Paracoccus glaucus (Maskell)

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 : 64-67

Paracoccus glaucus (Maskell)

( Fig. 24 )

Dactylopius glaucus Maskell ; Maskell, 1879: 219

Pseudococcus glaucus (Maskell) ; Fernald, 1903: 102

Paracoccus glaucus (Maskell) : Cox, 1987: 64

Material examined. New Zealand, Auckland area, Waitakere Ra., Fletcher track, on Anarthropteris lanceolata (Polipodiaceae), 11.xi.2000, N.A. Martin ( NZAC: 01-020b): 1/1ad ♂ (good, except head slightly misshapen) .

Mounted material. Quite small, total body length about 1.33 mm; antennae long, more than half total body length, with long setae; body with few setae, all hair-like (hs); fleshy setae (fs) apparently absent on body; fs on antennae 3 or 4 times longer than width of antennal segments. Wings about 1.13 total body length and about 0.35 as wide as long.

Head. Misshapen; probably with a distinct postero-ventral bulge; width across genae about 285 µm. Median crest (mc) poorly demarcated and not reticulated; preoccipital ridge (por) indistinct or absent; with (on each side) about 12 hs dorsal head setae (dhs), mainly between antennae, + 2 loculate pores dorsad to each scape. Midcranial ridge: dorsal ridge (dmcr) well developed and quite broad, extending posteriorly to dorsal simple eyes (dse); ventral ridge (vmcr) narrow, extending from lateral arms (lmcr) posteriorly to just anterior to ventral simple eyes (vse); probably without any reticulations laterally. Genae (g) not reticulated; each with 2 or 3 genal setae (gs) just laterad to preoccipital ridge (procr). Eyes: with 2 pairs of round simple eyes; dorsal eyes (dse) placed well forward, each approximately dorsad to ventral simple eyes (vse), dse slight smaller than vse, dorsal eyes each 35 µm wide, ventral eyes 45 µm wide. Ocelli (o) pronounced, situated laterally; each 21–23 µm wide, lying between preoccular and post-ocular ridges (pocr). Ocular sclerite (ocs) sclerotised; only reticulated around each simple eye. Preocular ridge (procr) well developed, long, extending from inner margin of dorsal simple eyes antero-laterally to base of each scape and the postero-laterally to join post-occular ridge just ventral to each ocellus. Post-ocular ridge (pocr) strongly developed, extending from posterior to each dorsal simple eye antero-laterally past each ocellus and then fusing with the preoccular ridge before extending postero-laterally to near mouth. Interoccular ridge (ior) hinted at as a slightly more sclerotised bar dorsad to each ocellus. Dorsal ocular setae absent. Ventral head setae (vhs): 12– 17 on each side, in an elongate group between each ocellus and ventral midcranial ridge (vmcr). Preoral ridge (pror) poorly developed. Cranial apophysis (ca) not detected.

Antennae. Ten segmented and filiform; 745 µm long (ratio to total body length 1:0.56). Scape (scp) approximately square, 51–54 µm long, 54 µm wide, with 4 hs ventrally and 1 dorsally. Pedicel (pdc) 78–81 µm long, 44 µm wide, with concentric ridges on distal half; with 17–19 fs, 9–14 hs + a campaniform pore. Segments III–X all rather irregular in width, each about 19–30 µm wide; each fs 83–93 µm long; lengths of segments (µm): III 161– 166; IV 153–158; V 153–158; VI 140–145; VII 125; VIII 116–121 and IX 95. Approximate number of setae on each segment: III 16 or 17 fs + 6–11 hs; IV 21 fs + 1 or 2 hs; V 20–23 fs + 1 or 2 hs; VI 17–19 fs + 0 hs; VII 17–19 fs + 0 hs; VIII 18–21 fs, 0 hs + 1 antennal bristle (ab) about halfway along segment; IX 16 or 17 fs, 0 hs + 1 ab (about halfway along segment). Segment X not constricted apically; length 115–120 µm, with 20–25 fs, 0 hs, 2 capitate setae (caps) + 3 large ab on apical third and 1 small ab on proximal third; sensilla basiconica not detected.

