Oemona hirta (Fabricius)

(Figs 29 –38)

Saperda hirta Fabricius, 1775: 184. — Fabricius, 1792: 309.

O. hirta — Broun, 1880: 570; Sharp, 1886: 437; Broun, 1893: 1275; Hutton, 1904: 192; Aurivillius, 1912: 115; Hudson, 1934: 207; Blair, 1937: 262; Hosking, 1978; Clearwater, 1981; Scott, 1984: 58; Wang et al., 1998: 1360; 2002: 563; Wang and Shi, 1999: 60; 2001: 463.

Saperda villosa Fabricius, 1801: 320. — Hudson, 1934: 207.

Isodera villosa — White, 1846: 21. pl. 4, fig. 1; White, 1855: 331; Hutton, 1873: 164.

Oemona villosa — Sharp, 1886: 437; Broun, 1893: 1275; Hutton, 1904: 192; Blair, 1937: 262.

O. humilis Newman, 1840: 8. — Sharp, 1886: 436; Broun, 1893: 1274; Hutton, 1904: 192; Aurivillius, 1912: 116; Hudson, 1934: 207; Blair, 1937: 262 (synonymy).

Material examined

S. hirta. Holotype. Ψ, bearing a black edged label with handwritten Saperda hirta in black ink and a white label with printed Fab. Entom. P. and handwritten no. 189 n. s. (BMNH, Banks Coll.).

S. villosa. Holotype. Ψ, no data, bearing a label with handwritten type pinned at side (BMNH, Banks Coll.).

O. humilis. Holotype. ♂, bearing a red circular BM type label, a blue circular registration label with handwritten no. 63 – 44 (1863 – 44 material was collected by C. Darwin), a white label with handwritten Oemona humilis Newman, N. Zealand (Darwin), and a blue label with handwritten Oemona Newman, Entomologist 1.8, humilis Newman, l.c. New Zealand /C. Darwin (BMNH).

