Macrosiphum eastopi Barjadze & Blackman, 2017

Barjadze, Shalva, Barbagallo, Sebastiano, Blackman, Roger & Özdemir, Işil, 2017, A new Caryophyllaceae-feeding species of Macrosiphum (Hemiptera: Aphididae) in Republic of Georgia, and a redescription of Macrosiphum hartigi Hille Ris Lambers, Zootaxa 4341 (2) : 235-241

Redescription of Macrosiphum hartigi Hille Ris Lambers, 1947

Figs 14–18 , 20–24 , Table 2

as Macrosiphum montanum in Hille Ris Lambers, 1931: 20 ; 1935: 63 and 1939: 95 as Macrosiphum hartigi in Hille Ris Lambers, 1947: 319

Material examined. Co–types: 19 apt., coll. no. BM 1984-340, north–eastern ITALY, Bolzano province, Collalbo, N 46°32', E 11°27', 1142 m a.s.l., 31.viii.1930, on Silene inflata (= S. vulgaris ), leg. D. Hille Ris Lambers (at BMNH); Other material: 5 apt. and 2 al., coll. no. BM 1984-340, north–eastern ITALY, Trento province, Madonna di Campiglio, N 46°13', E 10°49', 1522 m a.s.l., 27.vi.1933, on Silene inflata (= S. vulgaris ), leg. F. Hartig (at BMNH); 17 apt., coll. no. 3059, north–eastern ITALY, Udine province, Lusevera, N 46°16', E 13°16', 456 m a.s.l., 31.v.1986, on Silene vulgaris , leg. S. Barbagallo (at UCI); 2 apt., coll. no. BM 1984-340, SWITZERLAND, canton of Valais, Zeneggen, N 46°16', E 7°51', 1384 m a.s.l., without date, on Silene vulgaris , leg. A. Stäger (at BMNH); 1 apt. and 4 al., coll. no. 2822, FRANCE, Utelle, N 43°55', E 7°14', 792 m a.s.l., 11.v.1969, on Stellaria holostea , leg. F. Leclant (at IEC); 2 al., coll. no. BM 1984-340, AUSTRIA, Innsbruck, N 47°16', E 11°22', 716 m a.s.l., 11.vi.1950, on Silene vulgaris , leg. D. Hille Ris Lambers (at BMNH); 1 f., coll. no. 4209, SWITZERLAND, Airolo, N 46°31', E 8°36', 1215 m a.s.l., 27.v.1956, on Silene inflata (= S. vulgaris ), leg. W. Meier (at BMNH); 4 ov., coll. no. 12,226/9, SWITZERLAND, Arosa, N 46°46', E 9°40', 1737 m a.s.l., 13.x.1968, on Linum alpinum , leg. W. Meier (at BMNH); 7 m., coll. no. 6141, ITALY, Trento province, Vigo di Fassa, N 46°25', E 11°40', 1429 m a.s.l., 15.ix.2004, on Silene vulgaris , leg. S. Barbagallo (at UCI); 3 m., coll. no. 7811, ITALY, Cuneo province, Crissolo (Pian del Re)–, N 44°42', E 7°5', 2011 m a.s.l., 14.ix.2011, on Silene vulgaris , leg. S. Barbagallo (at UCI).

Description. Fundatrix (n=1)

Appearance in life: unknown. Appearance on slide: ANT I–III pale; ANT IV and V darker towards apices; ANT VI wholly dark; head, thorax and abdomen pale, without any dark sclerotisation; URS dark; SIPH dark at apices; cauda pale ( Fig. 14 ).

Slide–mounted specimen: body oval ( Fig. 14 ), medium sized, BW 0.59× BL. ANT 6–segmented, ANT tubercles weakly developed. ANT III with three small sec. rhin. on basal half (other ANT missing). Rostrum short, reaching to middle coxae. SIPH cylindrical, smooth, with enlarged base and small flange; apical reticulated area covering about 0.12 part of the length of SIPH and slightly constricted. SIPH length 4.65× its middle diameter. Cauda elongated tongue–shaped with very slight constriction at basal 1/3. Other characters as in apterous viviparous female.

Apterous viviparous female (n=44)

Appearance in life: Body green with faint covering of greyish wax; ANT yellowish brown; apices of tibiae and tarsi dark brown or black; SIPH pale green with blackish apices; cauda green ( Hille Ris Lambers 1939). Appearance on slide: ANT I and II pale or pale brown, pigmentation of flagellar segments variable, always progressively darker distally; ANT III either wholly pale except for dark at apex only, or only pale at base with both sensoriated part and apex dusky or dark; ANT IV pale or darker towards apex or wholly dark; ANT V dark distally or wholly dark; ANT VI wholly dark; head, thorax and abdomen pale; abdomen without any dark sclerotisation; URS dark; legs either mainly pale or with distal parts of femora and most part of tibiae dusky/dark, tibial apices and tarsi very dark brown/black ( Fig. 22 ); SIPH mainly pale with usually dark apices or completely dark except pale basal part; cauda pale ( Fig. 15 ).

