Ripersiella kondonis (Kuwana)

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 : 37-39

Ripersiella kondonis (Kuwana)

( Fig. 11 )

Rhizoecus kondonis Kuwana, 1923: 55 .

Material examined. Japan, Wakayama, -. xi.1922, on roots of orange ( Citrus , Rutaceae ) K(uwana) ( BMNH): 1/ 1♂ in good condition.

Mounted material: apterous; very small, total body length about 780 µm, greatest width 295 µm; antennae 7 segmented, short, much less than half total body length; most flagellar segments almost round, with both hair-like (hs) and fleshy setae (fs), latter distinct, quite long, with a blunt apex; body fairly hirsute, all hs, very variable in length, some short (21+ µm long), others quite stout, and up to 80+ µm long; loculate pores (lp) with mainly 4 or 5 loculi, each lp about 6–7 µm wide; simple pores absent. Without either ocelli or simple eyes; tarsi (ta) 1 segmented; trochanter with 2 pairs of campaniform pores.

Head: greatest width about 125 µm. Dorsal epicranium apparently unsclerotised; with about 18 pairs of hs dorsal head setae (dhs) and 3 or 4 pairs of loculate pores (lp) distributed along full length of head; simple pores absent. Simple eyes and ocelli both absent. Ocular sclerite (ocs) not apparently differentiated. Ventral epicranium also apparently unsclerotised, without any sign of ventral midcranial ridge (vmcr) or lateral arms of midcranial ridge (lmcr); with 5 pairs of ventral midcranial ridge setae (vmcrs), longest about 15–17 µm long. Preocular ridge (procr) absent dorsally; ventrally, procr represented by thin ridges that extend medially and possibly fuse; also apparently with an additional pair of ridges which extend posteriorly a short distance from procr mediolaterally.

Antennae: 7 segmented; length about 260 µm long (ratio of total body length to antennal length 1:0.34). Scape (scp): 42 µm long, 36 µm wide, with 4 hs. Pedicel (pdc): length 41–43 µm, width 36 µm; with 4 or 5 fs + 11 hs + a small campaniform pore. Segments III–VI all about 23–28 µm wide, all slightly wider than long, with narrow intersegmental membranes; apical segment wide, about 33 µm; lengths of segments (µm): III–VI 16–20, and VII 45; fs each 21–26 µm long; hs rather variable but longest up to 80 µm and shortest about 20 µm long; approximate number of setae per segment: III 3 fs + 6 hs (2 long); IV 3–5 fs + 6 hs (2 long); V & VI 5 or 6 fs, 5 or 6 hs (5 long) + 1 rather plump antennal bristle (ab), and VII 12 fs, 15 hs (several long) + 3 rather plump ab; hs on segments II–VI mainly in whorls.

Thorax. Prothorax: slightly swollen laterally; hs and a few lp distributed in a narrow band across segment. Sternum (stn 1) with 2 pairs of lp in position of prosternal setae (stn 1 s); anteprosternal setae (astn 1 s) and antemesospiracular setae (am 2 s) probably absent.

Mesothorax: unsclerotised. Dorsum with two narrow bands of hs, anterior band with a few lp; ventrally with a small group of setae and lp between furca (f) and mesothoracic spiracle (possibly postmesospiracular setae (pm 2 s)). Mesothoracic spiracle (sp 2): width of peritreme about 14 µm.

Metathorax: dorsally with a narrow band of hs + 1 pair of lp extending across full width of segment, representing metatergal setae (mts) and dorsospiracular setae (dss). Metapleural ridge (plr 3) without either a metaprecoxal ridge or an additional short ridge extending ventrally from near coxal articulation. Metepimeron (epm 3) represented by a pair of short sclerotised ridges which extend posteriorly above metacoxae. Metathoracic spiracle (sp 3): width of peritreme about 14–15 µm, with 2 associated lp. Metasternum (stn 3) with a pair of setae + 1 lp anterior to each metacoxa.

Wings and hamulohalteres (h) absent.

