Kermes echinatus, Balachowsky

Porcelli, Francesco & Pellizzari, Giuseppina, 2014, Description of female nymphal instars and adult female of Kermes echinatus Balachowsky (Hemiptera, Coccoidea, Kermesidae) based on specimens from Crete and mainland Greece, with a discussion on geographical variation, Zootaxa 3878 (1), pp. 61-74 : 62-64

KERMES ECHINATUS Balachowsky

Kermes echinatus Balachowsky, 1953: 183 –184.

FIRST INSTAR NYMPH (crawler) ( Fig.1 ). Described from 5 specimens in good condition; details checked on another 20 specimens (11 from Crete, 1 from Athens, 13 from Kalamata).

Living specimen: oval and almost flat, orange-red.

Mounted specimen: cuticle membranous, body oval, 500 (440 –640) Μm long, 230 (200–300) Μm wide at thorax.

Dorsum. Marginal setae 32–34 on each side in two lines almost superimposed, each seta spine-like and slightly bent, 8–18 Μm long, basal socket 4–6 Μm wide; usually with a line of longer spines 17 (16–18) Μm long alternating with a line of smaller spines, 11 (8–14) Μm long, (plate 1, b, c, d). Dorsal setae: four trichoid setae, each 7–9 Μm long, in a submedial longitudinal row on each side of head and thorax. Microtubular ducts detectable near each inter-segmental fold and present also on head. Anal lobes small, lightly sclerotized, each with two spine-like setae on inner margin. Apical setae each 216 (210–224) Μm long.

Venter. Dermal spinules present medially on abdomen and thorax. Eyes found near margin. Antennae 6- segmented, each 94–96 Μm long; scape with 2 trichoid seta; pedicel with 2 trichoid setae; 3rd segment with 1 trichoid seta; 4th segment with one chaetic seta; 5th with 2 trichoid and 1 chaetic setae; apical segment with 4 or 5 long trichoid setae and 2 chaetic setae. One small trilocular pore present near the scape of each antenna. Labium triangular in shape, 3-segmented, 66–67 Μm long, basal and second segments each with one pair of setae, third segment with 4 pairs. Stylets longer than body, looped within a crumena, shorter arm extending anteriorly as far as anterior coxa. Legs well developed, with two diamond-shaped sensilla on each trochanter. Tarsal and claw digituli knobbed, longer than claw. Thoracic spiracles small and narrow, with one associated spiracular pore, each about 3.5 Μm wide with 5, rarely 7, loculi; two bilocular pores, circular and about 2–3 Μm wide, present on body margin between spiracles; one trilocular (rarely pentalocular) pore present near margin of prothorax and another on body margin opposite anterior spiracle. Pairs of trilocular pores, each about 3 Μm wide, found medially on head (one pair), on each thorax segment and on abdominal segments V–VII. With 3 pairs of trichoid setae present medially on frons and one pair of short setae medially on each thoracic segment; other trichoid setae in 6 longitudinal rows on abdominal segments: setae in medial rows each 10–16 Μm long; sub-medial setae each 8–10 Μm long and submarginal setae each 4.5 Μm long. Anal lobes small, anal ring horse-shoe shaped, 14 Μm wide, with a few cells and 6 setae, each 10–12 Μm long; with one anterolateral seta on each side of anal ring, each 10 Μm long, plus one postero-lateral seta on each side of anal ring, each 16 Μm long.

Comments. Among the Mediterranean and European Kermes , the first-instar nymphs of K. echinatus , K. vermilio and K. hermonensis Ben-Dov & Spodek are easily distinguishable from other first-instar Kermes species by the presence of marginal spine-like setae. In K. vermilio the marginal spine-like setae are conical, stouter and straight, whereas in K. echinatus and K. hermonensis the marginal spine-like setae are distinctly longer and slightly bent. Moreover, K. echinatus has 62–68 marginal spines whereas K. hermonensis differs by having only 42–48 spines.

The presence of microtubular ducts near the inter-segmental folds is also reported by Baer & Kosztarab (1985) in Nearctic Kermesidae 1st -instars (e.g. K. concinnulus Cockerell , K. cockerelli Ehrhorn , K. rimarum Ferris ) but are referred as “dorsal simple pores”. However, according to the drawings of Baer & Kosztarab (1985: 131, 175, 184, 197), these pores are clearly microtubular ducts.

SECOND-INSTAR FEMALE NYMPH ( Fig. 2 ). Described from 5 specimens in good condition; details checked on another 5 specimens (1 from Crete, 2 from Athens, 7 from Kalamata).

Living specimen: not seen

Mounted specimen: body oval, 1 mm (0.8–1.2) long, 0.7 mm (0.5–0.9) wide (plate 1, e).

