Pectinivalva (Menurella) acmenae Hoare

Hoare, Robert J. B. & Nieukerken, Erik J. van, 2013, Phylogeny and host-plant relationships of the Australian Myrtaceae leafmining moth genus Pectinivalva (Lepidoptera, Nepticulidae), with new subgenera and species, ZooKeys 278, pp. 1-64 : 37-39

Pectinivalva (Menurella) acmenae Hoare sp. n.

Material examined.

Holotype. ♂, 35.37S, 150.16E, 1 km SE of East Lynne, Kioloa State Forest, N.S.W., Acmena smithii , emg. 12.x.1995, R.J.B. Hoare. Paratypes. 3♂, 3♀, same data as holotype, emg. 10-21.x.1995; 2♂, 36.19S, 150.03E, Mt Dromedary, N.S.W., emg. 22, 24.x.1995, R.J.B. Hoare, E.S. Nielsen and M.J. Matthews, genitalia slides 10213, 11242 (anic); 2♂, 28.42S,153.37E, Broken Head NR, N.S.W., 13.vii.2000, emg. 15-18.viii.2000, Acmena smithii , R.J.B. Hoare, C. van den Berg, bred in NL, slide EJvN3541 (rmnh).

Description.

Male (Fig. 12). Wingspan 4.5-5.5 mm. Head: frontal tuft ferruginous; collar inconspicuous, consisting of white, grey-tipped scales; eyecaps anteriorly white, posteriorly shining grey with bluish reflections; antennae shining dark grey, whitish beneath, ca. 35 segments. Thorax, tegulae and forewing uniform shining dark grey with strong blue reflections; an inconspicuous tornal spot consisting of a few white scales; cilia dark grey. Hindwing unmodified, pale grey; cilia pale grey. Under side: forewing grey with faint brassy reflections; hindwing grey. Abdomen shining dark grey; anal tuft inconspicuous, dark grey.

Female (Fig. 13). Wingspan 5.2-5.6 mm. Similar to male, but antenna with 23-25 segments, and forewing rather broader. Wing venation as in Fig. 36. Abdominal tip not as broad and ‘square’ as in females of other Pectinivalva spp.

Male genitalia(Figs 52-54, 66). Capsule ca. 425 μm long, forming a narrow triangle. Anterior edge of vinculum excavated in a half-oblong. Tegumen rounded, with ventral extensions on each side overlapping lateral arms of gnathos. Uncus rectangular, bilobed, lobes slightly produced, with 3 setae on each. Gnathos central element long, reaching just beyond uncus, ending in small swelling. Valva (Fig. 53) ca. 210 μm long, squarish, more rounded caudally and produced into a short point at exterior corner of apex; apical ½ with numerous spine-like setae on dorsal surface; pectinifer consisting of ca. 18 spine-like elements. Long sublateral processes present. Juxta a weak subcircular plate. Aedeagus (Figs 54, 66) ca. 510 μm long, a curved spine arising towards apex on left, a shorter spine to right of this one, a third spine in line with second and anterior to it. Vesica basally with cathrema surrounded by a field of many broad, short cornuti; a separate field of ca. 9 long narrow cornuti above opening of ejaculatory duct.

Female genitalia(Fig. 77, 92-94). Total length ca. 760 μm. T9 prominent, with a group of 5-6 setae on each side. Apophyses anteriores rather narrow, curved inwards; apophyses posteriores narrow, straight, approximately equal in length to anteriores. Lateral sclerotizations of vestibulum strongly developed, forked, the bifurcations diverging widely, anterior pair blunt, posterior pair pointed. Ductus spermathecae with 4½ convolutions. Posterior part of corpus broad, folded, without markings; anterior part rounded, with rows of inconspicuous pectinations; signum consisting of broken linear sclerotization surrounded by oval sclerotized ring with blunt dentitions.

Larva. Green. Length of head ca. 440 μm; width ca. 350 μm. Thorax: prothoracic sternite in shape of Y with expanded base (Fig. 113); an additional small roundish sclerite on each side of this and antero-dorsal to SV and V group of setae. Chaetotaxy and spinosity: T2 with 11 pairs of setae (L3 present); otherwise as described for subgenus Casanovula . Anal rods distinctly forked posteriorly.

Biology.

Host plant: Syzygium smithii (Poir.) Nied. ( Myrtaceae ) (formerly Acmena smithii ), common lilly pilly. Egg: almost invariably on upperside, usually near leaf margin. Mine (Fig. 120): a long, very narrow contorted gallery, filled with brown frass apart from irregular crenulations along mine edge; exit-hole on underside, a semicircular hole. Cocoon: reddish brown. Occupied mines were collected on 30 July and 3 August.

Diagnosis.

This is the one of three known species of Pectinivalva in which the forewings have a bluish lustre but no transverse fascia. The others are Pectinivalva xenadelpha and Pectinivalva quintiniae , both described and diagnosed below. There is an undescribed Australian species of Stigmella which sometimes occurs together with Pectinivalva (Menurella) acmenae , and in which the forewings are similarly unicolorous dark blue; however, the Stigmella species is distinctly larger (wingspan 6-8 mm), and has a collar consisting of white lamellate scales; its larva is a leaf-miner on Baloghia inophylla (G. Forster) P. Green ( Euphorbiaceae ).

Distribution.

New South Wales. Vacated mines probably of this species were seen abundantly along the coast near Manley, Sydney.

DNA barcode.

RMNH.INS.23541, Genbank KC292474.

Derivation.

The specific name is derived from the former host-plant genus, and is a noun in the genitive. Because the moth is referred to under this manuscript name in the first author’s unpublished thesis, we have chosen to retain it for consistency, in spite of the change in classification of the host-plant.

Remarks.

The host-plant genus of Pectinivalva (Menurella) acmenae , Syzygium , is not closely related to other myrtaceous hosts from which Pectinivalva species have been reared in Australia, and belongs to the tribe Syzygieae ( Wilson et al. 2005, Biffin et al. 2006). Vacated mines on Syzygium ingens (F.Muell. ex C.Moore) Craven & Biffin (= Acmena brachyandra ) in Lamington National Park have tentatively been identified as this species (Appendix 2 and online Appendix 3).