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Takecallis taiwana (= Takecallis taiwanus)
Bamboo shoot aphidOn this page: Identification & Distribution Biology & Ecology: Life cycle Interspecific competition / association Natural enemies Other aphids on the same host Damage & Control
Identification & Distribution
All viviparous adult Takecallis taiwana are alate. The alatae are pale green without wax, with a longitudinal dusky stripe on the middle of the head (see first picture below). The antennae are as long as, or shorter than, the body (cf. Takecallis arundinariae & Takecallis arundicolens which have antennae longer than the body - note this discriminant is not reliable when looking at wet mounts), and are dark brown but with the basal part of segments III-VI pale. The thorax is light brownish-green, and the wings have slightly dusky bordered veins. There are no markings on the abdominal tergites, but abdominal tergites I and II bear conspicuous spinal tubercles (see second picture below). The siphunculi are pale and short with a dusky apex. Each siphunculus is situated in front of the marginal hair of abdominal tergite VI (cf. cf. Takecallis arundinariae & Takecallis arundicolens which both have the siphunculus bearing the marginal hair of abdominal tergite VI on its posterior face). The cauda is pale and knobbed. The adult body length of Takecallis taiwana is 1.4-2.3 mm.
Immature Takecallis taiwana (see second and third pictures above) are distinctive being yellow-green to green with rows of dark spines on the dorsum.
The bamboo shoot aphid feeds on bamboos, usually Arundinaria and Phyllostachys species, or sometimes Bambusa or Sasa. Colonies can be found in the young, still unrolled leaves and on the younger leaves. Larger, more mature, colonies live on the undersides of the leaf bases. Sexual forms have been recorded in China, but where introduced it is thought to be anholocyclic, reproducing parthenogenetically throughout the year. Takecallis taiwana is native to China, Taiwan and Japan but has been introduced to Europe, South Africa, New Zealand, USA and South America.
Biology & Ecology
Stroyan (1977) only recorded Takecallis taiwana from Surrey, and describes it as being very rare in Britain. We have also found it be rare, finding it for the first time in June 2019 on bamboo growing in a hotel garden in Alfriston, East Sussex. Colonies comprised of young nymphs were found in the still-rolled young shoots of bamboo. The alate (see picture below) deposits the nymphs at the edge of a leaf roll, and the nymphs then move into the comparitive safety of the rolled young shoot.
The picture below shows the first and second instars in the leaf roll - the first instars are yellowish, but older instars are green.
Immature Takecallis taiwana have four longitudinal rows of dark spines running along the dorsum from the head to abdominal segment VI. Immature Takecallis arundinariae and Takecallis arundicolens have similar rows of spines, but they are pale, not dark. Shoots with aphid colonies often have parts that are prematurely senesced, possibly the result of the aphids' feeding.
As colonies grow and leaves unroll, the aphids spread out from the shoots over the undersides of the leaf bases.
In Brazil, Lazzari et al. (1999) reports low catches of alates of Takecallis taiwana in yellow pan traps - one was caught in mid-June, and four from the end of October to the end of December.
Interspecific competition / association
There is considerable niche separation between Takecallis taiwana and the other two co-occurring Takecallis species, Takecallis arundinariae and Takecallis arundicolens. Takecallis taiwana favours young shoots, whereas the other two prefer mature leaves. Nevertheless Takecallis taiwana can sometimes be found feeding with at least one of the other species. The picture below shows an immature green Takecallis taiwana feeding with several pale yellow immatures of another Takecallis species.
In Italy Limonta et al. (2002) found that the two species showed temporal niche separation. Takecallis arundinariae developed from February to the end of May and Takecallis taiwanus from the beginning of May to the first days of August.
The only natural enemies we encountered on the bamboo in Alfriston, East Sussex were small spiders (see picture below) which lived on the bamboo leaves and did appear to be feeding on the aphids.
There are rather few reports of natural enemies of Takecallis arundicolens in the literature. In Georgia, Agekjan (1973) recorded three chrysopid and three hemerobiid species as predators of Takecallis taiwanus and another bamboo aphid, Melanaphis bambusae, in the region of the Black Sea coast. Rakhshani et al. (2017) reported a new parasitoid species, Trioxys remaudierei, attacking Takecallis aphids outside their area of origin.
Zhou et al. (2006) carried out bioassays and scanning electron microscopy of the entomophthoran fungus Conidiobolus obscurus for bamboo aphids as well as its effects on the fecundity of bamboo aphids to estimate bamboo aphid biocontrol potential. Conidiobolus obscurus can effectively infect four species of bamboo aphids, and most cadavers appeared in the first 2 days after inoculation. The final mortalities reached 74-91% at high concentrations of conidia among the tested species. The lowest LC 50 was estimated to be 57 conidia per mm2 for Takecallis taiwanus on day 5 after conidial shower. Moreover, the Conidiobolus obscurus-infected aphids only produced 3.9-18.2% progeny of the corresponding healthy aphids. It was concluded that Conidiobolus obscurus is able to restrain the development of bamboo aphid populations, and is suitable for further application in aphid biocontrol in bamboo forests.
Other aphids on the same host
Takecallis taiwana has been recorded from 8 Phyllostachys species, plus Arundinaria gigantea, Chimonobambusa quadrangularis, Yushania anceps, and one or more 'Unidentified Bambusa species'.
Blackman and Eastop list about 65 aphid species that feed on bamboo (Bambusa and other genera) worldwide (Show World list). Of those aphid species, Baker (2015) lists just 4 as occurring in Britain (Show British list).
Damage and control
Takecallis taiwana is often regarded as an important pest of bamboo, with control measures applied both within its native area in China, and in countries where it is invasive. Hu Guoliang et al. (2001). reported that in Zejiang the aphid damages the tender leaves and shoots of three species of Phyllostachys bamboo They report Takecallis taiwana goes through 50 parthenogenetic generations a year and does not have a sexual stage. They describe methods of control using various insecticides including cyhalothrin and malathion.