Holocacista varii (Mey, 2011) Mey, 2011

van Nieukerken, Erik J. & Geertsema, Henk, 2015, A new leafminer on grapevine and Rhoicissus (Vitaceae) in South Africa within an expanded generic concept of Holocacista (Insecta, Lepidoptera, Heliozelidae), ZooKeys 507, pp. 41-97 : 59-61

Taxon classification Animalia Lepidoptera Heliozelidae

Holocacista varii (Mey, 2011) comb. n. Figs 5, 6, 59-64, 67-69, 89, 90, 104, 112, 114, 116

Antispilina varii Mey, 2011: 156. Holotype ♂ RSA, Cape Town, 26.3.1954, bred from Pelargonium cucullatum from slopes of the Table Mtn., Vári Ac. No. 1047, leg. 4.3.1954, L. Vári, genitalia slide Mey (TMSA) [not examined].

Differential diagnosis.

Holocacista varii is the only species similar to Holocacista capensis that occurs probably commonly in the natural habitats near the grape growing areas of Western Cape and thus could potentially be confused with it. It is distinctly larger, and the forewings are more shining bronze than those of Holocacista capensis . Moreover, the male and female have a complete fascia at 1/3 from forewing base that is not narrower at the costa and the antennae are not ringed. In male genitalia, Holocacista varii lacks the larger spines on the phallocrypt, and has a more developed juxta; further, the dorsal row of spines on the tegumen is characteristic and the shape of the transtilla differs. The female genitalia have more elaborate sclerotisations, and the apophyses are longer.

Redescription.

Male (Fig. 5). Head face and vertex covered with appressed, metallic, pale-bronze scales. Palpi porrect, white; base of proboscis covered with white scales. Antenna with ca. 20 segments, uniform bronze brown, scales on underside all white. Legs grey, tarsi mostly yellowish white, especially on underside. Thorax and forewings grey brown with some bronze lustre, with silver-white patterning; an oblique fascia at 1/4, hardly narrower at costa; a slightly triangular dorsal spot at 1/2, not reaching middle of wing; a triangular or squarish costal spot just beyond middle; fringe line not very distinct, demarcating scales not conspicuously dark tipped. Terminal fringe silvery white. Hindwings pale grey. Underside of wings fuscous. Abdomen lead grey, including vestiture on external genitalia.

Female (Fig. 6). Antenna with ca. 19 segments. Colour pattern different from male: scales more uniformly bronze brown, with strong lustre, and contrasting silvery-white pattern.

Measurements. Male: forewing length 2.4-2.8 mm (2.5 ± 0.1, 6), wingspan: 5.0-5.7 mm. Female: forewing length 2.1-2.6 mm (n=3), wingspan 4.5-5.6 mm.

Male genitalia (Figs 59-64, 104, 112, 114). Total length vinculum + tegumen ca. 670 µm. Vinculum (S IX) long, reaching anterior margin of segment VI. Tegumen (Figs 60, 61, 114) well sclerotised, with medial, blunt posterior projection, with several setae; tegumen dorsally with a transverse keel with many strong spines in posterior direction. Valva (Fig. 63) narrow, basally wider, apex blunt, with stalked pectinifer halfway along inner margin, pecten comprising 7 or 8 blunt sensilla. Valva length (without transtilla) ca. 265 µm. Transtilla (Figs 64, 112) with relatively long sublateral processes and medial spatulate posterior process, indented posteriorly. Juxta (Fig. 62) well developed, split into an elongate process ventral to phallus and a furcate process dorsal to phallus. Phallus (Figs 62, 104) long and narrow, ca. 540 µm long. Phallocrypt (manica) slightly spinulose posteriorly, no strong spines present. Phallus in lateral view a distinctly-curved outer tube with ventrally-curved appendix, the latter almost straight, ca. 120 µm long (measured as curve).

Female genitalia (Figs 67-69). Length of anterior apophyses ca. 935 μm (n=1), posterior apophyses 1020 μm (n=1). Oviscapt with 4 or 5 cusps at either side (Fig. 69). Ductus spermathecae with many wide convolutions, spermathecal papilla with circle-shaped sclerotisation, other elaborate sclerotisations in vestibulum.

Biology.

Host plants. Geraniaceae ; most commonly found on Pelargonium cucullatum (L.) L’Hérit., a common plant in Fynbos of Cape Peninsula and the western part of the Western Cape; single records on Pelargonium panduriforme Eckl. & Zeyh., Pelargonium hispidum Willd. and Pelargonium citronellum J.J.A. Van der Walt.

Leafmines (Figs 89-90). The egg is inserted at any place of the leaf underside, usually not far from a vein. The mine starts towards a vein and then follows the vein as a narrow gallery of ca. 2 cm, eventually rather suddenly enlarging into a more or less triangular or elongate blotch, usually after the mine makes a turn of 180°. In thin leaves the blotch can be very elongated. The frass in the early mine is a narrow black line, in the blotch the frass is typically clumped near the entrance. Mines occur either singly or with a few together on one leaf. The larva cuts out an elliptic case of about 3.4-3.7 mm long × 1.6-2.2 mm wide. The larva probably descends with its cocoon into leaf litter before pupation.

Voltinism. Larvae are found between mid-September and April, and are apparently absent in winter; adults usually emerge between 3-6 weeks after collecting the larvae, suggesting there are multiple overlapping generations. The specimen from Worcester (October) is the only record of an adult taken in the wild.

