Aphis beringiensis, Stekolshchikov, Andrey V. & Khruleva, Olga A., 2015

Stekolshchikov, Andrey V. & Khruleva, Olga A., 2015, Contributions to the aphid fauna (Hemiptera, Aphidoidea) of Chukotka Autonomous Okrug with descriptions of five new species, Zootaxa 4044 (1), pp. 1-44 : 12-14

Aphis beringiensis sp. nov.

( Figs. 19–25 , Tabl. 2)

Type material. Holotype: alate viviparous female, No. 10263, slide No. 1, “ Aphis beringiensis sp. nov., Chukotka Autonomous Okrug, Anadyrskiy District, 40 km SSW vill. Beringovskiy, N 62° 43', E 178° 56', in yellow trap, 21.vii.2012, coll. A.V. Stekolshchikov”. Paratypes: 1 al., No. 10253, from the same locality as holotype, 18.vii.2012, in yellow trap; 2 al., No. 10263, together with holotype; 1 al., No. 10277, from the same locality as holotype, 20.vii.2012.

Etymology. The name beringiensis is derived from the geographical name “Beringia”, a loosely defined region which includes parts of Chukotka and Kamchatka in northeastern Asia as well as Alaska and Yukon in western North America.

Description. Alate viviparous female. Body egg-shaped, 2.0–2.3 (2.1) times as long as its width. Colour of living specimens unknown. Cleared specimens with head, thorax, 1st and 2nd antennal segments, sclerite at bases of coxae, coxae, trochanters, middle and hind femora (except for base), bases and apices of tibiae, tarsi, siphunculi and cauda dark brown; 2nd–6th antennal segments, bands, and marginal sclerites on abdomen, peritremes, subgenital and anal plates brown; fore femora and tibiae light brown. Abdomen with bands on tergites I–VIII, small marginal sclerites on I and VII, and large marginal sclerites on segments II–VI; marginal sclerites on segments V and VI partially fused and forming sclerotized area around siphunculi; marginal sclerites and bands on segments VI–VII always fused. Surface of head, dorsal and ventral side of thorax smooth or slightly wrinkled; surface of abdominal tergites I–V indistinctly reticulate, contour of reticulate cells formed by very flat large spinules; abdominal tergite VI with sparse rows of smooth spinules situated on the contour of reticulate cells; tergite VII with rows of smooth spinules which on tergite VIII partially fuse to form short scales; marginal sclerites on segments II–VI with sparse rows of large smooth spinules sometimes situated on the contour of reticulate cells; ventral side of abdomen with long rows of small pointed spinules forming strongly stretched reticulate cells. Thoracic, abdominal, and occipital and frontal setae on head finely pointed; on abdominal tergites I–IV two pairs of spinal setae: the pair situated nearer to the body margin relatively long (up to 30–51 Μm), the pair situated nearer to the central line of body very short (up to 10 Μm) with very small base, sometimes almost invisible; numbers of marginal setae 1, 2–3, 2, 2–3, 1–3, 2–3 and 1 on each side of abdominal segments I–VII, respectively. Marginal and spinal tubercles absent. Head without trace of epicranial coronal suture. Frontal tubercles distinct but not well developed; median tubercle projecting beyond antennal tubercles. Antennae 6-segmented, 1st and 2nd antennal segments slightly wrinkled, almost smooth, 3rd–6th segments with large scales. Third antennal segment with 4–9 (4.5–7.0) secondary rhinaria, 4th and 5th segment without rhinaria. Secondary rhinaria are round or oval, often large (with internal diameter 15–20 Μm), weakly protruberant, with external diameter 2.6–7.0 times as long as their height. Antennae with pointed or finely pointed setae. Rostrum reaching mesothorax. Ultimate rostral segment elongate wedge-shaped with straight or slightly concave sides, 2.29–2.45 (2.36) times as long as its basal width. Legs normal, setae on legs finely pointed or rarely simply pointed. Chaetotaxy of first tarsal segments 3, 3, 3 on three specimens, 3, 3, 2 on one specimen and one specimen with first tarsal segments on one hind leg with 2 and on other legs with 3 setae. Spiracles reniform. Siphunculi cylindrical, faintly narrowed at base, coarsely imbricate and with very small, almost unnoticeable flange. Subgenital plate oval, setae on subgenital and anal plate finely pointed. Cauda finger-shaped with a slight constriction at mid-length and long finely pointed setae.

Measurements of holotype. Body—1878×883, fore wing—2843, antenna—1032: III—286×30 (in the middle), IV—154, V—167, VI—106+175; hind femur—467, hind tibia—832; siphunculus—147×37 (in the middle); cauda—197×129 (at base) ×101 (before base). For more biometric data see Table 2.

Distribution. Known only from the type locality—Chukotka AO, Anadyrskiy District, 40 km SSW vill. Beringovskiy.

Biology. Unknown. All specimens were collected by yellow trap.

Systematic relationships. As in Aphis aquilonalis sp. nov., this species can be distinguished from any other known species of the genus Aphis by the lack of marginal tubercles on both abdominal segments I and VII.

Aphis beringiensis differs from A. aquilonalis sp. nov. by: the ratio of the processus terminalis to the base of last antennal segment; the ratio of the longest occipital and frontal seta to the articular diameter of the 3rd antennal segment; the numbers of setae on abdominal tergite VI between siphunculi, on tergite VIII, and on the anterior and posterior parts of the subgenital plate ( Tables 1 and 2). These characters distinguish not only alate viviparae of the two species (unfortunately, there is only one alate A. aquilonalis ), but also alate viviparae of A. beringiensis from apterous viviparae of A. aquilonalis .

Hille Ris Lambers (1955) described a new species Aphis atuberculata on the basis of two oviparous females and nymphs of males collected in Iceland with very small marginal tubercles which are present only on prothorax, abdominal segment I and more rarely also on segment VII. Perhaps this species is closely related to the species in Chukotka, but it still has the marginal tubercles on abdominal segment I. It also differs from both the new species by shorter siphunculi, small number of setae on cauda and 5-segmented antennae.

Figures

FIGURES 19 – 25. Aphis berengiensis sp. nov., al. 19, abdomen; 20, frons; 21, antenna; 22, ultimate rostral segments; 23, hind tarsus; 24, siphunculus; 25, cauda.