Chorizococcus multiporus, Gertsson & Hodgson

Hodgson, Chris, 2005, The adult males of Coccoidea (Hemiptera: Sternorrhyncha) known from Greenland, Zootaxa 907, pp. 1-48 : 9-14

CHORIZOCOCCUS MULTIPORUS Gertsson & Hodgson ( Fig. 2 )

Chorizococcus multiporus Gertsson & Hodgson, 2005: 6 .

(Described from 5 specimens, mostly in fair condition, a few moderately good; some details checked on remaining specimens).

Live appearance: not recorded.

Mounted material: apterous; small and elongate, total body length about 0.81–0.92 mm; antennae slightly more than half total body length, with short, stout fleshy setae (fs); length of fs on antennae rather less than width of antennal segments; body with few setae, all hair­like (hs), fs setae apparently absent; loculate pores (lp) each with mainly 3–5 loculi, each pore about 5µm wide; many with a nearby minute pore. Abdomen with only 1 pair of glandular pouches.

Head: roundly triangular, apex of triangle pointing anteriorly; with ventral eyes probably on a distinct postero­ventral bulge; length about 153–166µm; width across genae about 170–183µm. Median crest (mc) absent; postoccipital ridge (por) absent; with (on each side) about 9–13 hs dorsal head setae (dhs) + 0 or 1 lp mesad to each scape. Midcranial ridge: dorsal ridge (dmcr) distinct, long and narrow, extending posteriorly well past posterior margin of dorsal simple eyes (dse); ventral midcranial ridge (vmcr) short but well defined, without any reticulation laterally; with 2 or 3 hs ventral midcranial ridge setae (vmcrs). Genae (g) not reticulated; with 3 or 4 hs genal setae (gs) on each side. Eyes: two pairs of round, simple eyes, subequal in size; dorsal eyes (dse) each approximately level with ventral simple eyes (vse); dorsal eyes each 26–27µm wide, ventral eyes each 24–27µm wide. Ocelli (o) fairly pronounced, situated laterally, each 13– 20µm wide, lying just dorsad to where interocular ridge (ior) and postocular ridge (pocr) meet. Ocular sclerite (ocs) lightly sclerotised, with reticulations restricted to immediately around simple eyes. Preocular ridge (procr) very short on both dorsal and ventral surfaces but fusing with interocular ridge (ior) posterior to each scape. Postocular ridge (pocr) strongly developed, extending antero­laterally, ending just dorsad to dse; ventrally each fusing with ior just ventral to each ocellus. Dorsal ocular setae (docs) absent. Ventral head setae (vhs): with 6–10 hs in a transverse line anterior to vse plus 2 or 3 pairs of hs between eyes. Preoral ridge (pror) and cranial apophysis (ca) probably absent.

Antennae: 10 segmented and filiform; 490–535µm long (ratio of total body length to antennal length 1:0.59). Scape (scp) slightly wider than long: 39–48µm long and 39– 52µm wide, with 2 hs ventrally and 2 hs dorsolaterally. Pedicel (pdc): length 56–58µm, width 38–42µm; with concentric ridges on distal end; with 5–14 fs + 5–10 hs; campaniform pore present. Segments III–X each about 25–33µm wide; lengths of segments (µm): III: 51–60; IV: 46–50; V: 41–53; VI: 46–53; VII: 48–56; VIII: 54–58; IX: 50–56; fs about 16–22µm long; approximate number of setae per segment: III: 6–12 fs + 2–7 hs; IV: 11 or 12 fs + 2–7 hs; V: 10–15 + 2–4 hs; VI: 6–14 fs + 3–5 hs (significantly longer on this and more distal segments than on more basal ones, but without capitate apices); VII: 10–12 fs + 4 or 5 hs; VIII: 8–10 fs, 5 or 6 hs + 1 bristle (abr); IX: 7–9 fs, 5 or 6 hs + 1 bristle (abr). Segment X without a constricted apex: length 66–83µm; with 6 or 7 long setae, probably caps but mainly without capitate apices, plus about 6–9 fs, 1 hs + 3 bristles (abr) near apex (these barely differentiated from fs); with 1 or 2 sensilla basiconica (sb) near apex.

