The Aphids

SYSTEMATIC TREATMENT OF APHID GENERA

(in alphabetical order)

Aphidinae: Macrosiphini

About six species with elongate swollen siphunculi, cauda with only 5 hairs and apterae often without rhinaria on ANT III. One species utilizes Arbutus as secondary hosts.They are mostly of boreal distribution and associated with Rosa and/or Ericaceae, their biology thus being like that of Ericaphis which are probably their closest relatives. Accounts are available for western Europe (Hille Ris Lambers 1949, Heie, 1995) and UK (Stroyan 1979a, Blackman 2010).

Wahlgreniella empetri Richards Apterae are dull green with dusky appendages; BL 1.5-1.8 mm. Alatae have dark brown to black head, antennae and thorax. On Empetrum nigrum in northern Canada (Baffin Island).

Wahlgreniella lampeli Rupais Apterae are shining lemon-yellow; BL 2.1-2.6 mm. On Empetrum hermaphroditum in northern Russia (Murmansk).

Wahlgreniella nervata (Gillette) Plate 24d Apterae are spindle-shaped, pale yellow-green to dull mid-green, with dark-ringed antennae and dark tips to the long, slightly swollen siphunculi (see influentialpoints.com/Gallery); BL 1.4-2.5 mm. Alatae have a green abdomen with variably developed dark dorsal cross-bands, sometimes coalesced into an irregular patch. In western North America it is apparently host-alternating between Rosa and Ericaceae (Arbutus, Arctostaphylos, Pieris), although the host alternation still awaits proper experimental verification. Introduced populations on roses occur in Central and South America, Europe, Saudi Arabia (Hussain et al. 2015), Turkey, Iran (Rezwani 2001), Africa (Burundi), India (Joshi et al. 2014), Pakistan and Australia (first record 2017; Brumley 2020); these are anholocyclic in UK, and probably elsewhere. In Turkey it is recorded from Rosa ×damascena (Barjadze et al. 2011b). There has been an apparently separate introduction into Europe of another anholocyclic population, which is shining yellowish green in life and lives on Ericaceae (Arbutus, Arctostaphylos) and Empetraceae (Empetrum), and which we treat here as a subspecies, W. nervata ssp. arbuti (Davidson), following Hille Ris Lambers (1949). The two populations maintain their specific host associations and slight morphological differences in the field, although they can be reared on each other’s host plants in the laboratory. Remaudière & Remaudière (1997) list W. arbuti Davidson as a separate species. However, as the situation has apparently arisen as a result of separate, recent introductions to Europe from common North American stock, full species status may not be appropriate. [Wahlgreniella nervata has also been recorded in North America (Patch 1938) from Heteromeles (= Photinia) arbutifolia, but the host identification should perhaps be treated with suspicion.]

Wahlgreniella ossiannilssoni Hille Ris Lambers Apterae are shining pale yellow, dark green, reddish brown or greenish black, with siphunculi dark in middle and at tips; BL 1.5-2.3 mm. On undersides of leaves and shoots of Arctostaphylos uva-ursi. Boreo-alpine in distribution (northern Europe, Balkans, Alps and Pyrenees). The life cycle is variable; monoecious holocyclic (with alate males) on Arctostaphylos in northern Europe and at lower altitudes, but heteroecious holocyclic with a sexual phase on alpine Rosa spp. at altitudes above 1800m, migrating in the second generation to Arctostaphylos (Remaudière et al. 1978). Fundatrices and oviparae of monoecious and heteroecious populations show certain differences, and the genetic relationships between them are unclear. Anholocyclic overwintering on Arctostaphylos can also occur where conditions permit.

Wahlgreniella vaccinii (Theobald) (Fig.56e) Apterae are shining greenish yellow or yellowish green, and have antennae ringed with black; BL 1.6-2.3 mm. On the undersides of leaves of Vaccinium spp. in Europe and North America, where it is also recorded from Arctostaphylos uva-ursi. Monoecious holocyclic; yellow-orange oviparae and apterous males have been collected on Vaccinium in northern England and North Wales in late August-October (Blackman 2010). 2n=12.

Wahgreniella viburni (Takahashi) Apterae are green, with tips of siphunculi dusky; BL c.2 mm. Alatae have secondary rhinaria distributed III c.45, IV 8-10, V 0-3. It was described from alatae found in Taiwan collected on young leaves of Viburnum arboricola (= V. odoratissimum var. iwabuki), but apterae and alatae of apparently the same species were collected on Mahonia morrisonensis (= M. oiwakensis), so the true host is in doubt. An association with Mahonia would indicate that this species may belong in Liosomaphis, and is possibly synonymous with L. himalayensis.

Wanyucallis Quednau

Calaphidinae: Myzocallidini

One species in China with many characters of Hoplochaitophorus but with bulging spiculose spinal sclerites bearing stout hairs with blunt or slightly swollen apices, and other differences indicated in the key. See also Quednau (1999).

Wanyucallis amblyopappos (Zhang & Zhang) Only apterae are known, collected on Quercus liaotungensis in Beijing, China; BL c. 2 mm (W. Zhang & G. Zhang 1994, as Myzocallis).

Watabura Matsumura (? = Prociphilus Koch)

Eriosomatinae: Pemphigini

A genus for one species in east Asia which probably alternates between Maloideae and Pinus roots, although so far only known from the alate sexupara. It may be a small species of Prociphilus.

Watabura nishiyae Matsumura This species was described from alate ?sexuparae collected on Cydonia in Japan (Matsumura 1917). Sexuparae that appear to be the same species have subsequently been collected from roots of Pinus spp. (densiflora, thunbergii) in Japan (BMNH collection, leg D. Hille Ris Lambers), and from twigs and branches of a cultivated Malus sp. in Korea (BMNH collection, leg. V. F. Eastop). The sexuparae are small (BL 1.3-1.9 mm), wax-dusted in life (V.F. Eastop, unpublished observation), with secondary rhinaria distributed III 11-16, IV 4-10, V 5-10, VI 3-9. The spring generations on Malus and the apterous exules on Pinus roots have not been described. This species was confused in the literature for many years with Aphidounguis mali, and records of Watabura nishiyae from Ulmacaeae and roots of Malus apply to that species.

Weibanaphis Zhang, Chen, Zhong & Li

Aphidinae: Aphidini

One species in China described as a “genus and species dubia”. After examining some immature (paratype) specimens we conclude that the genus is probably not clearly distinct from Aphis.

Weibanaphis alhagis Zhang, Chen, Zhong & Li Colour of apterae in life is unrecorded, presumably dark or with extensive dark dorsal markings; BL c.2..4 mm. On Alhagi sparsifolia in Xihiang, China (Zhang 1999).