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Black-tailed bamboo aphidOn this page: Identification & Distribution Morphology Colour variant or another species? Biology & Ecology Life Cycle Other aphids on the same host
Identification & Distribution
All adult viviparae of Takecallis arundicolens are alate. Their immatures (see first picture below) may be pale or dark yellow in colour, and have long capitate hairs and a pale cauda. The adult alate Takecallis arundicolens is pale yellow or greyish yellow, usually without any dark dorsal abdominal markings (see second picture below) - but note, in the spring form, there may be a double row of dark spots around the spinal setae. There is a sparse covering of bluish white wax, especially over the antennae and the anterior of the aphid. The antennae are longer than the body. Antennal segment III of the alate has a pale base, adjacent to a dark portion which bears 5-7 rhinaria; the remainder of the antennal flagellum is usually variegated (but see colour variant in morphology section below). The cauda (clearly visible at the rear of the aphid's abdomen) is usually conspicuously black (but again see colour variant below). The body length of the adult alate is 1.8-2.8 mm.
The black-tailed bamboo aphid feeds on bamboo (Arundinaria, Bambusa, Phyllostachys and Sasa spp.) as well as (rarely) common reed (Phragmites australis). Takecallis arundicolens is an invasive species originally found in China, Taiwan, Japan, and Korea, but now also present in Europe and North America.
A colour variant - or a different species?
In July 2020 we had a report of some unusual Takecallis specimens (see picture below) on bamboo from Alan Orange in Wales.
Unlike the two common Takecallis species species found in Europe, the Welsh alatae had neither dark markings on the abdominal dorsum (characteristic of Takecallis arundinariae) nor the black cauda and variegated antennae (characteristic of Takecallis arundicolens). Using the key by Qiao & Zhang (2004), Alan suggested the Welsh Takecallis might be Takecallis takahashii, albeit the species is not mentioned by most recent literature on this genus. Diagnostic characters for Takecallis takahashii include the siphunculi having a hair at the base (see picture below), a pale or dusky cauda, and no stripes on the thoracic dorsum - all of which was true for the Welsh aphids.
Image above copyright Alan Orange, all rights reserved.
However, Takecallis takahashii is no longer accepted as a "good species" following the treatise of Quednau (2003) who synonomized it with Takecallis arundinariae. We detail below the characteristics of the aphids from Wales which eventually led us to conclude that this was instead an unusual variety (clone?) of Takecallis arundicolens. We used the keys and descriptions of Quednau (2003), Lee & Lee (2018) and Blackman & Eastop (2020), with supplementary information from Qiao & Zhang (2004). Comparisons are made with other species of the Takecallis genus for each character.
Images above copyright Alan Orange, all rights reserved.
The characters above all point to these Welsh aphids being Takecallis arundicolens, albeit two characters are atypical of this species:
We conclude that the Welsh population is a variant clone of Takecallis arundicolens.
Investigating the status of the name Takecallis takahashii proved problematical. The 'species' was originally described and named by Hsu (1980), and then redescribed by Tao (1990), neither of which publications are accessible. Takecallis takahashii was subsequently synonomized with Takecallis arundinariae by Quednau (2003). One might expect that it would have been synonomized with Takecallis arundicolens given that the specimens from Wales turned out to be this species. But the Qiao & Zhang (2004) key only uses the character "double row of elongate, dark spinal sclerites on the abdomen" late in their key, after Takecallis takahashii has already been identified on the basis of other characters - all of which the Welsh specimens possessed. Presumably Hsu's Takecallis takahashii specimens did have the characteristic double row of elongate, dark spinal sclerites on the abdomen, albeit lacking the dark thoracic stripes.
Biology & Ecology
Takecallis arundicolens is generally considered to be anholocyclic throughout its range, although Leclant (1966) (in Blackman & Eastop (1984)) reported oviparae in southern France. We have not found any evidence of sexual reproduction in southern England, but we have found adult parthenogenetic alatae reproducing throughout winter in local woodland (see picture below of an alate with offspring in January in southern England).
The black cauda is not very clear in the alate above, but is much more so in the image below.
By June large numbers of aphids can be found on the bamboo leaves.
Qiao & Zhang (2004) reviewed the Takecallis species occurring in China, including Takecallis arundicolens. Host plants recorded for the latter species include Phyllostachys species, Sasa nipponica, Sasa palmate and Sasa senaanensis.
There are very few reports of natural enemies of Takecallis arundicolens in the literature. Rakhshani et al. (2017) has reported a new parasitoid species, Trioxys remaudierei, attacking Takecallis aphids outside their area of origin.
Other aphids on same host: