INTERESTING INSECTS

By N A Martin (2017)

Lily aphid, Crescent-marked lily aphid, Mottled arum aphid

Siphonophora circumflexa Buckton, 1876

Nectarophora circumflexa (Buckton, 1876)

Myzus circumflexus (Buckton, 1876)

Myzodes circumflexus (Buckton, 1876)

Aulacorthum circumflexus (Buckton, 1876)

Aulacorthum (Neomyzus) circumflexus (Buckton, 1876)

Macrosiphum circumflexum (Buckton, 1876)

Myzus circumflexum (Buckton, 1876)

Neomyzus circumflexum (Buckton, 1876)

Macrosiphum pelargonii van der Goot, 1915

Macrosiphum primulanum Matsumura, 1917

Myzus vincae Gillette, 1908

Siphonophora callae Henrich, 1909

Neomyzus callae (Henrich, 1909)

This adventive aphid is found in many countries. It is believed to originate in East Asia. In New Zealand, like in other countries, it may live on a wide variety of plants from many families. It is very polyphagous. It is found on native plants as well on naturalised and cultivated plants. In cooler areas it may be found in greenhouses.

Conservation status: It lives on native plants in native ecosystems, and on naturalised and cultivated plants. It may be a minor pest.

Only females of the Lily aphid are known. Adults may be winged or wingless and give live birth to nymphs. Wingless adults are shining nearly white or pale yellow to bright green. They have distinctive dark markings on the upper, dorsal, side of the body. The dark markings consist of transverse bands or paired patches on the thorax (middle part of the body) and a large roughly U-shaped, patch on the abdomen. The winged female also has black markings on its dorsal surface and on the underside of the thorax. Like other aphids it has two pairs of wings. The adults and nymphs have three pairs of legs and one pair of antennae. Legs and antennae tend to have dark areas, especially at the joints. On the underside of the head is the rostrum, that holds the stylets used for feeding. When not in use the rostrum points back between the legs. Towards the rear of the abdomen is a pair of tubes, siphunculae, from which honeydew is secreted. The siphunculae and the cauda (central projection at rear of abdomen) are the same colour as the body.

Adult females give live birth to nymphs that look like small wingless adults. The first instar (stage) nymph has pale legs and siphuncles, and the end of the abdomen is rounded. There are four nymphal stages. Nymphs go from one stage to the next by moulting, changing their skin. The mature nymph moults into the adult. Nymphs that are going to develop into winged adults have wing buds.

Feeding and honeydew

Like other Hemiptera, the Lily aphid has sucking mouthparts. The two pairs of long stylets (specially shaped rods) are held in the rostrum. When it wishes to feed, the aphid moves the tip of the rostrum to the surface of the plant. The stylets are then gradually pushed into the plant. One pair of stylets, the maxillae, form two tubes; one through which saliva is injected into the plant and a second through which plants juices are sucked up into the insect. The Lily aphid inserts the stylets into the phloem (the plant vessels for transmitting sap from the leaves to other parts of the plant). The sap has a high volume of water and sugars, more than the insect needs. Excess water and sugar is excreted from the siphuncles and called honeydew.

Side view of a winged Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae): note the rostrum on the underside of the head and pointing backwards. Creator: Tim Holmes. © Plant & Food Research. [Image: 2MU3]

Dorsal (top) side of a winged Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MTZ]

Underside of a winged Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MTX]

Wingless adult female Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae): note the moulted nymphal skin. Creator: Tim Holmes. © Plant & Food Research. [Image: 2MU8]

Wingless adult females and nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae). Creator: Nicholas A. Martin. © Nicholas A. Martin. [Image: 2MUN]

Wingless adult females and nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae). Creator: Nicholas A. Martin. © Nicholas A. Martin. [Image: 2MUM]

Nymphs and wingless adult females of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUE]

Nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on leaf stalk of Kawakawa, Piper excelsum (Piperaceae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MU9]

Wingless female and nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on frond of Single crepe fern, Leptopteris hymenophylloides (Osmundaceae): note the wing buds on the two nymphs. Creator: Tim Holmes. © Plant & Food Research. [Image: 1HYU]

Wingless female of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on frond of Single crepe fern, Leptopteris hymenophylloides (Osmundaceae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MTV]

Nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on frond of Single crepe fern, Leptopteris hymenophylloides (Osmundaceae): note the wing buds on the nymphs. Creator: Tim Holmes. © Plant & Food Research. [Image: 2MU7]

Normally aphids require specialist skills for their identification, However, wingless female Lily aphids typically are shining nearly white or pale yellow to bright green, with distinctive sclerotic dorsal markings, consisting of transverse bands or paired patches on the thorax and a large roughly U-shaped, patch on the abdomen. The distinctive dark pattern on the dorsal (upper) side of the abdomen makes them easily recognisable. Some populations have wingless females that lack the dark markings on their abdomens and non-experts cannot reliably identify them.

On ferns, Lily aphids without dark marking on their abdomen can be distinguished from Green fern aphids, Micromyzella filicis (van der Goot, 1917) (Hemiptera: Aphididae) which has black cornicles and cauda.