Slide–mounted specimens: body oval or spindle–shaped ( Fig. 15 ), medium sized, BW 0.49–0.64× BL. ANT 6– segmented ( Fig. 15 ), ANT tubercles well developed ( Fig. 15 ). ANT setae pointed ( Fig. 20 ). Sec. rhin. present on one side of ANT III over most of its length, numbering 10–24 all of similar size, almost in a single row. Cephalic setae pointed. Cuticle of head capsule and ANT I usually smooth, except for a few very small spicules occasionally present on ventral side lateral to mouthparts. Rostrum short, reaching to or just passing middle coxae. URS oblong triangular with blunt apex ( Fig. 21 ). HFEM with very small and spiculated imbrications usually visible on their distal two–thirds. Small MTu usually present on most of ABD TERG II–VI. ABD TERG VII–VIII each with 0–2 small STu. SIPH cylindrical, smooth, with enlarged base and small flange ( Fig. 24 ); apical reticulated area covering 0.09–0.22 part of the length of SIPH and slightly constricted. SIPH length 5.98–12.06× its middle diameter. Subgenital plate widely oval and sclerotized. Cauda elongate triangular and slightly constricted at basal 1/3 ( Fig. 23 ).

Alate viviparous female (n=8)

Appearance in life: As in apterous viviparous females, but head and thorax brown and abdomen with brown marginal spots; SIPH brown ( Hille Ris Lambers 1939). Appearance on slide: ANT dark except for pale base of ANT III; head dark; coxae, trochanters and basal halves of femora pale; femora darker on distal halves and very dark towards apices; tibiae pale or pale brown on proximal two–thirds and dark on about distal third, with very dark tibial apices or tibiae completely dark; tarsi dark; abdomen pale, without any dark dorsal sclerotisation except for small pale brown marginal sclerites; SIPH pale basally, becoming gradually darker distally or completely dark; cauda pale ( Fig. 17 ).

Slide–mounted specimens: body spindle–shaped ( Fig. 17 ), medium–sized, BW 0.41–0.47× BL. ANT 6– segmented ( Fig. 17 ), ANT tubercles well developed. Sec. rhin. present on one side of ANT III over most of its length, numbering 18–35 all of similar size, almost in a single row. Cuticle of head capsule and ANT I usually smooth, except for a few very small spicules occasionally present on ventral side lateral to mouthparts. HFEM with small spiculated cuticular imbrications on distal one–third to half of length. SIPH cylindrical, smooth, with enlarged base and very small flange; apical reticulated area covering 0.16–0.20 part of the length of SIPH and slightly constricted. SIPH length 8.00–11.85× its middle diameter. Other characters as in apterous viviparous female.

Oviparous female (n=4)

Appearance in life: unknown. Appearance on slide: pigmentation very similar to apterous viviparous female, except that hind tibiae are sometimes darker over most of length ( Fig. 16 ).

Slide–mounted specimens: body oval or broadly spindle–shaped ( Fig. 16 ), medium sized, BW 0.55–0.61× BL. ANT 6–segmented, ANT tubercles well developed. Sec. rhin. present on one side of ANT III over most of its length, numbering 3–12 all of similar size, almost in a single row. Cuticle of head capsule and ANT I usually smooth, except for a few very small spicules occasionally present on ventral side lateral to mouthparts. HFEM with very small and spiculated imbrications usually visible on their distal two–thirds. HTIB slightly swollen, with ca. 60–200 scent plaques. SIPH with apical reticulated area covering 0.12–0.17 part of the length of SIPH and slightly constricted. SIPH length 6.94–9.45× its middle diameter. Other characters as in apterous viviparous female.

Alate male (n=10)

Appearance in life: unknown. Appearance on slide: Head and thorax brown; ANT brown except for the base of ANT III, which is slightly pale; legs brown except for the paler, basal part of femora and the extensive median part of tibiae; SIPH pale brown, but darker towards apex; abdomen with sclerotised marginal areas on ABD TERG I–VI (VII), and median sclerified bands (sometimes more or less broken) on ABD TERG I–VIII; cauda brown ( Fig. 18 ).

Slide–mounted specimens: body spindle–shaped ( Fig. 18 ), medium sized, BW 0.34–0.39× BL. ANT 6– segmented, ANT tubercles well developed. Number of sec. rhin. on ANT III: 5 5–75, on ANT IV: 0–4 and on ANT V: 11–23. Cuticle of head capsule and ANT I usually smooth, except for a few very small spicules occasionally present on ventral side lateral to mouthparts. Rostrum short, reaching to middle coxae. HFEM with small spiculated cuticular imbrications on distal half to two–thirds. Small MTu present on ABD TERG II–V. ABD TERG VII–VIII often with 2 STu. SIPH with apical reticulated area covering 0.21–0.27 part of the length of SIPH and distinctly constricted. SIPH length 8.42–11× its middle diameter. Other characters as in apterous viviparous female.

