Uroleucon (Lambersius) robinsoni, Barjadze, Shalva & Kanturski, Mariusz, 2020

Barjadze, Shalva & Kanturski, Mariusz, 2020, Two new species of the aphid genus Uroleucon (Hemiptera: Aphididae) living on Grindelia in the USA, European Journal of Taxonomy 729, pp. 42-53 : 44-47

Uroleucon (Lambersius) robinsoni sp. nov.

urn:lsid:zoobank.org:act:C7C38DD0-01C5-4BB4-9938-1D3CD3D8A81A

Figs 1–2 , Table 1

Diagnosis

Apterous viviparous females of Grindelia -feeding Lambersius have the following combinations of characters: PT 4.66–6.50×BASE; ANT III with 12–21 secondary rhinaria ( Fig. 2 a–b); URS 1.061.33 ×BASE and 1.18–1.25×HT II with 7–9 short, fine, pointed accessory setae ( Fig. 2d ); HT I with 5:5:5 setae; SIPH subcylindrical, slightly tapering without a flange ( Fig. 2e ); its reticulated zone 0.170.28 ×SIPH. SIPH 2.30–2.68 ×cauda and 0.31–0.41 ×BL; scleroites on setal bases absent on ABD I–V, while setae on ABD VI–VIII arise from barely visible, rounded scleroites; cauda narrow finger-shaped without constriction and with 7–9 setae ( Fig. 2f ).

Etymology

We are very pleased to name the new species in honor of A.G. Robinson (University of Manitoba, Canada), who worked on the North American Macrosiphini .

Material examined

Holotype

USA • ♀ apterous viviparous; Colorado, Carson Hole ; 38°43′ N, 108°36′ W; alt. 2348 m; 16 Sep. 1956; Hottes and Hille Ris Lambers leg.; Grindelia squarrosa ; NHMUK 010121495 .

Paratypes

USA • 2 ♀♀ apterous viviparous; same collection data as for holotype; NHMUK 010121495 • 2 ♀♀ apterous viviparous; same collection data as for holotype; NHMUK 010121496 • 2 ♀♀ apterous viviparous; same collection data as for holotype; DZUS 010121481 • 2 ♀♀ apterous viviparous; same collection data as for holotype; NHMUK 010121482 .

Description

Apterous viviparous female (n = 9)

COLOR IN LIFE. Unknown.

PIGMENTATION OF CLEARED SPECIMENS ON SLIDE. Body generally membranous, pale to yellow; ANT brown with pale ANT I–II and basal part of ANT III; coxae and trochanters pale; femora yellow with light brown distal ends; tibiae brown with paler middle section or pale with only distal part darker; tarsi light brown; SIPH yellow with light brown to brown distal ends; cauda pale ( Fig. 1a ).

MORPHOMETRIC CHARACTERS. HW 0.17–0.19 ×ANT. Head with thick, rigid setae with blunt or narrowly capitate apices, 0.030 –0.040 mm long. ANT tubercles each with 2–3 setae. ANT 0.83–1.04× BL. ANT III with 12–21 rounded secondary rhinaria of different sizes, with sclerotized rims ( Fig. 2 a–b), ANT IV longer than ANT V. PT 4.66–6.50 ×BASE ( Fig. 2c ). Other antennal ratios: VI:III 1.13–1.28, V:III 0.61– 0.70, IV:III 0.70–0.76, PT:III 0.93–1.11, PT:IV 1.22–1.47 and PT:V 1.32–1.69. ANT bearing medium length thick, rigid setae with blunt or narrowly capitate apices. ANT III setae 0.020 –0.045 mm long, LS ANT III 0.84–1.13×BD III. ANT I with 4–5, ANT II with 3–4, ANT III with 12–21, ANT IV with 8–12, ANT V with 7–9 setae. ANT VI with 3 basal, 4 apical and 2–5 setae on PT. Rostrum reaching middle coxae in some specimens to as far as hind coxae in other specimens. URS 0.21–0.24×ANT III, 0.17–0.20×ANT VI, 0.20–0.24 ×PT, 1.06–1.33× BASE and 1.18–1.25 ×HT II with 7–9 short, fine and pointed accessory setae ( Fig. 2d ). Mesosternal furca fused, wide, T-shaped. Hind femora bearing medium length, thick, rigid setae with narrowly capitate or slightly pointed apices, 0.020 –0.040 mm long. Hind tibiae bearing thick, rigid setae, most slightly pointed or blunt, shorter than width of tibiae, 0.025 –0.045 mm long. In some specimens, tibiae bearing few pseudosensoria. HT I with 5:5:5 setae, HT II 0.18–0.19×ANT III, 0.14–0.16 ×ANT VI, 0.16–0.20 ×PT and 0.86–1.08 ×BASE. SIPH subcylindrical, slightly tapering and curved externally with distinct zone of subapical reticulation and without flange ( Fig. 2e ). Reticulated zone 0.17–0.28×SIPH. SIPH 2.30–2.68 ×cauda, 0.31–0.41× BL, and 1.38–1.57×ANT III. Abdomen membranous with medium length, thick rigid setae with narrowly capitate or blunt apices, 0.025 –0.040 mm long on ABD I–V and 0.030 –0.040 mm long on ABD VI– VIII. ABD VIII with 4 setae. Scleroites on setal bases absent on ABD I–V, while setae on ABD VI–VIII arising from very poorly visible, rounded and pale scleroites. Genital plate with two anterior setae longer than others, 7–10 posterior setae. Cauda narrow finger-shaped without constriction, 2.05–2.75 ×its width at base and 0.13–0.15 ×BL with 7–9 fine setae ( Fig. 2f ).

