Ripersiella puhiensis (Hambleton)

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 : 42-44

Ripersiella puhiensis (Hambleton)

( Fig. 13 )

Rhizoecus puhiensis Hambleton, 1974: 154 .

Ripersiella puhiensis (Hambleton) ; Matile-Ferrero, 1976: 303.

Material examined. New Zealand, Karamea , Heaphy Track, 16.iv.2005, Rata 4, ground litter, K. Affield ( NZAC): 2/ 2♂♂ in fair condition but both mounted slightly sideways .

Mounted material: apterous; very small, total body length about 670–680 µm; antennae 9 or 10 segmented, short, clearly less than half total body length; most antennal segments narrow basally, broadening distally, possibly with both hair-like setae (hs) and fleshy setae (fs) but these difficult to separate; body with few setae, all hs, fine and mainly 13–25 µm long; loculate pores (lp) with mainly 4 or 5 loculi, each about 6–8 µm wide. Legs each with 2-segmented tarsi (ta); each trochanter (tr) with 3 campaniform pores.

Head: greatest width about 120 µm. Dorsal epicranium barely sclerotised; with 12 pairs of hs dorsal head setae (dhs) distributed along full length of head, longest up to 42 µm long; with 1 pair of loculate pores but simple pores absent. With 3 genal setae (gs) posterior to each dorsal simple eyes. Simple eyes (se) round, subequal in size, each about 16 µm wide. Ocular sclerite (ocs) not apparently differentiated. Ventral epicranium also barely sclerotised, without any sign of ventral midcranial ridge (vmcr) or lateral arms of midcranial ridge (lmcr); with 6 pairs of ventral midcranial ridge setae (vmcrs), longest about 38 µm long. Preocular ridge (procr) restricted dorsally to a short ridge extending medially over dorsal simple eye; ventrally, procr present as distinct ridges which do not appear to fuse medially but extend posteriorly around each ventral simple eye.

Antennae: 9 segmented on 1 specimen, 10 segmented on other; length about 310–325 µm long (ratio of total body length to antennal length 1:0.47). Scape (scp): 30–33 µm long, 39–42 µm wide, with 4 hs. Pedicel (pdc): length 36–42 µm, width about 28 µm; with 0 fs, 8 or 9 hs but no campaniform pore detected. Segments III–X all about 20–25 µm wide at widest point; all flagellar segments broadest towards distal end; lengths of segments (µm): III 38–40; IV 23–40; V 26–28; VI 31–37; VII 30–37; VIII 31–40; non-apical segment IX 31, and apical segment 48–50; hs setae about 25–40 µm long; approximate number of setae per segment (hs and fs hard to separate): III 7 or 8 setae; IV 6 or 7 setae; V 10 setae; VI–VIII 14–16 setae + 1 antennal bristle (ab); IX (non-apical) 9–13 setae + 1 long ab, and apical segment X with about 18 setae + 3 ab; setae on segments III–VIII mainly in whorls, possibly with hs distally and fs proximally.

Thorax. Prothorax: without a constriction between either head and prothorax or between prothorax and mesothorax; with a few hs and lp + a few simple pores distributed in a narrow band across segment, representing propleural (pl 1 s) and median pronotal (mpns) setae. Sternum (stn 1) with 1 pair of hs prosternal setae (stn 1 s); also with a pair of lp + simple pores in position of anteprosternal setae (astn 1 s); antemesospiracular setae (am 2 s) possibly absent or fused to group of posterior propleural setae and lp (ppl 1 s) laterally.

Mesothorax: membranous. Dorsum with 2 narrow bands of hs + 1 lp; ventrally with a small group of setae (possibly postmesospiracular setae (pm 2 s)), lp and simple pores between furca and anterior spiracle (sp 2). Mesothoracic spiracle (sp 2): width of peritreme about 11–13 µm, each with 2 or 3 associated lp. Furca small but normally developed.