Other material. New Zealand: 54 ♂, 77 Ψ. ND: 1 Ψ, Spirits Bay, Northland, xi. 1967 (NZAC); 1 Ψ, Waipapa, 29.i. 1953 (NZAC); 1 Ψ, Kerikeri, larva in Macadamia tetraphylla, 09.ix. 1978 (NZAC); 1 ♂, Parua Bay, Whangarei, 05.i. 1927 (NZAC); 1 ♂, Ahipara Shipwreck Bay, 08.x. 1974 (NZAC); 1 ♂, Mangamuka, G. Hokianga, 09.i. 1927 (NZAC); 1 ♂, Waipoua Stm, 70m, malaise trap in forest clearing, 16–21.i. 1978 (NZAC); 1 ♂, Kaikohe, 08.xii. 1948 (NZAC); 1 ♂, Kaeo, 28.i. 1953 (NZAC); 1 ♂, Whangarei 13.iii. 1972 (WMNZ); 1 ♂, North Cape, 18.xi. 1967 (NZAC); 1 ♂, Pukenui Hills, 24.xii. 1944 (NZAC). AK: 1 Ψ, Islington Bay, Rangitoto I, 12.ix. 1976 (NZAC); 1 Ψ, Auckland, ex dead Hoheria sp. vi. 1939 as pupa (NZAC); 1 Ψ, Lynfield, 13.x. 1975 (NZAC); 1 ♂, Manukau, 19.xi. 1916 (NZAC); 1 Ψ, Tropicana Dr, Lynfield, 22.x. 1975 (NZAC); 1 ♂, as above but 23.ix. 1975 (NZAC); 1 ♂, as above but ex cut Parsonsia, 08.xi. 1975 (NZAC); 1 Ψ, Titirangi, xi. 1942 (NZAC); 1 Ψ, as above but 03.xii. 1949 (NZAC); 1 Ψ, Takapuna, 1912 (NZAC); 1 Ψ, Bayswater, 1913 (NZAC); 1 Ψ, Helensville, ex Cryptomeria japonica, x. 1982 (NZAC); 1 Ψ, Auckland, ex Xalara macrophyllum, 07.x. 1960 (NZAC); 1 Ψ, Onehunga, 24.xi. 1936 (NZAC); 1 ♂, as above but 10.x. 1936 (NZAC); 1 Ψ, Grafton Downs, 12.i. 1999 (LUNZ); 1 Ψ, Opononi, ex. Manuka (Leptospermum scoparium), 01.ii. 1912 (NZAC); 1?, Owairaka, 27.x. 1942 (NZAC); 1 ♂, as above but ex timber, 20.x. 1941 (NZAC); 1 Ψ, Mt. Albert, viii. 1916 (NZAC); 1 Ψ, Spraggs Bush, Waitakere Ra, 07.xi. 1976 (NZAC); 1 Ψ, Piha, 28.xii. 1940 (NZAC); 1 Ψ, Papatoetoe, attracted to light, viii. 1954 (NZAC); 1 ♂, Tawharanui North, vi. 1960 (NZAC); 1 ♂, Mt. Wellington, Auckland, 10.x. 1934 (NZAC); 1 ♂, Waiheke I, 21.xii. 1942 (NZAC); 1 ♂, Noises Is, Otata I, 12.xii. 1977 (NZAC); 1 ♂, as above but 05.ix. 1980 (NZAC); 1 ♂, Papakura, 20.xi. 1931 (NZAC). CL: 1 Ψ, Little Barrier I, 21–27.ii. 1976 (NZAC); 1 Ψ, Coromandel Forest Pk, 12.xi. 1978 (LUNZ); 1 ♂, 3 Ψ, Little Windy Hill, Great Barrier I, 220m, forest edge, malaise trap, 18.i– 21.ii. 2002 (AMNZ); 1 ♂, Kopu, Thames, 06.ii. 1968 (NZAC); 1 Ψ, as above but ex Avecinnia resinifera; 1 ♂, Little Barrier I, (NZAC); 1 ♂, Kopu, 25.ii. 1977 (NZAC). WO: 1 Ψ, Te Kauwhata, 15.ii. 1940 (NZAC); 1 Ψ, Hamilton (NZAC); 1 ♂, Hamilton, 16.xi. 1969 (NZAC); 1 ♂, Te Aroha, 1914 (NZAC); 1 ♂, Kaimai Range, 01.ii. 1922 (NZAC); 1 ♂, Tahuna Road, Morrinsville, 21.ii. 1995 (ARH). BP: 1 Ψ, L Rotoiti Res nr Rotorua, malaise trap in mixed podocarpus forest, 24–29.iii. 1978 (NZAC); 1 Ψ, Te Puke, 05.xii. 1975 (NZAC); 1 Ψ, Lake Rotoehu, 15.ii. 1979 (NZAC); 1 Ψ, 1 ♂, Te Rereauira, 20–24.xi. 1992 (LUNZ); 3 Ψ, as above but malaise trap in Nothofagus truncata forest; 1 ♂, as above but 26.ii–09.iii. 1993 (LUNZ); 2 ♂, Papatea, 19–30.x. 1992 (LUNZ); 1 Ψ, as above but malaise trap, mixed broadleaf/ podocarp forest, 18.x– 25.xi. 1992 (LUNZ); 1 ♂, L Rotoiti, 04.i. 1976 (NZAC); 1 ♂, 27km, W Rotorua Mamaku Plateau Galaxy Road, 6–11.iii. 1978 (NZAC); 1 ♂, Tauranga, i. 1972 (LUNZ). TO: 