclerotisation.

Male genitalia ( Figs 219–221): Tegumen short, blunt with triangular uncus, short arms of uncus are fusing at the top; anal tube strongly protruding; valvae broad, the mid sector is the broadest part, gently tapering towards apex with broad round cucullus, ventral sub-apical margin densely setose, costal margin at sub-base with angulated, rather complex appendage; a narrow but sclerotised suture follows the costal margin of valvae; sacculus with narrow, but strongly sclerotised fold covered with tiny spiculae. Transtilla incomplete; the vincular lateral folds act as support; vinculum is strongly developed, U-shaped, consisting of two symmetrical rectangular plates with very clear suture in the mid of vinculum; saccus short but well developed, more or less triangular with equal lateral margins, crossed by mid-suture with protruding digitiform appendage with nicely rounded anterior part. Aedeagus ca. as long as valva, cylindrical, with gently rounded vesica, one curved cornutus at the main body of aedeagus, coecum semi round with one irregular small marking.

Female genitalia ( Figs 238–240): Papillae anales fused and strongly flattened, covered with long, thin, setae of different lengths; apophyses posteriores short, of mid thickness with sharp apices, terminating at posterior margin of segment VIII, segment VIII is short, weakly sclerotised; apophyses anteriores initiate at the posterior edge of segment VII, short, sharp, thin, with broad triangular apices; segment VII moderately sclerotised with two lobed or fused semicircular lamellae post-vaginalis and strongly sclerotised in several concentrical wrinkles lamella ante-vaginalis; ostium bursae opens at mid part of sternum VII, with conical antrum. Ductus bursae long broad, strongly sclerotised, of equal length along its main part, slightly puffed at the joint ductus bursae and corpus bursae with three sharp spines; corpus bursae long sac-shaped with wrinkled and melanised wall, a single sub-triangular signum with spiniform anterior part. Bulla seminalis rather big but about 3× smaller than corpus bursae with lightly but visibly sclerotised ductus seminalis that enters the enlarged part of ductus bursae.

Individual variation: the species is described based on rather long series of type specimens. A rather significant individual variation is observed in forewing pattern in shape, thickness and contrast of ornamental markings, especially linear markings can be interrupted, or in some parts only traceable.

Bionomics ( Fig. 275):This species feeds on an unidentified Croton species ( Euphorbiaceae ).This is the first confirmed record of a Diphtheroptila moth species feeding on plant family Euphorbiaceae . Diphtheroptila crotonella sp. nov. is not monophagous. It also feeds on Glochidion sp. ( Phyllanthaceae ), a usual host for Diphtheroptila species, and on an unidentified Euphorbiaceae plant. Herbarium number 5963. The mining period is at the end of December, early March and the beginning of May. Most probably D. crotonella sp. nov. has several generations per season.

Mitogenomic data: The species is maximally supported as sister to D. nix sp. nov. in all analyses ( Fig. 638).

Distribution: Known only from the type locality: Australia: Queensland, Kuranda.

Etymology: The specific name derives from the generic name of the host plant of the holotype of this species with a diminutive suffix - ella. It is a noun of feminine gender in apposition.