Thorax. Prothorax. Pronotal ridge (prnr) well developed but not fused dorsally; pronotal sclerite (prn) represented by a small triangular sclerotisation dorsolaterally; without lateral pronotal setae. Medial pronotal setae: 3 hs + 2 or 3 loculate pores (lp) on each side; post-tergite (pt) present, probably with 1 or 2 post-tergital setae (pts). With a single lateral pronotal lp on each side; with 2 or 3 antero-spiracular dorsal setae (asds), without lp; and with 1 or 2 hs antero-spiracular ventral setae (asvs), without lp; plus a small group of 1 or 2 hs just anterior to each triangular plate. Sternum (stn 1) lightly sclerotised, without a median ridge and with transverse ridge only weakly sclerotised; with 2 hs prosternal setae (stn 1 s) + a lp on each side. Anteprosternal setae absent.

Mesothorax. Prescutum (prsc) oval, 83 µm long, 145 µm wide; sclerotised but not nodulated; prescutal ridge (pscr) well developed anteriorly but quickly fading posteriorly; prescutal suture (pscs) poorly developed; with 4 or 5 prescutal setae (prscs) on each side; with a distinct sclerotised apodeme on anterior margin of each prealare (pra). Scutum (sct) sclerotised medially, not nodulated, 83 µm long, with about 6 or 7 scutal setae (scts) on each side; each area of scutum laterad to scutellum (scl) rather square and sclerotised but not nodulated; prealar ridge (prar) quite well developed. Scutellum (scl) 99 µm wide and 79 µm long; without a scutellar ridge or foramen; with 2 hs scutellar setae (scls) on each side; pronotal wing process (pnp) thin and extending laterally. Basisternum (stn 2) 227 µm wide and 150 µm long; without a median ridge; bounded anteriorly by a weak marginal ridge (mr) medially, becoming strong laterally; posteriorly with strong procoxal ridges (pcr 2); with perhaps 20–30 hs basisternal setae (stn 2 s), mainly in a broad median band; lateropleurite (lpl) narrow, without an extension from marginal ridge along anterior margin; furca (f) well developed, narrow waisted, arms divergent and extending about halfway to marginal ridge anteriorly. Mesopostnotum (pn 2) well developed; pronotal apophyses (pna) well developed. Area bounded anteriorly by scutellum and posteriorly by mesopostnotum membranous. Mesepisternum (eps 2) not nodulated; subepisternal ridge (ser) long and well developed. Postalare (pa) without nodulations; without postalare setae. Mesothoracic spiracle with peritreme 23–25 µm wide, without associated loculate pores. Postmesospiracular setae (pm 2 s): 3 or 4 hs posterior to each spiracle. Tegular (teg) present, without tegular setae (tegs).

Metathorax. With 3 or 4 metatergal setae (mts), well spaced; metapostnotal sclerite (pn 3) distinct. Dorsal part of metapleural ridge (plr 3) present, but presence of suspensorial sclerites uncertain. Posterior part of metapleural ridge well developed; metepisternum (eps 3) not sclerotised and without postmetaspiracular setae; precoxal ridge (pcr 3) well developed, extending medially; metasternal apophyses distinct. Metepimeron (epm 3) sclerotised but without setae. Antemetaspiracular setae absent. Metathoracic spiracle (sp 3) with peritreme 25 µm wide, with a single loculate pore just posterior to each spiracle. Dorsospiracular setae absent. Metasternum (stn 3) membranous, with 2 pairs of hs anterior metasternal setae (amss) and 2 pairs of posterior metasternal setae (pmss).

Wings. Hyaline, 1500 µm long, 540 µm wide (ratio of length to width 1:0.34; ratio of total body length to wing length 1:1.15); alar lobe (al) well developed; each wing with 3 hs alar setae (als) + 3 circular sensoria (sens). Hamulohalteres (h) each 96–100 µm long, 20 µm wide, with a single apical hamulus 53–60 µm long.