2 Ψ, 1 ♂, Forest Products Waituhi, 30.x. 1984 (FRNZ); 1 Ψ, Mt. Ruapehu, Chateau, Tongariro, 1067m, 28.xi. 1977 (NZAC); 1 Ψ, Taupo, 14.i. 1932 (NZAC); 1 Ψ, Oio, 20.i. 1936 (NZAC); 1 Ψ, Waiotapu (NZAC); 1 ♂, Whakapapa, 31.xi. 1965 (NZAC); 1 ♂, Raurimu, 21.xi. 1965 (NZAC). GB: 1 Ψ, Gisborne, 01.i. 1968 (LUNZ). TK: 1 Ψ, Mahoenui, 07.viii. 1962 (NZAC); 1 Ψ, Mt. Egmont, 29.ii. 1920 (NZAC); 1 ♂, as above but 1270m, 27.vi. 1980 (NZAC); 1 ♂, Dawson Falls, Mt. Egmont, 945m, 14–20.i. 1955 (NZAC); 1 ♂, Holly Hut, 914m, Mt. Egmont, 28.xi. 1975 (NZAC). RI: 1 Ψ, 1 ♂, Pohangina Valley, Totara Reserve, 29.xii. 1975 (NZAC); 2 Ψ, Mt. Wharite Ridge, Ruahine, Mts, O. colensoi foliage, 14.ii. 1966 (LUNZ); 3 Ψ, Mt. Wharite Ridge, light trap, 14.ii. 1966 (LUNZ). HB: 1 Ψ, Omaranui, Hawke Bay, 15.ix. 1970 (NZAC); 1 Ψ, Hawke Bay, bred from grape Robs, vii. 1941 (NZAC); 1 ♂, Hastings, light trap, 12.xii. 1939 (NZAC). WI: 1 Ψ, Palmerston North, 08.xii. 2002; 1 Ψ, Foxton, 1938 (NZAC). WN: 1 Ψ, Upper Hutt, 12.xii. 1978 (LUNZ). SD: 1 Ψ, Queen Charlotte Sd, Te Iro Bay, 21.i. 1992 (LUNZ); 1 Ψ, Queen Charlotte Sd, Bay of Many Coves, 4–31.i. 1992 (LUNZ); 1 ♂, as above but in house, 02.i. 1993 (LUNZ); 2 Ψ, Arapawa I., Te Iro Bay, on house at night, 05.i. 1992 (LUNZ); 1 ♂, as above but attracted to light at night, 21.xii. 1985 (LUNZ); 1 Ψ, Curious Cove, 15.xi. 1959 (NZAC); 1 ♂, Bulwer Station Pelorus Sounds, ii. 1975 (LUNZ); 1 ♂, Ship Cove, Marlb Snd, 29.xi. 1972 (NZAC). NN: 1 Ψ, Abel Tasman National Park, Totaranui, in building, 02.xi. 1981 (LUNZ); 1 Ψ, Nelson, 14.ix. 1930 (NZAC); 1 ♂, Nelson, 28.ix. 1955 (NZAC); 1 ♂, Wakefield, 01.xi. 1932 (NZAC); 1 ♂, Motueka, 06.ix. 1955 (NZAC); 1 ♂, Paturau, 02.iv. 1994 (CMNZ); 1 ♂, Waimangaroa, 1973 (LUNZ). KA: 1 Ψ, Oaro, 16.vii. 1966 (NZAC); 2 Ψ, Kaikoura, ex Cytisus proliferus, vii. 1980 (LUNZ). BR: 1 Ψ, Cape Foulwind, Okari River, swept roadside, 29.x. 1970 (LUNZ). WD: 1 Ψ, Hokitika, 10.i. 1971 (LUNZ); 1 Ψ, Okarito Beach, 01.iii. 1966 (NZAC); 1 Ψ, Copeland Valley, 20.xii. 1962 – 06.i. 1963 (NZAC). MC: 1 Ψ, Hinewai Reserve, Banks Peninsula, 520m, 09.xii. 1993 (LUNZ); 2 Ψ, 1 ♂, as above but malaise trap Quiet Stream, 390m, 09– 29.xii. 1993 (LUNZ); 1 Ψ, Mt Pleasant, Christchurch, in spider net in garden, 25.i. 2002, (LUNZ); 1 Ψ, McLennans Bush, 13.xii. 1958 (NZAC); 1 Ψ, Coopers Knob, 11.xi. 1934 (CMNZ). SL: 1 Ψ, Invercargill, (NZAC). No locality: 1 ♂, Spec. 39, bred from Citrus wood, 08.xi. 1949 (NZAC); 1 Ψ, Spec. 72, bred from Walnuts, 24.x. 1949 (NZAC); 1 Ψ, Spec. 51, bred from larva in Tonegranaia, 08.ix. 1949 (NZAC); 1 Ψ, bred from pupa in Albizia lophantha, 04.vii. 1949 (NZAC); 1 ♂, bred from apple wood, 27.ix–02.x. 1949 (NZAC); 1 Ψ, Spec. 172, bred from Solanum auriculatun, 28.xi. 1949 (NZAC); 1 Ψ, Spec. 80, bred from Loguat 16.ix. 1949 (NZAC); 1 Ψ, Spec. 89, bred from Cherry wood, 30.ix. 1949 – 03.x. 1949 (NZAC); 1 Ψ, 11.xii. 1926 (CMNZ); 1 ♂, ex from Albizia lophantha wood, 21.ix. 1949 (NZAC); 1 ♂, North Island, 10.xii. 1991 (LUNZ).

