Kissrhizoecus hungaricus Kozár & Konczné Benedicty

Hodgson, Chris, 2012, Comparison of the morphology of the adult males of the rhizoecine, phenacoccine and pseudococcine mealybugs (Hemiptera: Sternorrhyncha: Coccoidea), with the recognition of the family Rhizoecidae Williams 3291, Zootaxa 3291 (1), pp. 1-79 : 13-16

Kissrhizoecus hungaricus Kozár & Konczné Benedicty

( Fig. 2 )

Kissrhizoecus hungaricus Kozár & Konczné Benedicty, 2005: 142 .

Material examined. Hungary, Kádárta , no host, 12.vii.2005, B. Kiss ( BMNH): 2/ 2♂♂ in fair to good condition .

Mounted material: apterous; extremely small, total body length about 440 µm, greatest width 166 µm; antennae 8 or 9 segmented, short, much less than half total body length; most flagellar segments approximately eggshaped; hair-like setae (hs) extremely similar to fleshy setae (fs); body with few setae, all hs and short, 6–15 µm long (longest posteriorly on abdomen); loculate and simple pores absent. Legs short, tarsi obscurely 2 segmented; trochanter with 2 pairs of campaniform pores and without Y-shaped sclerotisation.

Head: greatest width perhaps 100 µm; with about 9 pairs of hs dorsal head setae (dhs) distributed along full length of head; without genal setae (gs); dorsal simple eyes (dse) distinctly larger than ventral simple eyes (vse) (dse about 10 µm; vse about 8 µm); ocular sclerite (ocs) not apparently differentiated; with 2 pairs of ventral head setae (vhs) posteriorly and 2 setae along mid-line anteriorly, each about 7–8 µm long; preocular ridge (procr) absent dorsally; ventrally, procr fairly well developed and extending almost to vse.

Antennae: 8 or 9 segmented; length about 180 µm long (ratio of total body length to antennal length 1:0.41). Scape (scp): 18–22 µm long, 22–24 µm wide, with 4 hs. Pedicel (pdc): length 25 µm, width 21–23 µm; with 3 hs + a small campaniform pore. Segments III–VII ( VIII) all about 13–20 µm wide; all slightly longer than wide, with narrow intersegmental membranes; lengths of segments (µm) III–VII ( VIII) 17–24, and apical segment 35–42; fs rather similar to hs but fs apparently thicker and restricted to more apical segments; hs shorter than fs, longest fs up to 20 µm; approximate number of setae per segment: III 2 or 3 hs; IV 2 or 3 hs + 0 or 1 fs; V 0–3 hs + 2 or 3 fs; 3rd segment from apex with 3 or 4 fs + 1 antennal bristle (ab); preapical segment 2–4 fs + 0 or 1 hs + 1 larger ab; apical segment with 5 or 6 fs, 0 or 1 hs + 3 long ab + 1 placodeum basiconica.

Thorax. Prothorax: without any constriction between pro- and mesothoracic segment; setae extremely few both dorsally and ventrally; sternum (stn 1) unsclerotised but possibly with 1 pair of prosternal setae (stn 1 s); anteprosternal setae (astn 1 s) absent; antemesospiracular setae (am 2 s) with 2 or 3 setae in this position.

Mesothorax: unsclerotised; dorsum with 2 very sparse transverse bands of hs; ventrally with a few setae laterad to spiracle and a few setae (possibly postmesospiracular setae (pm 2 s)) between mesothoracic spiracle and mesocoxae. Mesothoracic spiracle (sp 2) small: width of peritreme about 7–8 µm. Furca (f) small but normally developed.

Metathorax: dorsally with a very sparse line of hs, representing metatergal setae (mts) and dorsospiracular setae (dss); ventral part of metapleural ridge (plr 3) short but well-sclerotised; metapleural ridge (plr 3) without either a metepisternum or an additional short ridge or fold extending ventrally from near coxal articulation; metepimeron (epm 3) possibly represented by a short sclerotised ridge which extend posteriorly dorsad to each metacoxae; metathoracic spiracle (sp 3): width of peritreme about 8–9 µm; metasternum (stn 3) unsclerotised, with few setae.

