Pectinivalva (Menurella) tribulatrix Van Nieukerken & 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 : 42-47

Pectinivalva (Menurella) tribulatrix Van Nieukerken & Hoare sp. n.

Material examined.

Holotype. ♂, Cape Tribulation, Queensland, [UTM: 55K CC365219], la. 23.vii.2004, [coastal rainforest], emg. 8.ix.2004, Rhodomyrtus macrocarpa , E.J. van Nieukerken, RMNH/EvN no 2004017, genitalia slide 18721 (anic) (= EvN 3962). Paratype. ♀, same data as holotype, genitalia slide EvN 3963 (rmnh).

Additional material: many leafmines from type locality, and 2 km south.

Description.

Male (Fig. 17). Wingspan 3.5 mm, forewing length 1.5 mm. Head: frontal tuft yellow to ferruginous, collar white; eyecaps basally white, exteriorly grey; antennae grey, 25 segments. Thorax and forewing entirely shining grey fuscous, cilia-line indistinct. Hindwing basally wide, grey, with androconial pocket in basal half; cilia grey. Underside: forewing and hindwing dark brown. Abdomen grey brown, with small white anal tufts.

Female (Fig. 18). Wingspan 3.2 mm, forewing length 1.4 mm. Head: as male, but eyecaps shining white, no grey, antennae with 17 segments. Coloration as male, but hindwing narrower, grey. Abdomen shining dark grey, wide blunt abdominal tip.

Male genitalia (Figs 70-72). Capsule ca. 235 μm long, ovoid. Anterior edge of vinculum with shallow excavation. Tegumen rounded, without ventral extensions. Uncus triangular, slightly indented in middle, lobes with ca. 3-4 setae on each. Gnathos central element long, not reaching beyond uncus, parallel edges, rounded tip. Valva ca. 190 μm long, reaching well beyond tegumen, strongly curved; medial edge slightly excavated and ending in obtuse angle; pectinifer consisting of 15-16 broad, blunt elements; dorsal surface towards apex with long setae. Sublateral processes short. Juxta not visible. Aedeagus (Fig. 72) ca. 280 μm long; tubelike sclerite associated with cathrema ca 2/3 aedeagus length, anteriorly bilobed; vesica otherwise with a few small cornuti.

Female genitalia (Fig. 101-103). Total length ca. 335 μm. T9 produced on each side into prominent anal papillae, each with a group of 7 setae. Apophyses anteriores moderately narrow, curved inwards; apophyses posteriores narrow, straight, longer than anteriores. Lateral sclerotizations of vestibulum strongly developed, forked, the bifurcations diverging widely. Ductus spermathecae with 6 convolutions. Corpus small, about as long as wide, folded, covered with many pectinations; signum of concentric bands of fence-like spinules, indistinct.

Larva. Green. Fieldnotes state that it feeds with dorsum upwards, which may be incorrect. Larva not preserved.

Biology.

Host-plant: Rhodomyrtus macrocarpa Benth., finger cherry ( Myrtaceae ). Many mines and three larvae were collected on the ca. 20 cm long leaves of seedling shrubs. Egg: on either side of leaf. Mine (Fig. 124): a narrow, long gallery, either completely meandering, or partly straight and following a major vein; frass black, broken and dispersed over total gallery width, not leaving clear margins; edges of gallery not straight, irregular; exit-hole on underside, a semicircular to oval hole. Cocoon reddish brown. Occupied mines have been collected on 22 July.

Diagnosis.

One of the smallest Pectinivalva species we know, recognised by unmarked greyish fuscous wings, grey edged scape in male and androconial pocket on male hindwing.

Distribution.

Northern Queensland, Cape Tribulation.

DNA barcode.

RMNH.INS.23962 (holotype), Genbank KC292484 and RMNH.INS.23963, Genbank KC292485, identical.

Derivation.

The species name is a noun in apposition, from the Latin tribulare, to press: hence tribulatio, distress, trouble, tribulatrix, one who causes trouble. It refers partly to the type locality (Cape Tribulation), and partly to difficulties the authors encountered in identifying the hostplant.

Remarks.

This species stands out from its relatives amongst the ‘derived’ species of Menurella (those with broad tooth-like pectinifer elements) in its hostplant Rhodomyrtus , which belongs to the tribe Myrteae; other members of this group feed on Eucalypteae.

Keys to the subgenera of Nepticulidae known from Australia

The keys presented here are only intended for the identification of nepticulid specimens taken in Australia, and will not necessarily work for material captured elsewhere. They are based on the extensive collection of Nepticulidae in ANIC, with associated larval material. Although the keys should work for all Australian nepticulids so far known, it should be noted that our knowledge of the fauna is still very incomplete and there may possibly be species which will key out incorrectly or not at all.

Key to adults, based on external characters and wing venation

1 Two species of Pectinivalva (Menurella) key out here: Pectinivalva (Menurella) acmenae and Pectinivalva (Menurella) quintiniae .

2 One undescribed species of Pectinivalva (Casanovula) lacks a fascia and keys out here.

Key to adults, based on male genitalia

3 One undescribed Stigmella species from South Australia, which has a gnathos with a single central element, keys out here.

Key to adults, based on female genitalia

4 Two species of Pectinivalva (Menurella) key out here: Pectinivalva (Menurella) acmenae and Pectinivalva (Menurella) quintiniae .

5 No females of Trifurcula have yet been captured in Australia, and the distinction used here is based on Holarctic members of the genus (see Johansson et al. 1990).

Key to the larvae

6 No constant morphological differences have been found between larvae of Pectinivalva (Casanovula) and those of Pectinivalva (Menurella) .

7 No larva of Trifurcula has been found in Australia, and the distinction used here is based on the description of European species in Johansson et al. (1990).