Drawing of the abdomen of a wingless female Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae). Creator: W. Cottier. © Image from figure 60 drawn by W. Cottier in 1953 in Aphids of New Zealand published by the N.Z. Department of Scientific and Industrial Research Bulletin volume 106. [Image: 2MUL]

Wingless adult female Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUF]

Wingless adult female Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae): note the moulted nymphal skin. Creator: Tim Holmes. © Plant & Food Research. [Image: 2MU8]

Nymphs and wingless adult females of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUE]

Dorsal (top) side of a winged Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MTZ]

Winged adult Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUG]

Underside of a winged Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MTY]

Wingless female Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on frond of Single crepe fern, Leptopteris hymenophylloides (Osmundaceae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MU6]

Wingless female green fern aphid Micromyzella filicis (van der Goot, 1917) (Hemiptera: Aphididae); the arrows point to one of the two siphuncles and the cauda. Creator: Tim Holmes. © Plant & Food Research. [Image: 2FKC]

Two parasitoid wasps have been reared from Lily aphids. There may be other parasitoids and the aphids are probably preyed upon by birds, spiders and predatory insects.

Mummified Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on frond of Single crepe fern, Leptopteris hymenophylloides (Osmundaceae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MU4]

Mummified Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on frond of Single crepe fern, Leptopteris hymenophylloides (Osmundaceae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MU5]

Mumified Lily aphids, Neomyzus circumflexus (Hemiptera: Aphididae) on the underside of a leaf of Kawakawa, Piper excelsum (Piperaceae): note the two kinds of mummies. Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUA]

Two kinds of adult parasitoid waps (Hymenoptera) reared from mummified Lily aphids, Neomyzus circumflexus (Hemiptera: Aphididae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUD]

Underside of two kinds of adult parasitoid waps (Hymenoptera) reared from mummified Lily aphids, Neomyzus circumflexus (Hemiptera: Aphididae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUB]

Side view of two kinds of adult parasitoid waps (Hymenoptera) reared from mummified Lily aphids, Neomyzus circumflexus (Hemiptera: Aphididae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUC]

Lily aphids feed on a wide range of plants, ferns, herbaceous plants, climbers shrubs and trees belonging to many families. It is very polyphagous. Aphid colonies are mainly found on young leaves, shoots and inflorescences.

Feeding and honeydew

Like other Hemiptera, Lily aphids have sucking mouth parts. The long stylets, special shaped rods, are held in the rostrum. When it wishes to feed the aphid moves the tip of the rostrum to the surface of a leaf or stem. The stylets are then gradually pushed into the plant. The inner pair of stylets, form two tubes, one through which saliva is injected into the plant and a second through which plants juices are sucked up into the insect. Lily aphids insert its stylets into the phloem, the plant vessels for transmitting sap from the leaves to other parts of the plant. The sap has a high volume of water and sugars, more than the insect needs. Aphids excrete the excess water and sugar, which is called honeydew.

Wingless adult females and nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae). Creator: Nicholas A. Martin. © Nicholas A. Martin. [Image: 2MUN]

Wingless adult females and nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of Kawakawa, Piper excelsum (Piperaceae). Creator: Nicholas A. Martin. © Nicholas A. Martin. [Image: 2MUM]

Nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on frond of Single crepe fern, Leptopteris hymenophylloides (Osmundaceae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MTU]

Wingless female and nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on frond of Single crepe fern, Leptopteris hymenophylloides (Osmundaceae): note the wing buds on the two nymphs. Creator: Tim Holmes. © Plant & Food Research. [Image: 1HYU]

Winged female of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on frond of Single crepe fern, Leptopteris hymenophylloides (Osmundaceae). Creator: Tim Holmes. © Plant & Food Research. [Image: 2MU0]

Wingless adult females and nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of New Zealand jasmine, Parsonsia heterophylla (Apocynaceae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUJ]

Wingless adult females and nymphs of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on underside of leaf of New Zealand jasmine, Parsonsia heterophylla (Apocynaceae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUI]

Wingless adult female of Lily aphid, Neomyzus circumflexus (Hemiptera: Aphididae) on inflorescence of Renga lily, Arthropodium cirratum (Asparagaceae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2MUK]

The Lily aphid may occasionally cause concern in a garden or on crops. If an insecticide is felt necessary, chose one that will cause least harm to predators and parasitoids.

Aphids on New Zealand ferns

In New Zealand five species of aphids have been found breeding on ferns. Two species are only found on ferns, while three species are polyphagous. The two specialist fern feeders are the black fern aphid, Idiopterus nephrelepidis Davis, 1909 and the green fern aphid, Micromyzella filicis (van der Goot, 1917). The latter is common in Auckland. The three polyphagous species are, Brachycaudus helichrysi (Kaltenbach, 1843), Myzus ornatus Laing, 1932, and the Lily aphid, Neomyzus circumflexus (Buckton, 1876).

Aphids on worlds plants; Neomyzus circumflexus. www.aphidsonworldsplants.info/d_APHIDS_N.htm#Neomyzus.

Cottier W. 1953. Aphids of New Zealand. N.Z. Department of Scientific and Industrial Research Bulletin. 106: 1-382.

Plant-SyNZ: Invertebrate herbivore-host plant association database. plant-synz.landcareresearch.co.nz/.

Dr Robert Foottit, Canadian National Collection of Insects, Ottawa, Canada, for identification of aphids.

The New Zealand Institute for Plant & Food Research Limited (Plant & Food Research) for permission to use photographs.