Thorax. Almost entirely membranous. Prothorax: pronotal ridges (prnr) well developed but not fused dorsally; long, extending ventrally and nearly touching proepisternum + cervical sclerite (pepcv); pronotal sclerite (prn) represented by a small finger­like projection extending postero­laterally; without lateral pronotal setae (lpns). Medial pronotal setae (mpns): on each side 0–3 hs + 0–3 lp; post­tergite (pt) and postergital setae (pts) absent but with 5 hs along posterior margin of segment. With 3–8 hs lateral prothoracic setae (lps) + 5–8 lp per side. Sternum (stn1) unsclerotised; median ridge absent, transverse ridge lightly sclerotised probably without apophyses; with 1 hs prosternal setae (stn1s) + 0 or lp per side. Anteprosternal setae (astn1s) and pores absent. Proepisternum + cervical sclerite (pepcv) strongly developed; with 1 hs antemesospiracular setae (asp2s) + 0–2 lp per side.

Mesothorax: entirely membranous, all sclerotisations associated with wings absent. Dorsally with 4–13 hs + 0–2 lp on each side medially. Ventrally with a group of 10–16 hs + 1–5 lp medially. Mesothoracic sternal apophyses (furca) quite well developed. Laterally with 4–6 pleural setae. Mesothoracic spiracle (sp2): width of peritreme 16–20µm, with a group of 1 or 2 hs + 1–5 lp postmesospiracular setae (pm2s) just posterior to spiracle. Mesopleural ridge (plr2) and mesepisternum (eps2) strongly developed and quite broad. A small sclerotised concavity present in pleural area laterad to each mesocoxa.

Metathorax: entirely membranous; dorsally with a total of 7 or 8 hs metatergal setae (mts) + 2 or 3 lp. Ventrally with 0–3 hs anterior metasternal setae (amss) + 1–4 lp on each side, and 1–3 hs posterior metasternal setae (pmss) + 0–2 lp on each side. Metapleural ridge (plr3) quite long, without a precoxal ridge (pcr3) extending medially. Metepisternum (eps3) probably absent. Metasternum (stn3) membranous; metasternal apophysis (st3a) distinct. Metepimeron (epm3) moderately long and strongly sclerotised. Metathoracic spiracle (sp3): width of peritreme 16–20µm, without associated lp. Postmetaspiracular setae (sp3s) and pores absent. A small sclerotised concavity present in pleural area laterad to each posterior spiracle. Metapleural setae 4–6 hs on each side; with 2–4 hs anterior metasternal setae (amss) + 0 or 1 lp, and 0 or 1 hs posterior metasternal setae + 0 or 1 lp on each side.

Legs: metathoracic legs marginally longest. Coxae (cx): I: 71–95; II: 78–88; III: 76– 95µm long; setae of coxa III: about 9–15 hs; long setae on each coxa not differentiated. Trochanter (tr) + femur (fm): I: 175–205; II: 170–197; III: 175–200µm long; trochanter III with about 4–7 hs; each trochanter with 3 circular sensoria on each side arranged in a triangle medially and with strong sclerotised ridges for articulation with femur; long trochanter seta 50–60µm long; femur III with about 16–21 hs, some up to 33µm long. Tibia (ti): I: 142–168; II: 149–185; III: 166–208µm; tibia III with a total of about 16–23 setae, of which 0 or 1 fs (shorter than thinner than those on antennae); several others becoming spur­like on distal third of leg; with 2 or 3 spurs (tibs) on protibia, 1 or 2 on mesotibia and 2 or 3 on metatibia, strongest 23–28µm long. Tarsi (ta) two segmented, proximal segment very short and ring­like, length of both segments combined: I: 73–90; II: 85–88; III: 86– 100µm long (ratio of length of tibia III to length of tarsus III 1:0.50); tarsus III with 12–18 setae, mainly spur­like + 0–2 fs; tarsal spurs (tabs) not differentiated, but seta in this position about 18–20µm long; tarsal campaniform pore (tcp) present; tarsal digitules (tdt) as long as claw, with small capitate apices. Claws (c) long and thin, slightly longer than width of tarsus, almost straight, without a small denticle (cd); length: III: 20–27µm; claw digitules (cdt) setose and much shorter than claw.