Redescription

Male (Fig. 29). Body length: 11.4–24.4 mm. Colour patterns. Integument reddish brown to blackish brown; elytra brown to reddish­brown.

Head. Width 3.6–4.2 as long as distance between upper lobes of eyes; postclypeus without a transverse shining carina in front of transverse groove between tentorial pits; distance between lower lobes of eyes 1.6–2.1 as long as distance between antennal socket and lateral angle of postclypeus, and 1.5–1.7 as long as distance between upper lobes of eyes. Antennae slightly longer than body; antennal scape, segment 4 longer or as long as segment 3, and segment 5 as long as segment 6.

FIGURES 31–38. Oemona hirta: 31, median lobe and internal sac: sr, spined region; ur, unspined region; S 1 –S 3, spined sections 1–3; 32, male eighth sternite; 33, male eighth tergite; 34, tegmen; 35, ventral apodeme; 36, ovipositor; 37, spermatheca; 38, female eighth sternite. sm, simple microspines. Scale lines for Figs 31 –36, 38 = 1 mm; scale lines for Fig. 37 = 0.4 mm.

Thorax. Prothorax sub­cylindrical, 1.1–1.2 as long as wide; disc with distinct, long, transverse rugae and pale yellow hairs; each side with dense, fine punctures and pubescence. Prosternum in front of coxae divided by a transverse depression into two parts, with anterior smooth and shining, and posterior with some transverse obsolete wrinkles or a few shallow punctures. Elytra 2.9–3.2 as long as shoulders, and 3.7–4.2 as long as prothorax; surface with pale yellow hairs and coarse and rugose punctures, with punctures becoming shallower and confused towards apex. Hind femora 1.9–2.3 as long as prothoracic width.

Terminalia. Apex of ventral and dorsal median lobes pointed with dorsal lobe more robust; ventral lobe longer than dorsal lobe. Spined region of internal sac about 2 as long as basal unspined region, divided into 3 sections: first section about 0.5 as long as basal unspined region, with simple spines; second section about 3 as long as first section, with hair­shaped spines, cloud­like processes and scale­like and net­like areas; third section about as long as first section, without spines (Fig. 31). Eighth sternite rounded at sides, apex slightly emarginate, with dense setae but no setae in middle area; ventral surface with dense simple microspines; a V­shaped membranous area in middle area; width <3 as long as length (middle), and <2 length of needle (Fig. 32). Apex of eighth tergite distinctly emarginate, with dense simple microspines on dorsal surface (Fig. 33). Parameres about 1 / 7 length of tegmen (Fig. 34). Ventral apodeme with an inner process between arms but no setae on process, stem longer than arms (Fig. 35).

Female (Fig. 30). Body length: 14.3–30.9 mm.

Antennae as long as or slightly longer than body; width of head 3.0– 3.3 as long as distance between upper lobes of eyes; prothorax without punctures at sides; elytra 2.9–3.2 as long as shoulders and 3.8–4.1 as long as prothorax.

Ovipositor. Paraproct bacculi extending from about basal 1 / 4 to apical 1 / 6; proctiger baculi 0.8 length of paraproct baculi and 1.9 length of dorsal baculi. Length of atylus longer than width of coxite (Fig. 36).

