Aphis epilobiphaga, Stekolshchikov, 2024

Stekolshchikov, Andrey V., 2024, A contribution to the aphid fauna (Homoptera, Aphidinea) of the Republic of Dagestan (the Russian Federation), with descriptions of three new species, redescription of Macrosiphum pulcherimum Nevsky, 1928, and descriptions of previously unknown morphs of three species, Zootaxa 5545 (1), pp. 1-68 : 26-30

Aphis epilobiphaga sp. nov.

( Figs 40–67 , Tables 4–5)

Type material. Holotype: apterous viviparous female, No. 11798, slide No. 14, “ Aphis epilobiphaga sp. nov., 2.ix.2023, Republic of Dagestan, Tlyaratinsky District, Federal State Nature Sanctuary “Tlyaratinsky”, nearby Salda Vill., Epilobium colchicum Albov , on the tops of stems and fruits, leg. A. V. Stekolshchikov”. Paratypes: 16 apterous viviparous females, 2 oviparous females, same data as holotype.

Etymology. The specific name “ epilobiphaga ” is an adjective in feminine gramatical gender derived from the genus name of host plant ( Epilobium ) and the Latin suffix “-phaga” (from Greek φάγος meaning glutton).

Description. Apterous viviparous female. Body broadly elliptical, 1.5–1.8 (1.6) times as long as wide. Living specimens gray-green or dark gray-green, with lightly waxy pulverulence; apices of antennae, hind femora, apices of tibiae, tarsi and siphunculi dark, cauda pale. Cleared specimens with frons, 1st antennal segment and siphunculi dark brown; with head (except frons), apices of 5th antennal segment, 6th antennal segment, two last segments of rostrum, coxae, sclerites in base of coxae, apices of tibiae and tarsi of all legs, intersegmental muscle sclerites on thorax, peritremes on abdominal segments, anal and subgenital plate brown; with femora (except base), tibia (except apices), and sclerites and bands on thorax and abdomen light-brown. Thorax with large weakly sclerotized marginal sclerites on pro- and mesonotum and sometimes with also very pale sclerites on pronotum formed band interrupted in the middle; abdomen not sclerotized (except peritrems) or with thin and short band or some small sclerites on abdominal tergite VIII, and very rarely with single small sclerites on tergite VII. Surface of head, dorsal side of thorax and abdominal tergites I–VI reticulate; reticulation on dorsal side of thorax and abdominal tergites I–VI hardly visible, contour of cells formed by wide irregular line. Surface of abdominal tergites VII– VIII with long rows of small pointed spinules which on tergite VIII partially fusing and forming scales. Surface of ventral side of thorax reticulate, contour of cells formed by small pointed spinules; surface of ventral side of abdomen with long rows of small pointed spinules sometimes forming strongly stretched reticulate cells. Setae on all body and appendages are finely pointed; numbers of marginal setae 1, 1–3, 1–2, 2, 1–2, 1–3, 0–1 on each side of abdominal segments I–VII, respectively. Marginal tubercles always present on prothorax and abdominal segments I and VII, conical, relatively large; rarely marginal tubercles also present on segments II–IV (number of marginal tubercles on abdominal segments II–VI—0–2 (0.5)), they are conical or papilliform, small, 2.1–5.3 times as wide as width of siphunculi in the middle. Head with epicranial suture or with clear traces of epicranial suture. Frontal tubercles low; median tubercle wide, occupies large part of frons and surpassing the level of antennal tubercles. Antennae 6-segmented; 1st, 2nd and base of 3rd antennal segment slightly wrinkled, almost smooth, 3rd (except base) and 4th–6th segments with large scales. Antennae without secondary rhinaria, and only one individual has 2–3 small round rhinaria on each of its 3rd antennal segments. Rostrum reaching mesothorax or abdominal segment I. Ultimate rostral segment elongate wedge-shaped, with slightly concave sides, 2.05–2.72 (2.41) times as long as its basal width. Legs normally developed. Chaetotaxy of first tarsal segments 3, 3, 2. Arms of mesosternal furca separated or connected by wide not sclerotized base. Spiracles reniform. Siphunculi almost cylindrical, gradually tapering towards apex, sometimes very slightly curved outvard, with relatively small, but distinct flange. Surface of siphunculi imbricated, covered by rough scales which formed by partially fused large pointed spinulae. Subgenital plate oval. Cauda finger-shaped, with slightly constriction in the middle, with rounded apex.