Abdomen: segments I–VII: tergites (at) and sternites (as) unsclerotised. Caudal extension (ce) of segment VII absent. Dorsal abdominal setae (ads) (totals across segment): segment I–V: 8 or 9 hs + 0 lp; VI & VII: 2–4 hs + 0 lp. Pleural setae: dorsopleural setae (dps) on each side: I: 1 hs + 1 lp; II–VII: 2 hs + 0 lp (1 seta on VII rather longer, 35– 50µm); ventropleural setae (vps) (on each side): II–VI: 2 hs + 0 lp; VII 1 hs + 0 lp. Ventral abdominal setae (avs) (totals): II: 2–4 hs + 0 lp; III–VII: 4–6 hs + 0 lp. With a pair of indistinct ostioles (os) laterally between segments VI and VII.

Segment VIII: tergite (at) and sternite (as) mainly sclerotised; tergite without dorsal abdominal setae (ads) (rarely a single hs); sternite without ventral abdominal setae (avs); caudal extension (ce) rounded, with 2 hs pleural setae. Glandular pouches (gp) present, shallow, each with numerous loculate pores spreading out around glandular pouch (gp); with 2 rather long glandular pouch setae (gls), each about 80–125µm long, plus 2 shorter setae, each about 50–65µm long.

Genital segment: penial sheath (ps) short, broadest anteriorly, sides converging to a fairly narrow, blunt apex; covered dorsally by a narrow, elongate membranous area becoming sclerotised posteriorly, probably representing segment IX; with a vertical anal opening (an) at posterior end, about 20–25µm wide. Length of penial sheath 70–100µm, greatest width 75–92µm. Ventral lateral processes of penial sheath well developed, each with 3 short setae; ventral surface with 2 other pairs of short setae, each about 8–9µm long; with 3 pairs of longer setae (each 16–25µm long) laterally near apex. Basal rod (bra) short but distinct, probably lying more or less vertically, perhaps about 16–20µm long to top of aedeagus (aed) (including heavily sclerotised area which probably represents internal genital aperture (iga)). Aedeagus (aed) more or less parallel­sided, extending to end of penial sheath, about 60–66µm long and about 12µm wide, C­shaped, lying within penial sheath.

Material examined: GREENLAND: Thule, Location 38, 27.vii.1951, Chr. Vibe: 1/ 1adΨ; Muslingerbugt, Jameson Land, 26.vii.1994, Jens Böcher: 2/4adΨΨ; Zackenberg, Station 7C, 8.vii.2002, Jens Böcher: 1/2adΨ; as previous, 8.vii.2000: immɗ; as previous, 4.viii.1999: 3adΨΨ; as previous, 19.viii.2002, Nat. Env. res. Stat.: 2/4ΨΨ + 1 crawler; as previous, 29.vii.2002: 2/1adɗ, 1 immɗ + 2 crawlers; as previous, Station 3F, 5.viii.2002: 1/adΨ + 1 immɗ; as previous, Station 7D, 12.viii.2002: 1/crawler; no locality, 2.viii.1999, no collector: 3/8ΨΨ ( ZMUC; BMNH; USNM).

Comment. So far, this is the only species with apterous males in Greenland. The identity of the male is reasonably certain based on its similarity to C. altoarcticus and its having been collected at the same time as a female.

Males of the type series of C. altoarcticus Richards (Richards, 1965) were also seen during this study. The males of C. multiporus appeared to be almost identical, even though the adult females are rather different ( Gertsson & Hodgson, 2005). The structure of the males of C. altoarcticus agree reasonably well with the description of Richards (1964) except that he illustrated the males as lacking glandular pouches (present on the type series) and suggested in the text that they had 8 setae on each scape (4 only) and that the antennae were without fleshy setae (present).

The males studied here varied quite significantly in size, thus the wide range of measurements.

Figures

FIGURE 2. Adult male of Chorizococcus multiporus Gertsson & Hodgson. Where G = multilocular disc­pores; H = minute pore; J = apical antennal segment; K = latero­ventral view of genital segment; M = lateral sclerotisation.