Legs. Metathoracic legs longest. Lengths (µm): coxae (cx): I 103–110; II 100; III 116; setae on III about 11 fs + 7–10 hs; long setae on each coxa not differentiated. Trochanter (tr) + femur (fm): I 302; II 294–300; III 303; trochanter III with about 8–11 fs + 3 hs; each trochanter with 3 campaniform pores arranged in a triangle medially, and with strong, sclerotised Y-shaped ridges for articulation with femur; long trochanter seta not differentiated; femur III with about 35–39 fs + 2–6 hs. Tibia (ti): I 306; II 311; III 356–360; tibia III with about 55–57 setae, mainly fs, a few becoming spur-like at distal end of leg; with 3 apical spurs (tibs) on each protibia; 5+ on each mesotibia and 7 or 8 on each metatibia; length of longest about 23–25 µm. Tarsi (ta) all 2 segmented; length of both segments combined: I 107–114; II 103–108; III 115–121 (ratio of length of tibia III to length of tarsus III 1: 0.33); tarsus III with 30–39 setae, mainly spur-like; tarsal spurs not differentiated; tarsal campaniform pore present; tarsal digitules (tdgt) capitate and shorter than claw; tibio-tarsal articulation distinct. Claws (c) each long and thin, nearly twice width of tarsus, almost straight, without a denticle; length ( III) 41–43 µm; claw digitules (cdt) short and finely setose.

Abdomen. Segments I–VII: tergites (at) and sternites (as) unsclerotised and without obvious oval membranous areas in inter-segmental areas. Caudal extension on segment VII absent. Dorsum without loculate pores. Each segment with a total of 4–7 dorsal setae (ads); dorsopleural setae (dps) on each side: I 3 hs + 3–6 loculate pores (lp) + 0–2 small simple pores; II 3hs + 1 or 2 lp; III & IV 3 hs + 1 lp; V & VI 3 hs +0 lp; VII 4 or 5 hs + 0 lp; ventral pleural setae (vps) on each side: I 1 hs; II–VII 2 hs. Ventral setae (avs) (totals): II–VII 3–7 hs. With a pair of indistinct ostioles laterally between segments VI and VII.

Segment VIII: tergite (at) lightly sclerotised medially; sternite (as) with a small sclerotisation anterolaterally; tergite with 1 pair of hs ante-anal setae; sternite with 1 pair of avs; caudal extension (ce VIII) very rounded with 7–9 hs pleural setae. Glandular pouches (gp) shallow, each with numerous loculate pores spreading out around pouch; each pouch with 2 long glandular pouch setae (gls), each about 300 µm long, plus a shorter third seta about 56 µm long.

Genital segments. Penial sheath (ps) possibly slightly distorted: short, triangular and blunt; anal opening not detected but probably present just posterior to tergite IX on dorsal surface; no other structures noted on dorsal surface. Ventrally, apex of ps (style) bluntly pointed, about 10 µm long. Length of ps from anterior border to apex 100 µm, width across basal ridge 89 µm. Basal ridge (brps) well developed; lateral processes of penial sheath distinct, each with 4 or 5 short setae; also with 4 short hs anterior to each lateral process (pro) and 3 pairs of longer setae near posterior border. Basal rod (bra) distinct, about 25 µm long to top of aedeagus (aed), extending anteriorly to about halfway to basal ridge. Aedeagus (aed) parallel sided at base but broadening slightly towards apex, extending almost to end of penial sheath; aed 56 µm long, about 17 µm wide at apex.

Comment. The adult male of another Paracoccus species ( P. marginatus ) has been described previously ( Miller & Miller, 2002). The adult males of these two species are very similar but differ as follows (character states of P. marginatus in brackets): (i) all fleshy setae on antennae long and rather setose (short and blunt); (ii) tegular setae absent (present); and (iii) loculate pores absent near anterior spiracles (present). As can be seen, these differences are small. Although the anus could not be detected on P. glaucus , it is in the normal pseudococcoid position on P. marginatus , at the posterior end of tergite IX (see Fig. 24N ).

Tribe: uncertain.

Figures

FIGURE 24. Paracoccus glaucus (Maskell). Adult male. Where C = loculate pores; D = simple pore; J = dorsal view of posterior end of abdomen; K1 = tibio-tarsal articulation; K2 = claw; L = ventral view of posterior end of abdomen, and N = side view of penial sheath of P. marginatus Williams (latter modified after Miller and Miller, 2002). For other labels, see under Materials and methods: conventions.