Heteromargarodes americanus Jakubski, 1965

Hodgson, Chris & Foldi, Imre, 2006, A review of the Margarodidae sensu Morrison (Hemiptera: Coccoidea) and some related taxa based on the morphology of adult males, Zootaxa 1263 (1), pp. 1-250 : 1-250

Heteromargarodes americanus Jakubski

( Fig. 9 )

Heteromargarodes americanus Jakubski, 1965: 85 .

Material studied

USA: Idaho, Hansen, Pole 32, Trap 3, June 25 1931, Wind vane trap ( USNM: 34 295): 1/1ad ♂ (in good condition). However, as pointed out by Jakubski (1965), who mentions this specimen in his original description (although his collection data are slightly different), this male may not actually belong to H. americanus as it was not collected with the original type series .

Mounted material

Fairly large, 2.78 mm long, and 0.6 mm wide across prealare. With a pair of large compound eyes which meet ventrally. Body setae few, apparently all with shallow basal sockets, appearing rather stiff and straight, with finely blunt apices, none very long (range 5–65 m); collared setae (cs), hairs (hrs), loculate pores (lp) and convex pores (cp) absent. Antennae quite short; long antennal setae randomly distributed, often with satellite setae (sats). Most sclerotised areas nodulated. Legs well developed but with anterior legs fossorial; front femur rather setose but without bifurcated setae (bs); legs otherwise not very setose; spur­like setae not differentiated on any tibia or tarsus; tarsi 1 segmented; claws without a denticle; claw digitules acute. Abdominal segment I not visible ventrally; with tubular pores on segments VI and VII; without lateral caudal extensions. Penial sheath strongly sclerotised, rather quadrate; aedeagus with an eversible endophallus.

Head

Broadly oval in dorsal view, length about 180 m, width across compound eyes 350 m. Dorsally with a small, well­developed, somewhat triangular postoccipital suture (pos) on posterior margin, with 3 small setae. Dorsal epicranium (dmep) with a short, diamond­shaped dorsomedial sclerotisation anteriorly between antennae and a more heavily sclerotised area along posterior margin; rest of dorsal surface membranous. Postocciput (poc) absent. Midcranial ridge (mcr) absent. Dorsal head setae (dhs) and pores absent. Laterally with a pair of large compound eyes (cde), each about 250 m long and more or less oval in shape, but much broader ventrally, where they more or less meet; each with about 65 ommatidia. Each compound eye (cde) with a narrow, lightly sclerotised, ocular sclerite (ocs) along posterior margins, each with a single ocellus (o) dorsolaterally, 33 m wide. Preocular ridge (procr) present along antero­ventral margin of compound eye. Postocular ridge (pocr) present along dorsal margin and posterior to each ocular sclerite (ocs); sclerotised ventral projection (p) probably short. Ventrally with a diamond­shaped ventromedial part of epicranium (vmep) anterior to compound eyes, with a strong midcranial ridge (vmcr) extending posteriorly from between antennae to ventral plate (vp), although possibly incomplete about half­way along; vmep with 11 or 12 setae on each side (each 8–35 m long); rest of vmep membranous. Cranial apophysis (ca) apparently absent. No structures representing tentorial arms, tentorial bridge (tb) or tendon­like apodeme detected, but mouth (m) clearly visible on posterior margin of ventral plate (vp). Ventral plate (vp) rather quadrate and mostly sclerotised, extending posteriorly onto prothorax; vp with 5 setae of variable length. Ventral sclerites (vs) absent or fused to anterior end of cervical sclerites (cv).

Antennae: 10 segmented; length 1.26 mm (ratio of total­body length to antennal length 1:0.45). Scape (scp) 103–110 m long, 90–95 m wide, sclerotised; with about 14 very short setae basally on dorsal surface and 15 larger, stiff setae, each about 30–50 m long, more distally. Pedicel (pdc) 66–86 m long, 82–86 m wide, articulating with scape; with about 29 setae, mostly moderately short; no campaniform sensilla (camp) or coeloconic sensilla (cos) detected. Segments III–X each somewhat swollen, particularly along outer margin; greatest width (segment IV) 95 m; each segment with 27–48 long setae (each 53–85 m long); each long seta with 0 or 1 (usually 0, rarely 2) satellite setae (sats); short hair­like setae (hs) rare; segments III–XI each with 1–3 larger bristles (ab) + 2–7 short bristles on outer and dorsal surfaces; coeloconic sensilla (cos) not detected. Segment X elongate oval; capitate setae absent. Segment lengths (m): III 112, IV 140–157, V 157–166, VI 165–170, VII 165, VIII 157–166, IX 165–170 and X 157.