Legs: metathoracic legs longest. Coxae (cx): I 70–72; II 66–68; III 68–70 µm long; coxa III with about 7 hs. Trochanter (tr) + femur (fm): I 103; II 98; III 115 µm long; trochanter III with about 5 hs; each trochanter with 2 roundly oval sensoria in a line parallel to trochanterofemur articulation, but without strong Y-shaped sclerotised ridges; long trochanter seta not differentiated but seta in this position about 25 µm long; femur III with about 8 hs. Tibia (ti): I 60; II 63; III 78 µm long; tibia III each with 11 setae, mainly hs, becoming spur-like ventrally towards distal end; all tibiae with 2 apical spurs (tibs); length of longest 27 µm. Tarsi (ta) 1 segmented; length (µm): I 50; II 43; III 53 µm long (ratio of length of tibia III to length of tarsus III 1:0.68); tarsus III with 5 setae, all spur-like ventrally, with more proximal ventral spur very long, about 30 µm long; tarsal spurs not differentiated; tarsal digitules (tdgt) setose, much shorter than length of claw. Claws (c) long and narrow, without a denticle; length: III 33 µm; claw digitules (cdt) very short and setose.

Abdomen: segments I–VIII: tergites (at) unsclerotised; sternites (as) present on segments VII and VIII; pleural areas unsclerotised. Caudal extension (ce VIII) on VIII rounded. Loculate pores (lp) absent ventrally but with 0 or 1 lp present on each side laterally; setae present in a single line around each segment, ventral setae (avs) more setose and much shorter (each 16–20 µm long) than dorsal abdominal setae (ads) (each 20–40 µm long); with a total of about 8 or 9 ads and 4–6 avs across each segment; division into dorsal (dps) and ventral pleural setae (vps) not clear, but probably with 2 very long dps and 1 shorter avs plus 1 lp per segment. Each caudal extension (ce VIII) with 1 rather long seta, about 75–80 µm long; tergite VIII with 7 hs dorsal abdominal setae (ads) medially and a pair of lp laterally on each side; sternite without setae or pores.

Genital segment: penial sheath (ps) extending some way anteriorly under segments VIII and VII, but posterior margin rounded, not divided; with a dorsal finger-like ridge, pointed posteriorly, but apex broken; length from anterior margin to broken apex about 125 µm, width 78 µm at widest point; finger-like dorsal ridge about 33 µm wide. Dorsal ridge with a wide anus (a) anteriorly (width about 18 µm) and also with 3 longish setae on each side, each about 28 µm long, plus another pair of shorter setae near apex laterally. Ventrally with a broad slit-like opening through which aedeagus (aed) emerges; borders of opening quite heavily sclerotised, with 3 pairs of long setae, each about 30 µm long. Aedeagus strongly curved, perhaps 75 µm long, with apex apparently bifid; anteriorly, aedeagus bends ventrally and fuses with a short sclerotised basal rod (bra). Presence of sensilla (psp) on apex unknown as apex broken.

Comment. Along with those of Ri. malschae (Williams) and Ripersiella sp. A , both described below, the adult male of Ri. kondonis differs significantly from other apterous rhizoecine males seen during this study. In particular, they differ in having: (i) no eyes; (ii) only a single tarsal segment; and (iii) trochanter with only 2 pairs of campaniform pores. In addition, Ri. kondonis has: (i) an aedeagus with a bifid apex; (ii) metatarsi with a particularly large ventral spur, and (iii) head with an additional pair of ridges extending posteriorly from preocular ridge. Ri. kondonis is, none-the-less, otherwise a typical rhizoecine male (see diagnosis). For comparisons with Ri. malschae and Ripersiella sp. A , see under those species below.

Figures

FIGURE 11. Ripersiella kondonis (Kuwana). Adult male. Where A = hair-like setae; B = fleshy seta; C = loculate pore; K = distal end of posterior leg, and P = apex of aedeagus. For other labels, see under Materials and methods: conventions.