Distribution

(Fig. 116). South Africa: Western Cape, Eastern Cape (new record). The species is abundant on Table Mountain and in the Cape Peninsula, but it is here also recorded from other Fynbos localities around Stellenbosch and Worcester, and Vári also reared it from Zuurberg Pass in Eastern Cape, so we assume a wide distribution in Western and Eastern Cape.

DNA barcode.

We barcoded four specimens (three from Table Mountain, one from Stellenbosch), with a maximum intraspecific distance of 1.55%, within the same population on Table Mountain. The BIN is BOLD:ACG8941.

Remarks.

In the original description Mey (2011) mentioned that the valval pecten has 13-15 spines, a number that we cannot confirm from the few specimens studied. He further considered the phallus appendix as a cornutus. This appendix, however, is not attached to the vesica, but is an unmovable extension of the phallic tube. Mey (2011) placed this species in Antispilina on the basis of its venation, overlooking the fact that Holocacista has the same venation. Antispilina is a small Palearctic genus, feeding on Polygonaceae , with some new species in the course of description (B.W. Lee et al. in preparation). The placement of this species in Holocacista , which is diverse in Africa, makes much more sense. Possibly the ancestor of Holocacista varii shifted hosts from Vitaceae to Pelargonium .

Many of the specimens listed under material have only been briefly examined by EvN during his visit to the Ditsong Museum, hence the absence of indication of sex.

Material examined.

Eastern Cape: 1 adult, Zuurberg Pass, south slopes, 22.iii.1954, 11 mines, Pelargonium sp., 1 adult emerged 20.iv.1954, L. Vári (TMSA). Western Cape: 5 adults, Bloubergstrand, 3.x.1974, Ac. no. 3308, leafmines on Pelargonium , emerged 26-30.x.1974, L. Vári (TMSA); 2 adults, ibidem, 13.x.1975, Ac. no. 3496, leafmines on Pelargonium , emerged 14.xi.1975, L. Vári (TMSA); 6 adults, Cape of Good Hope Nature Reserve, 26.x.1966, Ac. no. 2851, leafmines on Pelargonium , emerged 21-23.xi.1966, L. Vári (TMSA); 8 adults, ibidem, Ac. no. 288527.x.1967, emerged 20-22.xi.1967, L. Vári (TMSA); 4 adults, Cape Peninsula, Bakoven, 29.x.1975, Ac. no. 3499, leafmines on Pelargonium , emerged 17-19.xi.1975, L. Vári (TMSA); 5 adults, Cape Peninsula, Hout Bay, 11.xi.1954, Ac. no. 1357 leafmines on Pelargonium cucullatum , emerged 7-21.xii.1954, L. Vári (TMSA); 2 adults (paratypes), ibidem, 14.ix.1966, Ac. no. 2846, emerged 21.xi.1966, L. Vári (TMSA); 10 adults (paratypes), Cape Peninsula, nr. Muizenberg, Steenberg, 10.xi.1979, Ac. no. 3764, leafmines on Pelargonium , emerged 15. xi– 10.xii.1979, L. Vári (TMSA); 1♂, 1♀, 1 adult (paratypes), Cape Town, Kirstenbosch, 17.xi.1954, Ac. no. 1365, leafmines on Pelargonium cucullatum , emerged 11-14.xii.1954, L. Vári (MHUB, TMSA); 1 adult, ibidem, emerged 5-29.xii.1954, A.J.T. Janse (TMSA); 2 adults (paratypes), ibidem, 14.ix.1962, Ac. no. 2535, emerged 1-17.x.1962, L. Vári (TMSA); 1♂, 1♀, ibidem, 23.xi.2014, leafmines on Pelargonium citronelium , emerged 11.xii.2014, L. Torrance & H. Geertsema (USEC); 1♂, 1♀, ibidem, 23.xi.2014, leafmines on Pelargonium cucullatum , emerged 11-14.xii.2014, L. Torrance & H. Geertsema (USEC).

6♂, 4♀ (paratypes), 1 adult, Cape Town, slopes Table Mt., 4.iii.1954, Ac. no. 1047, leafmines on Pelargonium cucullatum , emerged 26. iii– 3.iv.1954, L. Vári (TMSA); 9 adults, Noordhoek, leafmines on Pelargonium , pupa 10-14.v.1984, emerged 28-31.v.1984, H. Geertsema (TMSA); leafmines, Stellenbosch, Botanical Garden, 122 m, 27.i.2013, EvN2013032, leafmines on Pelargonium panduriforme , E.J. van Nieukerken (RMNH); 1 larva, ibidem, 27.i.2013, EvN2013033, leafmines on Pelargonium hispidum , E.J. van Nieukerken (RMNH); 3 larvae, Stellenbosch, Jonkershoek, 390 m, 18.i.2013, EvN2013017, leafmines on Pelargonium cucullatum , E.J. van Nieukerken & H. Geertsema (RMNH); 3♂, 4♀, 3 larvae, Table mountain NP, Cecilia, nr Klaasenskop, 385 m, 19.i.2013, EvN2013022, leafmines on Pelargonium cucullatum , emerged 11-22.ii.2013, E.J. van Nieukerken (RMNH); 1♂, 1♀, 1 larva, Table mountain NP, Cecilia, parking lot, 180 m, 19.i.2013, EvN2013024, leafmines on Pelargonium cucullatum , emerged 24. i– 12.ii.2013, E.J. van Nieukerken & H. Geertsema (RMNH); 1♂, Worcester, Fairy Glen, 15-19.x.1966, L. Vári & Potgieter (TMSA).

Other material.

Leafmines, observation, Western Cape, Ashton, 2014, L. Torrance & H. Geertsema.