Thorax

Prothorax: separated from head by a broad neck with little indication of a cervical groove. Dorsally with a more or less quadrate pronotal plate (prn) immediately posterior to postoccipital suture (pos). Also with a pair of quite large post­tergites (pt), which extend longitudinally. Laterally with anterior and posterior areas of pleural sclerotisation. Ventrally with a pair of strong cervical sclerites (cv) which probably articulate anteriorly with postocular ridge (pocr) and ventral projection (p). Pleural ridge (plr 1) short, extending dorsally from articulation with coxa; pleural apophysis (pla 1) distinct. Ventrally: prosternum (stn 1) only mildly sclerotised, without a longitudinal ridge and with no transverse ridge; without prosternal apophyses (st 1 a). Pores absent on prothorax. Setae as follows: median pronotal setae (mpns): with 13 setae on each side; each post­tergite with about 10 post­tergital setae; with 1 seta on each side of prescutum; pleural areas with 17 anterior propleural setae (apl 1 s) on each side, each 8–30 m long, and about 8 (somewhat obscured by prothoracic legs) posterior propleural setae (ppl 1 s) on each side; anteprosternal setae (astn 1 s) in a band of about 30 extending across anterior part of prothorax. Antemesospiracular setae (asp 2 s) absent.

Mesothorax: dorsally: prescutum (prsc) large and more or less oval (length 270 m, width at widest point 280 m), with a nodulated surface; mesoprephragma (phr 1) short; prescutal ridges (pscr) short; prescutal sutures (pscs) forming posterior margin; without prescutal setae (prscs). Scutum (sct) sclerotised throughout and lightly nodulated, without a median membranous area; distance from prescutum to scutellum about 165–190 m; with a group of about 22 scutal setae (scts) on each side medially. Scutellum (scl) triangular to diamond­shaped; without oval membranous areas laterally; scutellum with 0 or 1 scutellar setae (scls) on each side. Large membranous area of mesopostnotum (pn 2) present; mesopostnotal apophyses (pn 2 a) quite large. Laterally: prealare (pra) elongate, extending latero­ventrally to meet mesepisternum (eps 2); tegula (teg) large and sclerotised, with a group of 17–20 tegular setae (tegs); in addition, there appears to be a small sclerite between prealare and mesepisternum, approximately in position of triangular plate (tp) on more advanced coccoids. Mesopleural ridge (plr 2) well developed, with a shallow pleural apophysis (pla 2). Mesepisternum (eps 2) nodulated. Mesothoracic spiracles (sp 2): width of peritremes 58– 60 m. Ventrally: basisternum (stn 2) large, nodulated, extending posteriorly rather more than usual; length 415 m, width 415 m; with a total of 45 setae, present throughout; median ridge (mdr) only slightly developed posteriorly; anteriorly without a distinct marginal ridge (mr) but this ridge very well developed anterolaterally between basisternum and lateropleurite (lpl); posteriorly with well­developed precoxal ridges (pcr 2); furca (f) moderately narrow posteriorly, without a waist but with short arms which diverge strongly; lateropleurite (lpl) approximately triangular in shape, bounded ventrally by a broad marginal ridge (mr), posteriorly by a broad precoxal ridge (pcr 2) and laterally by a strong extension of subepisternal ridge (ser); each lpl with a group of 10 or 11 setae. Without postmesospiracular setae (pm 2 s). Wing sclerites: apparently similar to other members of this group but costal complex of veins (ccx) rather strongly developed.

Metathorax: dorsally, metapostnotum (pn 3) present as a pair of large sclerites, each with a narrow arm which extends pleurally towards apex of pleural ridge; with 22 or 23 metatergal setae (mts) on each side extending across segment. Laterally: dorsospiracular setae (dss) absent. Suspensorial sclerites (ss) well developed. Pleural ridge (plr 3) well developed; precoxal ridge (pcr 3) well developed and extending medio­ventrally almost to metasternum (stn 3). Metepisternum (eps 3) present as a sclerotisation on ventral side of metapleural ridge (plr 3); metepimeron (epm 3) absent. Posterior spiracles (sp 3): width of peritremes about 40– 48 m. Ventrally: metasternum (stn 3) sclerotised, approximately triangular, with short, narrow lateral apophyses (stn 3 a). Postmesoprecoxal setae (ppcr 2 s) in small groups of 2 or 3; anterior metasternal setae (amss): total about 17 (each 18–80 m long); posterior metasternal setae (pmss): 4–6 on each side on metasternite.

Wings: large and well developed; length about 2.38 mm; width unknown (ratio of total­body length to wing length 1:0.85). Subcostal thickening (sclt) well developed; wing anterior to sclt only lightly sclerotised; rest of wing membranous; with a line of 11–14 circular sensoria (sens) along subcostal thickening; alar setae (als) absent; radius (rad) and media (med) veins apparent as faint sclerotisations; alar fold (af) indicated by less sclerotisation. Alar lobe (al) well developed but small and unsclerotised. Hamulohalteres (h) quite broad medially; bent about 1/3 along length; mainly sclerotised, with a strong vein along anterior margin; length 300–305 m, width 108–125 m; with 1 blunt apical hamulus (ham), about 25 m long, which bends posteriorly.

