Aphis urticae, Linnaeus, 1758

Williams, D. J. & Z. - Q, 2007, Carl Linnaeus and his scale insects (Hemiptera: Coccoidea) *, Zootaxa 1668 (1), pp. 427-490 : 461-463

Aphis urticae (Family Ortheziidae ) [now known as Orthezia urticae (L.)]

( Figures 1D, 12 )

Description

Adult female in life, covered in white waxy plates, mostly marginal and dorsal but distinctly divided on midline. Mature females secreting a long, ridged, white ovisac which is attached even when insect is mobile.

Slide-mounted specimens of adult female broadly oval. Antennae each with 8 segments, gently tapering, each segment with short, spine-like setae, terminal segment with longer apical seta. Eye stalks situated next to basal antennal segments but detached. Legs well developed, heavily sclerotized, trochanter and femur fused, trochanter with 3 campaniform sensilla on each side; tibia and tarsus divided but not articulating. Claw with short spinose digitules and 1–3 denticles. Anal ring with 2 bands of pores and with 6 setae, each longer than length of ring. Abdominal spiracles present, numbering 8 pairs.

Dorsal surface with submedial to medial and marginal to submarginal clusters of blunt spines, clusters separated by clear areas. A few pointed setae present, either within clusters of spines or in clear areas. Quadrilocular pores present in clear areas, almost surrounding dorsal clusters of spines.

Ventral surface with fairly wide ovisac band of spines. Other bands of spines present on head, across thoracic segments, surrounding thoracic spiracles and coxae to lateral margins and in 3 wide bands and 2 smaller bands within ovisac band. Quadrilocular pores present, surrounding bands of spines, numerous on inner margin of ovisac band, absent next to thoracic spiracles.

Comments

This species is represented in Linnaeus’ collection by a single pinned specimen labelled “urticae” in Linnaeus’ handwriting ( Figure 1D). There is no indication of how many specimens Linnaeus had at the time and this specimen is here designated lectotype (LSL). The specimen has the number 8 attached to it and this was listed by Jackson (1913a) in error under Chermes , mistaking it for Chermes urticae L., a psyllid now known as Trioza urticae (L.). Linnaeus (1758) gave a good description of this scale insect in his genus Aphis instead of Coccus and never altered this placement in his twelfth edition ( Linnaeus, 1767), although he had doubts whether the species belonged to Aphis or Chermes . The species was not listed in Fauna Svecica ( Linnaeus, 1761). Linnaeus supplemented his description with a reference to Frisch. ins. 8 (q.v.) showing an insect unmistakably Orthezia urticae (L.) as we know it today.

There are many synonyms to this species including Dorthesia characias Bosc d’Antic , and a specimen of this has been added to Linnaeus’ collection labelled Coccus characias Dorthes 1786 ( Figure 1A) but not in Linnaeus’ handwriting.

Orthezia urticae is fairly common throughout the Palaearctic Region on many host plants. It is one of the few scale insects that can survive after being submerged at high tide ( Harrison, 1916). For complete synonymy, distribution and host plant range see Miller et al. (2005). There are good descriptions of this species in Morrison (1925) and Kozár (2004). The illustration presented here is taken from Kozár (2004) with kind permission from the author and the Plant Protection Institute, Hungarian Academy of Sciences.

Figures

FIGURE 12. Aphis urticae L. Adult female. (Now Orthezia urticae (L.)).