Dorsum. Marginal setae conical, spine-like and stout, of one size, each 11 (10–14) µm long, 6 Μm wide at base, basal socket 8 µm wide; with about 29–32 on each margin. Small conical setae, each about 5–6 µm long, sometimes bent, sparse; also a few small trichoid setae, sparse. Tubular ducts, similar to ventral tubular ducts, present on body margin and sparsely throughout. Microtubular ducts numerous and scattered throughout. Anal lobes fused.

Venter. Cuticle crenulated medially on abdomen, thorax and head. Eyes located antero-laterally to each antenna, misshapen in mounted specimens. Antennae 1–3 segmented, sometimes with indistinct segmentation; 3- segmented antennae about 46–48 Μm long and 16 Μm wide at base, scape usually with 2 very short setae, second segment with one seta; third segment with 6 or 7 chaetic setae on apex; monomerous antennae 16–20 µm long, with 6 or 7 chaetic setae on apex. Frontal lobes present, “sausage-shaped”, about as long as 3-segmented antennae (plate 2, g). Labium triangular, 112 (96–130) Μm long, 3 segmented, basal and second segments each with one pair of setae, third segment with 4 pairs. Legs very reduced, tubercle-like, usually with 2 or 3 short setae. Spiracles well developed, sclerotized; each anterior spiracle with peritreme 24 (16–30) Μm wide, usually with 2 associated spiracular disc-pores, each 4 Μm wide with 5 loculi; each posterior spiracle with peritreme 23 (13–30) Μm wide, with 1 or 2 associated spiracular pores. Bilocular pores, each about 2 Μm wide, sparsely distributed on submargin of abdomen. Tubular ducts each 12 (8–16) Μm long and 3 wide, with thin inner ductule, distributed in a wide marginal band, sparse on thorax and head and present on each abdominal segment; and thinner tubular ducts, with the opening of outer ductule narrower than its inner end (plate 2, p), each 16 Μm long and 1.5 Μm wide, inner ductule about 12 Μm long, present mostly on head near labium. Ventral trichoid setae of variable length, 5–14 Μm long, irregularly distributed on abdominal segments and sparse on head and thorax. Anal lobes small, each with one small conical seta and one apical seta, 40 (27–64) Μm long. Anal ring rounded, 24–30 Μm wide, with pores and 6 setae, each about 27–34 Μm long.

Comments. Kermes echinatus second-instar females mainly differ from those of K. vermilio ( Pellizzari et al., 2012) as follows (characters of K. vermilio in brackets): 1–3-segmented antennae (5-segmented); and with 58–64 marginal spine-like setae (68–74). Both species have frontal lobes and small, tubercle-like legs. K. hermonensis second-instar females differ from those of both K. vermilio and K. echinatus in having 3-segmented legs and 3–6- segmented antennae (Spodek & Ben-Dov, 2014).

Other described second-instar females of Kermes species from Europe and the Mediterranean are those of K. bytinskii and K. quercus ( Sternlicht, 1969; Podsiadlo, 2012; Spodek & Ben-Dov, 2014) which have 5 or 6- segmented antennae, and short, 3-segmented legs; these characters are shared with the second-instar females of the Nearctic K. cockerelli Ehrhorn , K. concinnulus Cockerell and K. rimarum Ferris ( Baer & Kosztarab, 1985) .

THIRD-INSTAR FEMALE NYMPH ( Fig. 3 ). Described from 13 specimens in good condition; details checked on another 7 specimens (3 from Crete, 6 from Athens, 11 from Kalamata).

Living specimen: body rounded, convex, bright yellow just after moult, otherwise orange- brown, with numerous protruding white waxy tufts on dorsum (plate 1: a)

Mounted specimen: body rounded, 1.8 (1.6–2) mm long and 1.5 (1.4–1.6) mm wide, slightly tapering posteriorly (plate 1: h).

Dorsum. Marginal setae spine-like, conical, of one type, with 26–32 setae on each margin, each seta 17 (14–19) Μm long and about 9.6 Μm wide at base. Dorsal setae either small conical or trichoid, irregularly present throughout. Microtubular ducts scattered throughout. Tubular ducts, each 15–16 Μm long, about 5 Μm wide, with inner ductule 14 long, rare, mostly near body margin.