Legs: prothoracic legs fossorial, markedly different from meso­ and metathoracic legs. Prothoracic legs as follows: lengths (m): coxae (cx) 285–290; trochanter (tr) + femur (fm) 457–460; tibia (ti) 100–105 and tarsus (ta) 62–65. Coxa (cx) with about 43 small setae near base + about 30 longer setae distally. Trochanter with about 12 hs but without a long flagellate seta; trochanter (tr) with a group of 8–11 campaniform sensilla (camp) on each lateral surface near coxal articulation. Femur (fm) with about 75 setae of rather variable length (5–65 m); bifurcated setae (bs) absent. Tibia (ti) with a few spur­like setae along ventral margin; bifurcated setae (bs) absent; with about 28 setae elsewhere; each with 2 short tibial spurs (tibs), each 20–25 m long. Tarsi (ta) 1 segmented, with 1 campaniform sensillum (camp) on proximal dorsal surface; without bifurcated setae (bs); with about 14 setae; with 1 rather spur­like tarsal spur (tabs), about 20 m long; tarsal digitules (tdgt) apparently absent or setose. Claws (c) broadly fused to base of tarsus, with no articulation, length 90–95 m; without claw digitules (cdgt). Meso­ and metathoracic legs: lengths (m): coxae (cx) II 222; III 270– 285 m. Metacoxae with a group of 37 small hs near base, and 31 longer setae distally. Trochanter (tr) + femur (fm): II 375; III 460–475 m long; metatrochanter with 37 hs but without a long flagellate seta; trochanter with a group of about 9 campaniform sensilla (camp) on each lateral surface near coxal articulation; metafemur with about 70 hs. Tibia (ti): II 420; III 590 m long; metatibiae with a few spur­like setae along ventral margin, each about 16 m long, plus numerous short setae throughout; bifurcated setae absent; tibial spurs (tibs) undifferentiated. Tarsi (ta) 1 segmented, II 135; III 150–155 m long; with perhaps only 1 campaniform sensillum (camp) on proximal dorsal surface; without bifurcated setae (bs); with 17 setae, of which 3 along ventral margin rather spur­like; tarsal spurs (tabs) undifferentiated but spurs about 18 m long; tarsal digitules (tdgt) undifferentiated but setose. Claws (c) particularly elongate, without a denticle (cd) and not digitate; claw III about 110–113 m long, with 2 rather spinose digitules (cdgt), each about 20–25 m long.

Abdomen

Without caudal extensions. Tergites (at) present medially on all segments; sternites (as) larger, present medially on all segments; small pleurites present on segments II–VIII. Setae: dorsal abdominal setae: segments I–V with 11–21 on each side, segments VI and VII with 11–17 small setae laterally and 16–18 very short setae around tubular ducts (tdc); segment VIII with 8 setae on each side of anus (an); ventral abdominal setae (avs): in 2 media groups and 2 lateral groups on each sternite, with totals of 8–17 on each side, most on segment VIII. Pores absent; segments VI and VII with a median group of 5 and 6 tubular ducts (tdc) respectively; ducts large and sclerotised; each duct about 10–17 m wide, 35–40 m long, largest medially; each with about 2/5th of tube extending above derm surface; each duct with a series of shallow, longitudinal inner ridges; internal apex with numerous small, finger­like projections; each group of tdc with a band of minute setae along anterior margin. Pleural setae divided into dorsal (dps) and ventral pleural setae (vps), latter represented by a small group of 5–11 setae of varying lengths and dorsal group with 4–6 setae on each side; with total of 16 on each pleurite VIII. Long setae entirely absent from abdomen. Abdominal spiracles (asp) without a sclerotised peritreme, but probably with membranous openings on segments I–IV.

Genital segment: anus (an) present just anterior to penial sheath on dorsal surface, width 30 m. Penial sheath (ps) strongly sclerotised and approximately quadrate, but extending to a blunt apex posteriorly; length about 178 m, width 153 m at widest point; most of sclerotised area on posterior half covered in numerous short setae (pss) (each 16–35 m long); posterior apex with many small sensilla (psp). Penial sheath with a ventral slit, whose sides are more membranous than elsewhere. Aedeagus (aed) about 215 m long, broadest posteriorly, probably articulating with a small dense basal rod (bra) on anterior margin ventrally, where ps appears to be bifurcate; emerges through ventral slit posteriorly. Eversible endophallus (eph) present but possibly short.

Comment

The above description agrees closely with that of Jakubski (1965) as far as the latter goes.

Figures

FIGURE 9. Male Heteromargarodes americanus Jakubski. Letters as for Fig. 6.