Metathorax: dorsally with a narrow band of hs + a few lp extending across full width of segment, representing metatergal setae (mts) and dorsospiracular setae (dss). Metathoracic spiracle (sp 3): width of peritreme about 11–13 µm, with 1 associated lp. Metasternum (stn 3) with a pair of hs + a pair of lp anteriorly.

Wings and hamulohalteres (h) absent.

Legs: metathoracic legs longest. Coxae (cx), lengths (µm): I 62–70; II 66–70; III 62–70; coxa III with about 10 hs. Trochanter (tr) + femur (fm), lengths (µm): I 109–125; II 103–115; III 115–130; trochanter III with about 5 hs; each trochanter with 3 roundly oval sensoria arranged in a triangle medially; with strong, Y-shaped sclerotised ridges; long trochanter seta not differentiated but seta in this position about 16–17 µm long; femur III with about 7 or 8 hs. Tibia (ti), lengths (µm): I 80–88; II 75–88; III 98–108; tibia III with 17–19 setae, mainly hs, becoming spur-like distally; all tibiae with 2–4 apical spurs (tibs); length of longest 25–27 µm. Tarsi (ta) 2 segmented, ta 1 very short and ring-like; length of both segments combined (µm): I 57–59; II 50–54; III 62–64 (ratio of length of tibia III to length of tarsus III 1:0.61); tarsus III with 16 or 17 setae, mainly spur-like; tarsal digitules (tdgt) represented by a pair of long setae, only slightly shorter than length of claw. Claws (c) long and narrow, with a hint of a small denticle about 3/4 along length; length of III 17–20 µm; claw digitules (cdt) setose, each about 10–12 µm long.

Abdomen: segments I–VIII: tergites (at), sternites (as) and pleurites (pl) distinct on segment VIII, and also with some sclerotisation on tergite VII, otherwise absent. Loculate pores (lp) absent ventrally but with 1 or 2 pores present on each side pleurally and also mediolaterally on dorsum of all segments; setae present in a single line around each segment, not obviously divided into dorsal, pleural and ventral setae, with a total of about 16–20 hs around each segment; ventral abdominal setae (avs) distinctly shorter (each about 16 µm long) than dorsal abdominal setae (ads) (each about 25 µm long). Segment VIII with a rather longer seta on each side in position of glandular pouches, each about 58–85 µm long; tergite VIII with 2 pairs of equally long hs dorsal abdominal setae (ads) mediolaterally + 1 or 2 pairs of lp; sternite without setae or pores.

Genital segment: penial sheath (ps) with a broad dorsal ridge which narrows posteriorly to a short finger-like apex; with an indistinct slit-like opening ventrally; length from anterior margin to apex about 68–75 µm, width at base 73–75 µm; apex probably upturned when viewed from side. Dorsal ridge with a wide anus anteriorly (width about 18–20 µm); also with 3 or 4 longish setae on each side, each about 10–18 µm long. Laterally with 1 pair of short setae, each about 8 µm long, and antero-ventrally with perhaps 3 pairs of setae, each 11–13 µm long. Ventrally, aedeagus (aed) strongly curved, perhaps 63–70 µm long, distal end pointed and perhaps slightly fleshy; anteriorly, aedeagus bends ventrally and fuses with a short sclerotised basal rod (bra). Apex of penial sheath with a few sensilla (psp).

Comment. The adult male of Ri. puhiensis is basically similar to the males of most of the other apterous species seen here, but differs in having the following combination of character states: (i) 9- or 10-segmented antennae, each flagellar segment broadest distally; (ii) loculate pores present dorsally on head, thorax and abdomen; (iii) simple pores present on head and thorax; (iv) each trochanter with 3 campaniform pores on each side; (v) body setae few; (vi) long setae on abdominal segment VIII subequal in length to length of penial sheath, and (vii) penial sheath without an obvious sclerotisation extending anteriorly into abdomen.

Figures

FIGURE 13. Ripersiella puhiensis (Hambleton). Adult male. Where A = hair-like seta; B = fleshy seta, C = loculate pore; D = simple pore, and K = distal end of posterior leg. For other labels, see under Materials and methods: conventions.