Measurements of the holotype. Body—1785×1115, antenna—895: III—199×23 (in middle), IV—133, V— 140, VI—91+197; hind femur—362, hind tibia—665; siphunculus— 221×52 (in middle); cauda—179×123 (at base) ×98 (before base). Additional measurements are given in Table 4.

Oviparous female. The living specimens are colored the same way as apterous viviparous females. Marginal tubercles on abdominal segments II–VI absent. Chaetotaxy of first tarsal segments 2, 2, 2, but one individual has 3 setae on one front tarsus. Arms of mesosternal furca separated. Cauda tongue-shaped, with slightly constriction in the middle, with wide rounded apex. Hind tibia hardly swollen, with 44–103 (82.0) round pheromone plates located along the entire tibia.

Distribution. Known only from the type locality— Russia, Republic of Dagestan, Tlyaratinsky District, Federal State Nature Sanctuary “Tlyaratinsky”, nearby Salda Vill.

Biology. Monoecious, holocyclic. A colony of this species consisted of apterous viviparous females and oviparous females was found on 2.ix.2023 on the tops of stems and fruits of Epilobium colchicum Albov. The colony was visited by ants.

Systematic relationships. There are 16 species of the genus Aphis living on Epilobium , of which 12 belong to the nominotypical subgenus, and 4 species to the subgenus Bursaphis . Species of the subgenus Bursaphis differ from the new species, as well as from other species of the nominotypical subgenus, by the presence of 6–12 accessory setae on ultimate segment of rostrum. The differences between apterous viviparous females of all these species and those of Aphis epilobiphaga sp. nov. are detailed in Table 5.

The closest species to the new species is A. fabae Scopoli, 1763 . Aphis epilobiphaga sp. nov. differs from A. fabae by pale cauda (cauda of A. fabae black or very dark), fewer setae on abdominal tergite VIII (usually 2 and only in one individual 6 in Aphis epilobiphaga sp. nov. and only as an exception less than 4 in A. fabae ), a smaller number of setae on the cauda (6–9 in Aphis epilobiphaga sp. nov. and 7–27, but rarely less than 11, in A. fabae ). In A. fabae , the pro- and mesonotum are almost always clearly sclerotized, and there is also a distinct band on abdominal tergite VIII and often also bands on tergites VI–VII, sclerites of various sizes on tergites I–V and postsiphuncular sclerites, while in Aphis epilobiphaga sp. nov. the pro- and mesonotum are weakly sclerotized, the band on tergite VIII is very thin and often completely disappears, the band on tergite VII is occasionally presented only in the form of a pair of small sclerites, and the band on tergite VI, sclerites on tergites I–V and postsiphuncular sclerites are always absent. These two species also differ in their life cycle— A. fabae is a dioecious species, while Aphis epilobiphaga sp. nov. monoecious.

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Figures

FIGURE 40. Apterous viviparous female of Aphis epilobiphaga sp. nov., habitus.

FIGURES 41–48. Aphis epilobiphaga sp. nov., apterous viviparous female. 41, antennae; 42, 3rd antennal segment; 43, last antennal segment; 44, head; 45, III and ultimate rostral segments; 46, hind tarsus; 47, siphunculus; 48, cauda.

FIGURE 49. Oviparous female of Aphis epilobiphaga sp. nov., habitus.

FIGURES 50–58. Aphis epilobiphaga sp. nov., oviparous female. 50, antennae; 51, 3rd antennal segment; 52, last antennal segment; 53, head; 54, ultimate rostral segment; 55, hind tibia; 56, hind tarsus; 57, siphunculus; 58, cauda.

FIGURE 59. Male of Aphis leontodontis (Börner, 1950), habitus.

FIGURES 60–67. Aphis leontodontis (Börner, 1950), male. 60, antennae; 61, 3rd antennal segment; 62, last antennal segment; 63, head; 64, III and ultimate rostral segments; 65, hind tarsus; 66, siphunculus; 67, cauda.