Aphis (Aphis) gaultheriae, Ciruelos, Sara I. Lopez, Brown, Paul A. & Nafria, Juan M. Nieto, 2018

Ciruelos, Sara I. Lopez, Brown, Paul A. & Nafria, Juan M. Nieto, 2018, Two new species of the genus Aphis (Hemiptera, Aphididae) from Chile on host species of Alstroemeriaceae and Ericaceae, ZooKeys 738, pp. 37-45 : 37

Aphis (Aphis) gaultheriae sp. n.

Types.

Holotype apterous viviparous female (measured specimen number 1), CHILE, Region X Los Lagos, province Chiloe, Lake Huillinco, on Gaultheria mucronata (L. fil.) E. J. Remy [ Pernettya mucronata on the label], 24 November 1974, Hille Ris Lambers leg. [928], mounted with two nymphs, Natural History Museum collection (BMNH(E) 1984-340). Paratypes: 2 apterous viviparous females collected with the holotype, mounted in two slides with nymphs, Natural History Museum collection (BMNH(E) 1984-340).

Apterous viviparous females.

(Figs 3, 4), from 3 specimens, all of them measured. Colour when alive unknown. When prepared, head, including clypeus, mandibular and maxillary lames brown; antennal segments I and II dark brown like segment VI; rostrum brown, coxae, trochanters, and most of femora dark brown (like antennal segment I), tibiae mainly very pale brown (like antennal segments III–V); dorsal thoracic and abdominal sclerites and genital plate brown (lighter than head), siphunculi, anal plate and cauda dark brown. Body 1.85-2.08 mm long, 1.88-2.24 times hind tibia (0.83-1.05 mm) and 5.49-6.27 times siphunculus. Antenna 1.25-1.56 mm and 0.68-0.79 times body length. Antennal segment III 0.35-0.43 mm and 1.32-1.42 times segment VI processus terminalis, dorsally almost smooth, and with 8-10 thick, pointed and very pale setae, 15-20 µm and 0.7-1.0 times subarticular diameter of antennal segment III [D], shorter than those on vertex (27-30 µm and 1.2-1.5 times D). Antennal segments IV and V respectively 0.18-0.25 and 0.20-0.26 mm. Segment VI processus terminalis 0.25-0.33 mm and 2.13-2.50 times segment VI base (0.12-0.14 mm). Rostrum slightly extending beyond the mid-coxae; ultimate rostral segment long (0.10-0.12 mm, 0.74-0.96 times base of antennal segment VI, 0.80-1.00 times second segment of hind tarsi), straight and with 2 very long and fine accessory setae. Dorsum of thorax with wide marginal sclerites and several pleural and spinal spots, paler than intersegmental sclerites and metathorax/first abdominal segment. Prothoracic marginal tubercles erect, protuberant and smaller than triommatidium. Inside setae on hind trochanter 37-40 µm and 0.67-0.73 times trochantrofemoral suture; dorsal setae on hind femora 25 µm and 1.1-1.3 times D. First segment of tarsi with 3 setae. Protuberant marginal tubercles on abdominal segments 1 and 7 delicate, but only those on segment 1 are especially delicate. Intermediate abdominal segments without marginal tubercles. Intersegmental sclerites darker than segmental and spiracular sclerites. Abdominal segments 1-4 with more or less abundant polygonal spinal sclerites that can be coalescent, and usually without marginal sclerites (polygonal cells are present in one specimen); abdominal segments 5 and 6 each with wide transverse spinopleural band, and abdominal segments 7 and 8 with individual narrow transverse stripes; this variability is similar to that presented by A. tehuelchis Nieto Nafria & Lopez Ciruelos, 2016 ( Lopez Ciruelos et al. 2016). Dorsal setae on thorax and abdomen also thick and pointed; marginal setae on intermediate abdominal segments 17-25 µm and 0.9-1.3 times D. Abdominal segment 8 with 2 setae, 20-22 µm and 0.9-1.1 times D. Siphunculi tapering on proximal 1/2-2/3 and distally cylindrical, with small flange and ornamentation of spinuled scales, 0.30-0.36 mm, 1.11-1.38 times cauda, and 6.00-6.56 times its diameter at mid length. Cauda robust finger-shaped, 0.26-0.27 mm and 1.93-2.30 times its basal width, with 10-11 long, delicate and curved setae.

Alate viviparous females and sexuales.

(Oviparous females and males). Unknown.

Host plant.

The type specimens of Aphis gaultheriae sp. n. were collected on Gaultheria mucronata (Ericaeae), which is known from Peru, Bolivia and southern Argentina and Chile (and introduced in Britain and Ireland).

Etymology.

The specific name " gaultheriae " is the plant host genus name of the aphid, in genitive.

Taxonomic discussion.

Species of 33 genera of Ericaceae have been reported as host plants of aphid species around the World, but only 16 host species of Aphis , many of which are polyphagous. Only seven Aphis species specializing on plant species belonging to Ericaceae are known: A. arbuti Ferrari, 1872, A. callunae Theobald, 1915, A. madronae Essig, 1926, A. multiflorae Barbagallo & Stroyan, 1982, A. remaudieri Borner, 1952, A. uvaeursi Ossiannilsson, 1959 and A. vaccini (Borner, 1914), which are European in distribution. Apterous viviparous females of Aphis gaultheriae sp. n. are recognizable by having spinal abdominal sclerotization, present at least on segments 5 to 8, extensively black femora, broad cauda more or less pigmented like siphunculi and similar to that of A. spiraecola , and an ultimate rostral segment no longer than the second segment of the hind tarsi.