Spermatheca. Slightly curved, moderately narrowed towards base. Spermathecal gland arising from basal 1 / 3 of spermatheca (Fig. 37).

Eighth sternite. Spade­shaped, width slightly longer than length (Fig. 38).

Biology

Oemona hirta is one the most common insects in New Zealand and is an important pest of citrus, apple and grapes. It attacks a very wide range of introduced and native plants. According to Spiller and Wise (1982) and Kuschel (1990), more than 40 genera of plants are recorded as host plants of O. hirta: Acacia pycnantha, Acer sp., Albizia julibrissin, Aleurites fordii, Aristorelia serrata, Azara sp., Betula sp., Brachyglottis repanda, Cassinia leptohylla, C. retorta, Casuarina sp., Chamaecyparis sp., Citrus spp., C. limon, Coriaria sp., Cupressus sp., Cyphomandra betacea, Cytisus proliferus, Dahlia excelsa, Fraxinus sp., Freycinetia sp., Gahnia sp., Hakea salicifolia, Hedycarya sp., Hoheria sp., Idesia sp., Juglans regia, Leptospermum sp., L. scoparium, Ligustrum sp., Macropiper sp., Malus sylvestris, Melicytus sp., Muehlenbeckia sp., Olearia solandra, O. traversii, Parsonsia sp., Pittosporum sp., Populus migra cv. italica, Prunus amygdalus, P. armeniaca, P. avium, P. domestica, P. perscai, P. perscia var. nectarina, Punica sp., Pyrus communis, Quercus sp., Ribes uva­crispa, Ripogonum sp., Rosa sp., Salix caprea, Schefflera sp., Senecio renoldii, Solanum sp., Sophora sp., Tabebuia sp., Ulex europaeus, Ulmus sp., Virgilia sp., Vitex lucens and Vitis vinifera. In addition, the following are recorded as host plants of this species during the present study: Albizia lophantha, Avecinnia resinifera, Cryptomeria japonica, Macadamia tetraphylla, Nothotsgus truncata, and Solanum auriculatun.

The biology of O. hirta, particularly its life cycle, has been observed or reviewed by various authors (Dumbleton 1957, Cottier 1938, Duffy 1963, Hosking 1978, Clearwater 1981, Muggleston 1992). In most parts of New Zealand, this insect requires at least 2 years to complete its life cycle. Between September and January eggs are laid singly in fresh pruning wounds, leaf and branch junctions, and cracks in the bark. The larval stage takes> 1 yr and larvae can be found all year round. Newly hatched larvae bore directly into sapwood and then into hardwood. They make tunnels in branches with a series of frass ejection holes every few inches. Before pupation occurs, the larva tears off thin pieces of wood and packs them into 2 tight plugs 1.77 cm long and 2.5 cm apart, between which it then pupates. The pupal period is 3 wk. Pupae can be found between late May and early November. Adults emerge between early September and early February with a peak occurring between October and December. More recently, Wang et al. (1998, 2002) studied the reproductive biology and rearing methods of O. hirta in the laboratory. Adults emerged from field­collected pupae lay about 50 eggs in their lifespan. Adults are active during the scotophase, involving feeding, mating and oviposition. Mean larval development time ranges from ~ 150 to almost 300 d, depending on rearing methods. Mean pupal stage ranged from 15 to 19 d.

Two ichneumonid species [Xanthocryptus novozealandicus (Dalla Torre) and Campoplex sp.] and one braconid species (Apsicolpus hudsoni Turner) are recorded attacking larvae of this beetle (Wang & Shi 1999, 2001).

Distribution (Fig. 49)

This beetle occurs throughout New Zealand.

Comments

The species may be distinctly discriminated from other Oemona species by the pronotal disc with distinct transverse rugae; tarsal segments 2–5, apical areas of scape, femora and tibiae blackish brown.

This is the most variable species in the genus Oemona. In many specimens, tarsal segment 1 may be blackish brown, and the basal ½ of the femora pale red. In some specimens the transverse rugae on the pronotal disc may become vague.