Tinocallis takachihoensis (Japanese elm aphid): identification, images, ecology, control

All adult Tinocallis takachihoensis viviparae are winged. These alates (see first picture below) are pale yellow-green with a shiny black head and thorax (cf. Tinocallis platani, which has head and prothorax yellow with brown longitudinal stripes). The pattern of black markings on the wings is diagnostic. The antennae are about 0.88 times as long as the body, and segment III bears 19-24 (mostly 22) secondary rhinaria. The terminal process is 0.92-1.2 times as long as base of antennal segment VI. The head bears no dorsal processes (cf. Tinocallis ulmiparvifoliae, which has three pairs of dorsal processes on the head). The pronotum and mesonotum each bear a pair of dorsal processes. The pair on the pronotum are small and pale, whilst the pair on the mesonotum are large and dark. There are also two pairs of paired dorsal processes on the abdominal dorsum. There are no brown markings on the abdominal dorsum (cf. Tinocallis platani, which has extensive dark dorsal makings on the abdomen). There is a black patch where the hind femur meets the hind tibia. The body length of Tinocallis takachihoensis alates is 1.8-2.0 mm.

Tinocallis takachihoensis (Japanese elm aphid) alate on Ulmus (elm) at Ringmer, East Sussex, UK on 30/7/14 at 09.26 h.

Immature Tinocallis takachihoensis are pale yellow green with numerous tubercles topped with capitate hairs. They form large colonies with the alates on the undersides of the leaves (see second picture above). The micrographs below show (first) an alate in posterior-lateral view and (second) a dorsal close-up of the head and thorax showing the two pairs of dorsal processes.

Micrograph of Tinocallis takachihoensis (Japanese elm aphid) showing wing pattern

The Japanese elm aphid feeds on elm (Ulmus species) and some other genera in Japan, China and eastern Siberia. Tinocallis takachihoensis has also been introduced to Europe (France, Germany, England, Netherlands, Sicily, Andorra) and the USA. It now appears be established in most of these countries.

Biology & Ecology:

Introduction to Britain

In Britain Tinocallis takachihoensis has been regularly found on imported Bonsai plants (Ulmus and Zelkova spp.) (Roques & Auger-Rozenberg, 2006). It was first recorded in England in 'the wild' by Döring (2007, 2008) who collected it on whych elm (Ulmus glabra) in Berkshire. Tinocallis takachihoensis has also been recorded in 2012 from Lincoln, UK by Mick Talbot.

Tinocallis takachihoensis (Japanese elm aphid) alate on Ulmus glabra (wych elm) at Shoreham-by-Sea houseboats, West Sussex on 13/10/16 at 17.46 h.

We first confirmed the presence of Tinocallis takachihoensis in East Sussex in July 2010 on elm trees at Friston Forest, although immatures we found there in 2007 were also probably of this species.

Tinocallis takachihoensis (Japanese elm aphid) alates and alatiform nymphs on Ulmus (elm) at Stanmer, East Sussex, UK on 2/7/14 at 18.53 h.

Since 2014 we have found them in large numbers on elm in several locations in East Sussex (Middle Farm, Alfriston, West Dean, Ringmer) and West Sussex (Stanmer).

Life cycle

When we first found Tinocallis takachihoensis in Britain, in 2010, it was unclear how the species was overwintering. Was it producing sexuales and overwintering as eggs? Or was it continuing to reproduce parthenogenetically regardless of the colder weather? Then in October 2018 we found immature and mature oviparae on elm at Alfriston in East Sussex, England, thus confirming that at least some of the population overwinters in the egg stage. The pictures below show (first) an immature ovipara and (second) a mature ovipara. It is yellow with orange hues and has strongly swollen tibiae.

Tinocallis takachihoensis (Japanese elm aphid) immature ovipara on Ulmus (elm) at Alfriston, East Sussex

Some of the oviparae were instead bright orange from the mesonotum to around tergites VI-VII (see picture below).