Measurements, ratios and chaetotaxy for the above–described morphs are given in Table 2.

Life cycle. Macrosiphum hartigi is a monoecious holocyclic species. Its recorded host plants are Silene vulgaris and Stellaria holostea ( Blackman & Eastop 2017) , except the specimens from Linum , which were examined for the description of oviparous females. On Silene vulgaris , it lives on the upper part of flower stalks and under the leaves ( Hille Ris Lambers 1931, 1939).

Distribution. Macrosiphum hartigi is recorded from Austria, France, Italy, and Switzerland ( Holman 2009).

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Discussion Apterous viviparous females of M. eastopi resemble those of M. hartigi in the arrangement of sec. rhin. over most of the length of ANT III, and in the ratio of the URS/HT II. However, they can be distinguished by the SIPH/cauda ratio: 1.55–1.94 in M. eastopi , while 1.22–1.58 in M. hartigi . The SIPH/cauda ratio also separates the alate viviparous females: 1.83–2.11 in M. eastopi , while 1.24–1.68 in M. hartigi . Alatae also differ in the number of sec.

rhin. on ANT III: 36–43 in M. eastopi , while 18–35 in M. hartigi . Alate males of the new species are again distinguishable from those of M. hartigi by the SIPH/cauda ratio: 2.25–2.54 in M. eastopi , while 1.68–2.00 in M. hartigi . In addition, the species are geographically separated – the new species lives in the Greater Caucasus Mountains, while M. hartigi lives in the Alps and they use different host plants; M. eastopi feeds on Oberna multifida , whereas M. hartigi is mostly recorded on Silene vulgaris ( Silene and Oberna are closely–related genera). Apterous viviparous females of M. eastopi sp. n. are distinguished from those of the other three Macrosiphum species that feed on Caryophyllaceae ( M. euphorbiae , M. penfroense and M. stellariae ) by (1) the number and distribution of sec. rhin. on ANT III: 13 or more sec. rhin. extend over most of length of ANT III in M. eastopi , whereas in M. euphorbiae , M. penfroense and M. stellariae , 1–12 sec. rhin. are concentrated on basal half of ANT III; (2) the URS/HT II ratio: 0.63–0.84 in M. eastopi , whereas the other three species have 0.8–1.0 ( Heie 1994; Stroyan 1979). In addition, apterous viviparous females of M. eastopi are distinguished from the same morph of M. euphorbiae by (1) the number of setae on the anterior part (disc) of the subgenital plate: 6–18 in M. eastopi , while 2–4 in M. euphorbiae ; (2) the number of setae on the cauda: 14–19 in M. eastopi , while 8–12 in M. euphorbiae . Macrosiphum eastopi differs from the same morph of M. stellariae by the number of setae on the cauda: 14–19 in M. eastopi , while 8–15 in M. stellariae ( Heie 1994) .

Alate viviparous females of M. eastopi sp. n. have more sec. rhin. on ANT III (36–43) than those of M. euphorbiae , M. penfroense and M. stellariae (6–33); and alate females of M. eastopi also have a URS/HT II ratio below 0.8, whereas the other 3 species have more than 0.8.

Alate males of M. eastopi sp. n. are distinguished from the same morph of M. euphorbiae and M. stellariae by (1) the URS/HT II ratio: 0.73–0.81 in M. eastopi , while 0.78–0.93 in M. euphorbiae and M. stellariae ; and (2) the SIPH/BL ratio: 0.18–0.20 in M. eastopi , while 0.21–0.27 in M. euphorbiae and M. stellariae ( Watson 1982; Heie 1994; Blackman 2010).

There are four aphid species previously recorded from Oberna multifida ( Dzhibladze 1960, 1968; Andreev & Mamontova 1998; Ӧzdemir & Barjadze 2015): Aphis gossypii Glover , Brachycaudus divaricatae Shaposhnikov , Brachycaudus lychnidis (Linnaeus) and Macrosiphum stellariae Theobald.

Figures

FIGURES 14 – 19. Habitus of different morphs of Macrosiphum hartigi Hille Ris Lambers, 1947 and Macrosiphum eastopi Barjadze & Blackman sp. n. Macrosiphum hartigi. Fundatrix (bar: 1 mm); 15. Apterous viviparous female from co-type series (bar: 1 mm); 16. Oviparous female (bar: 1 mm); 17. Alate viviparous female (bar: 1 mm); 18. alate male (bar: 1 mm); Macrosiphum eastopi sp. n. 19. alate male (bar: 500 µm).

FIGURES 20 – 24. Macrosiphum hartigi Hille Ris Lambers, 1947. apterous viviparous female. 20. ANT III (bar: 200 µm); 21. Rostral segments II – V (bar: 200 µm); 22. Tarsus (bar: 200 µm); 23. Cauda (bar: 200 µm); 24. SIPH (bar: 200 µm).