Venter. Cuticle medially crenulated on head, thorax and abdomen. Eyes located antero-laterally to each antenna, misshapen in mounted specimens. Antennae short, monomerous, tubercle-like, about 30 Μm long and 22 Μm wide, with 2 short setae at base and a group of 5–8 chaetic setae, each 22–27 Μm long, on apex. Frontal lobes present, not very pronounced, about as long as antennae. Labium sub-triangular, 140 Μm long and 90 wide at base, 3-segmented, basal and second segments each with one pair of setae, third segment with 4 pairs. Anterior legs each reduced to a tubercle, with 3–5 short setae; other pairs of legs entirely absent, or indistinct and represented only by groups 2 or 3 short setae. Spiracles well developed, each anterior peritreme about 22 Μm wide, usually with 2 (1–4) associated spiracular disc-pores, each about 4 Μm wide with 5 or 6 loculi; each posterior spiracle with peritreme 30 Μm wide, with 2 (0–3) associated spiracular disc-pores; bilocular (seldom trilocular) pores, each about 3 Μm wide, present on abdominal submargin. A few specimens with 1–3 isolated multilocular pores on last abdominal segments. Tubular ducts of two sizes: large ducts, each 15–16 Μm long, 5 Μm wide, with inner ductule 14 Μm long, distributed in a wide marginal band, and sparsely medially on thorax and head and each abdominal segment; and thin tubular ducts, each 14–16 Μm long and 2–3 Μm wide, with the opening of outer ductule narrower than its inner end, present medially on head and thorax (plate 2, p). Trichoid setae 6–18 Μm long, with basal socket 2 Μm wide, irregularly distributed on abdominal segments and sparse on head and thorax. Anal lobes fused; anal lobe setae each 44 Μm long; auxiliary setae 21 (15–30) Μm long. Anal ring almost circular 32–36 Μm wide, with pores and 6 setae, each 22–32 Μm long; with three pairs of suranal setae, each 16 (10–23) Μm long.

Comments. Third-instar female K. echinatus differ from those of K. vermilio mostly as follows (characters of K. vermilio in brackets): monomerous antennae (2- or 3-segmented); and with about 50–60 marginal spine-like setae (132–222). The third instar females of K. hermonensis differ from those of both K. vermilio and K. echinatus in having 3-segmented legs and 5- or 6-segmented antennae (Spodek & Ben-Dov, 2014).

Comparison and comments on a few other non-European Kermes 3rd -instars are reported in Pellizzari et al. (2012) and in Spodek & Ben-Dov, 2014.

ADULT FEMALE ( Fig. 4 ). Described from 5 specimens in good condition, details checked on another 16 specimens (9 from Crete, 2 from Athens, 10 from Kalamata).

Unmounted specimens: pre-reproductive females, found dead on twigs, brown-yellowish, with transverse wrinkles on dorsum. Reproductive female sub-spherical, dark, with transverse wrinkles on dorsum and red eggs inside body cavity.

Mounted specimen: body of pre-reproductive female largely oval or rounded, tapering posteriorly, 2.8 (2.2–3.2) mm long and 2.6 (2–3) mm wide (plate 2, r).

Dorsum. Marginal setae spine-like, conical‚ of one type, each 16 (14–20) Μm long, 6–8 Μm wide at base, with 28–34 on each margin. Dorsal setae all conical, spine-like setae, each 13–14 µm long and 5–6 µm wide at base, unevenly distributed over dorsum. Large tubular ducts, each about 19–22 Μm long and 4–5 Μm wide, inner ductule 12 (8–16) Μm, numerous and scattered. Microtubular ducts sparse throughout.

Venter. Cuticle crenulated medially on abdomen and thorax. Antennae short, tubercle-like, one segmented, each 28 (22–34) Μm long, 23 (20–26) Μm wide, with a group of 5–8 chaetic setae, about 20–24 Μm long, at apex. Eyes located antero-laterally to each antenna, misshapen in mounted specimens. Clypeolabral shield 234 (213–250) Μm long. Labium subtriangular, 166 (160–170) Μm long and 102 (90–110) Μm wide, 3-segmented, basal and second segments each with one pair of setae, third segment with 4 pairs. Legs absent. Spiracles well developed and sclerotized, each anterior spiracle 60 Μm wide, each posterior spiracle 75 Μm wide. Multilocular pores (plate 2, n)‚ each about 8 Μm wide with 10–12 loculi, forming a large group near each antenna and with 14–18 near each spiracle; multilocular pores also in transverse bands on all abdominal segments and around vulva. Bilocular pores each about 3 Μm long, sparse throughout. Tubular ducts of two/three sizes: larger ducts each about 12–20 Μm long and about 4–5 Μm wide, inner ductule 8–16 Μm long, distributed in a wide marginal band, sparse medially on thorax and head and medially on each abdominal segment; and a thinner duct, with opening of outer ductule narrower than inner end, each about 16 Μm long and 2.4–3 Μm wide, more frequent than larger type medially on frons, around labium and medially on thorax and abdomen (plate 2, o, q). Ventral trichoid setae each 6–24 Μm long, irregularly distributed across abdominal segments, plus a few medially and submedially on head and thorax, these usually shorter than on abdominal segments. Anal lobes not found. Apical seta each 47 (40–56) Μm long. Anal ring circular and sclerotized, 48 (40–56) Μm wide, with 6 setae, each 40 (36–44) long plus 3 pairs of suranal setae, each 19 (13–25) Μm long.

Figures

FIGURE 1. Kermes echinatus Balachowsky: first instar nymph.

FIGURE 2. Kermes echinatus Balachowsky: second instar nymph, female.

FIGURE 3. Kermes echinatus Balachowsky: third instar nymph, female.

FIGURE 4. Kermes echinatus Balachowsky: adult female.