Remarks

Of the six Grindelia -feeding aphids of Uroleucon , only U. penderum Robinson, 1986 , U. robinsoni sp. nov. and U. grindeliae sp. nov. have shared characters: (1) ANT III has the majority of the secondary rhinaria on the basal half and (2) their URS/HT II ratio is 1.15 or more and (3) the coxae and trochanters are pale ( Robinson 1986; Blackman & Eastop 2020).

The apterous viviparous females of Uroleucon robinsoni sp. nov. differ from the same morphs of U. penderum : (1) their SIPH/CAUDA L ratio is 2.30–2.68 in U. robinsoni sp. nov., while it is 1.65–1.95 in U. penderum , (2) their URS/HT II ratio is 1.18–1.25 in U. robinsoni sp. nov., while it is 1.3–1.6 in U. penderum , (3) the pigmentation of the tibiae is dusky or dark for most of their length in Uroleucon robinsoni , while their tibiae are pale except at the apices in U. penderum ( Blackman & Eastop 2020) .

The apterous viviparous females of the two new species differ from each other in the following characters: (1) their ANT PT/BASE ratio is 4.66–6.50 in U. robinsoni sp. nov., while it is 3.31–3.61 in U. grindeliae sp. nov., (2) their SIPH/CAUDA ratio is 2.30–2.68, while it is 1.37–1.77 in U. grindeliae sp. nov. and (3) their cauda is finger shaped with no constriction in U. robinsoni sp. nov. ( Fig. 2f ), while it is tongue shaped with an evident constriction near the base in U. grindeliae sp. nov. ( Fig. 3f ).

Biology and distribution

The species was collected from Grindelia squarrosa in Colorado, USA. Other morphs and the life cycle of the new species are unknown.

Figures

Fig. 1.New speciesofUroleucon Mordvilko, 1914feeding on Grindelia Willd. a. Uroleucon (Lambersius) robinsoni sp. nov., holotype, apterous viviparous female (NHMUK 010121495) b. U. (L.) grindeliae sp. nov., holotype, apterous viviparous female (NHMUK 010121473) c. U. (L.) grindeliae sp. nov., paratype, alate viviparous female (NHMUK 010121477).

Fig. 2. Uroleucon (Lambersius) robinsoni sp. nov., holotype, apterous viviparous female (NHMUK 010121495). a. ANT III. b. Secondary rhinaria on ANT III. c. ANT VI. d. Ultimate rostral (III–V) segments. e. Siphunculus. f. Cauda.

Fig. 3. Uroleucon (Lambersius) grindeliae sp. nov., paratype, apterous viviparous female (NHMUK 010121474). a. ANT III. b. Secondary rhinaria on ANT III. c. ANT VI. d. Ultimate rostral (III–V) segments. e. Siphunculus. f. Cauda.