Wings and hamulohalteres (h) absent.

Legs: subequal in length. Coxae (cx): I 36–42; II 34–38; III 37 µm long; coxa III with about 5 or 6 hs. Trochanter (tr) + femur (fm): I 63–72; II 60–63; III 63–68 µm long; trochanter III with about 5 hs; each trochanter with 2 pairs of roundly oval sensoria, but apparently lacking Y-shaped ridges; long trochanter seta not differentiated but seta in this position about 10–12 µm long; femur III with about 6 hs. Tibia (ti): I 46–50; II 43–48; III 48–51 µm; tibia III with 5 or 6 setae, mainly short and hs, becoming spur-like ventrally towards distal end; all tibia with 2 apical spurs (tibs) but those on protibia more setose; length of longest 10–12 µm. Tarsi (ta) 2 segmented but this much less clear on anterior legs; ta 1 narrow and ring-like; length of both segments (µm): I 26–30 II 27–29; III 27–31 (ratio of length of tibia III to length of tarsus III 1:0.59); tarsus III with 5 or 6 setae, all finely spur-like ventrally; tarsal spurs not differentiated; tarsal campaniform pore apparently absent; tarsal digitules (tdgt) with blunt or slightly capitate apices and longer than length of claw. Claws (c) fairly short, slightly curved, without a denticle; length: III 12–13 µm; claw digitules (cdt) setose and slightly longer than claw.

Abdomen: segments I–VIII: tergites (at) slightly sclerotised on segments VIII and VII; sternites possibly unsclerotised; caudal extension (ce) of segment VII absent; ce on VIII rounded; setae present in a single sparse line around each segment, all short, each about 8–15 µm long; with perhaps 4 dorsal abdominal setae (ads), 1 or 2 dorsal pleural setae (dps), 1 ventral pleural seta (vps) and 6 ventral abdominal setae (avs) per segment. Segment VIII with 2 or 3 rather longer pleural setae, each about 16–22 µm long; tergite VIII with 1 pair of hs dorsal abdominal setae (ads) medially; sternite without setae or pores.

Genital segment: penial sheath (ps) large and approximately triangular, almost as wide as segment VIII and extending slightly anteriorly ventrally; with an elongate, rounded ridge dorsally that narrows to a sharp point posteriorly; anus not detected; dorsally with 2 setae on each side (each 8–10 µm long) plus another 2 laterally, each about 3–8 µm long. With a broad slit-like opening ventrally through which ps emerges; ps about 72 µm long from anterior margin to apex, 60 µm at widest point; extension about 28 µm wide. Ventrally, aedeagus (aed) emerges through ventral opening; borders of opening distinct, with 2 pairs of setae, each about 10–12 µm long + another pair of very short setae anteriorly, each about 3 µm long. Aedeagus (aed) strongly curved, perhaps 55 µm long, with a sharp apex; anteriorly, aedeagus bends ventrally and fuses with a short basal rod (bra). Penial sheath with a very few sensilla (psp) on apex.

Comment. The adult male of K. hungaricus appears to be a typical apterous rhizoecine male but differs from the other apterous species seen here in having the following combination of character states: (i) few setae on each antennal segment, with fs and hs hard to separate; (ii) body setae short and very sparse; (iii) absence of loculate and simple pores; (iv) possible absence of tarsal campaniform pores; (v) tarsal segmentation rather unclear, particularly on anterior legs; (vi) tarsal digitules with either blunt or small capitate apices, and (vii) claws short, with claw digitules equal to or longer than claw.

Figures

FIGURE 2. Kissrhizoecus hungaricus Kozár & Konczné Benedicty. Adult male. Where A = hair-like seta, B = fleshy seta, K1 = tibiotarsal articulation of anterior legs, and K2 = distal end of posterior legs. For other labels, see under Materials and methods: conventions.