Tinocallis takachihoensis (Japanese elm aphid) orange ovipara on Ulmus (elm) at Alfriston, East Sussex on 28/10/18 at 11.06 h.

Patti & Barbagallo (1998) report alate males and oviparae in Sicily from mid-October. Piron (2013) suggested that with climate change in Western Europe the climate may be similar enough to Japan to enable Tinocallis takachihoensis to survive milder winters parthenogenetically, even with occasional severe frosts.

Natural enemies

There are few observations on the natural enemies of Tinocallis species. Lumbierres et al. (2005) have recorded the coccinellid Oenopia conglobata (see picture below) as a predator of Tinocallis takachihoensis in Lieida, in the Iberian Peninsula.

Oenopia conglobata at Namur, Belgium on April 19, 2010. Image by Gilles San Martin.

Image by Gilles San Martin from Namur, Belgium (Oenopia conglobata)
Uploaded by Jacopo Werther) [CC BY-SA 2.0], via Wikimedia Commons.

Other aphids on same host:

Tinocallis takachihoensis has been recorded from 4 Ulmus species (Ulmus canescens, Ulmus glabra, Ulmus ×hollandica, Ulmus japonica).

Blackman & Eastop list about 75 species of aphids as feeding on elms worldwide, and provides formal identification keys for aphids on Ulmus.

Blackman & Eastop list 22 species that feed on English elm (Ulmus procera) worldwide (Show World list). Of those aphid species, Baker (2015) lists 14 as occurring in Britain: (Show British list).
Blackman & Eastop list 22 species that feed on wych elm (Ulmus glabra) worldwide (Show World list). Of those aphid species, Baker (2015) lists 15 as occurring in Britain (Show British list).

Acknowledgements

Special thanks to Roger Blackman for correcting our original erroneous description of the dorsal processes.
Whilst we make every effort to ensure that identifications are correct, we cannot absolutely warranty their accuracy. We have mostly made identifications from high resolution photos of living specimens, along with host plant identity. In the great majority of cases, identifications have been confirmed by microscopic examination of preserved specimens. We have used the keys and species accounts of Higuchi (1972), Richards (1967), and Quednau (2001) along with information from Roger Blackman & Victor Eastop in Aphids on Worlds Plants. We fully acknowledge these authors and those listed in the reference sections as the source for the (summarized) taxonomic information we have presented. Any errors in identification or information are ours alone, and we would be very grateful for any corrections. For assistance on the terms used for aphid morphology we suggest the figure provided by Blackman & Eastop (2006).

Useful weblinks

References

Döring, T.F. (2007). Colonies of the Asian elm aphid Tinocallis takachihoensis Higuchi (Hemiptera: Aphididae) in Britain. The Entomologist's record and Journal of Variation 119(5), 226-227. Full text
Döring, T.F. (2008). Further sightings of the Asian elm aphid Tinocallis takachihoensis Higuchi (Hemiptera: Aphididae) in Britain. The Entomologist's record and Journal of Variation 120, 32.
Higuchi, H. (1972). A taxonomic study of the subfamily Callipterinae in Japan (Homoptera : Aphididae). Insecta Matsumurana 35, 19-126. Full text
Lumbierres, B. et al. (2005). Parasites and predators of aphids associated with public green areas of Lieida (NE Iberian Peninsula). Adv. Hort. Sci. 19(2), 69-75. Full text
Patti, I. & Barbagallo, S. (1998). Aphids of genus Tinocallis infesting elms in Italy (Homoptera, Aphididae). Informatore Fitopatologico 48(12), 21-30. Abstract
Piron, P.G.M. (2013). Appearance of Tinocallis takachihoensis (Homoptera: Aphididae) in The Netherlands. Entomologische Berichten 73(6), 251-252. Full text
Roques, A. & Auger-Rozenberg, M.-A. (2006). Tentative analysis of the interceptions of non-indigenous organisms in Europe during 1995-2004. Bulletin OEPP 36, 490-496. Full text

Tinocallis takachihoensis

Japanese elm aphid

Identification & Distribution