Asterolecanium petrophilae (Fuller)

Hodgson, Chris, 2020, A review of neococcid scale insects (Hemiptera: Sternorrhyncha: Coccomorpha) based on the morphology of the adult males, Zootaxa 4765 (1), pp. 1-264 : 187-190

Asterolecanium petrophilae (Fuller) ( Fig. 73 )

Planchonia petrophilae Fuller 1897, 1345 . Type data: Australia, West Australia, Swan River, on Petrophila linearis . Syntypes, unknown, by original designation. Type depository: USNM.

Asterolecanium petrophilae (Fuller) ; Fuller 1899, 456. Change of combination.

Material examined. Australia, no collection details, ex George Compere coll, #874, ( USNM): 1/2ad ♂♂ (fair-poor; only just emerged, wings and legs not expanded; most of legs missing; an antenna missing).

Note: because these specimens had only just emerged, it is likely that the sclerotisation of certain structures was not complete and dermal reticulations may not have developed.

Mounted material: very small, total body length 0.62–0.67 mm; robust; antennae a little more than half total body length; exceptionally long seta only noted on antennal segment VII; body with very few setae, fleshy setae (fs) restricted to limbs and difficult to differentiate from hair-like setae (hs); length of antennal setae more than width of antennal segments. Wings not fully expanded.

Head: appearing oval to rather triangular in dorsal view; width across genae 150–155 μm. Median crest (mc) prob- ably broad but limits not visible, not apparently reticulated; with a pair of sclerites posteriorly lying diagonally to midline, representing postoccipital ridge (por); without dorsal head setae (dhs). Mid-cranial ridge: absent both dorsally and ventrally; without reticulations laterally; with 2 pairs of ventral mid-cranial ridge setae (vmcrs). Genae (g) without polygonal reticulations; genal setae (gs) absent; genal protuberance present. Simple eyes: with two pairs of round simple eyes each subequal in size, each 20–22 μm wide. Ocelli (o) absent. Ocular sclerite (ocs) sclerotised but reticulations barely visible. Preocular ridge (procr) not visible dorsally or ventrally. Postocular ridge (pocr) moderately developed, extending dorsally but not close to dorsal eyes and then dorso-posteriorly to level with postoccipital ridges. Dorsal ocular setae (docs) absent. Ventral head setae (vhs): without setae anterior to simple eyes but 1 or 2 pairs between ventral eyes. Preoral ridge (pror) poorly developed. Cranial apophysis (ca) short, triangular and pointed; 12–14 μm long.

Antennae: 9-segmented and filiform; 350 μm long (ratio of total body length to antennal length 1:0.57); hs possi- bly restricted to pedicel and segment III, all other setae fs; extremely long setae only noted on segment VII. Scape (scp): 16–25 μm long, 33–35 μm wide, without setae. Pedicel (pdc): length 25–27 μm, width 23–25 μm; with a few concentric reticulations; with 2 hs. Segments III–IX each 16 μm wide; lengths of segments (μm): III 56, IV 46–50, V 36–42, VI 45–52, VII 33–38, VIII 28–30; hs each 8 μm long, fs each 24–28 μm long; approximate number of setae per segment: III 0 or 1 hs + 3–6 fs (sensilla basiconica not noted); IV 8–13 fs; V 9 or 10 fs; VI 10–16 fs; VII 8–11 fs (bristles (ab), if present, undifferentiated); VIII 6 or 7 fs. Segment IX (apical segment) 38–45 μm long, with 4 or 5 fs, 4 capitate setae (caps), 1 long antennal bristle + 2 short ab; sensilla basiconica (sb) present.

Thorax. Prothorax: pronotal ridge (prnr) and pronotal sclerites (prn) possibly absent (possibly not sclerotised yet?); lateral pronotal (lpns) setae, medial pronotal setae, post-tergites and post-tergital setae absent. Sternum (stn 1) not sclerotised and without ridges or reticulations laterad to median ridge; transverse ridge weak; median ridge strongly sclerotised anteriorly and quite long, extending anteriorly to between procoxae (length about 65 μm long); without prosternal setae (stn 1 s). Anteprosternal (astn 1 s) and antemesospiracular setae (am 2 s) absent. Proepisternum and cervical sclerite poorly developed, not reaching head.

Mesothorax: prescutum (prsc) 58–65 μm long, 90–105 μm wide; striations not visible; prescutual setae (prscs) absent; prescutal ridges (pscr) and prescutal suture (pscs) well developed. Scutum (sct): median membranous area squashed on both specimens but 115 μm wide, bounded laterally by strongly sclerotised margins; scutal setae (scts) probably absent; presence of reticulations uncertain. Scutellum (scl) 115 μm wide, 50 μm long; with a large foramen; without scutellar setae (scls). Basisternum (stn 2) about 115 μm wide, 70–80 μm long; median ridge (mdr) strong poste- riorly but fading anteriorly; bounded anteriorly by a moderately strong marginal ridge (mr) and posteriorly by a strong precoxal ridge (pcr 2); without basisternal setae (stn 2 s); lateropleurite (lpl) reasonably broad, not heavily sclerotised and without an extension from marginal ridge anteriorly; furca (f) well developed, broad basally, arms more or less parallel; extending anteriorly about 3/4 to marginal ridge. Mesopostnotum (pn 2) and postnotal apophysis (pna) well developed; area bounded anteriorly by scutellum and laterally and posteriorly by mesopostnotum weakly reticulated. Mesepisternum (eps 2) not apparently striated; subepisternal ridge (ser) very weak. Postalare (pa) not apparently reticulated anteriorly; without postalare setae (pas). Mesothoracic spiracle (sp 2): peritreme 15–17 μm wide. Postmesospiracular setae (pm 2 s) absent. Tegula (teg): weakly developed, with 4 tegular setae (tegs) on each side.

Metathorax: metatergal setae (mts) and dorsospiracular setae (dss) absent. Dorsal part of metapleural ridge (plr 3) absent; ventral part of metapleural ridge well developed but short; metepisternum (eps 3) unsclerotised, without postmetaspiracular setae (eps 3 s). Metepimeron (epm 3) sclerotised but without setae. Antemetaspiracular setae (am 3 s) absent. Metathoracic spiracle (sp 3): width of peritreme about 15 μm. Metasternum (stn 3) lightly sclerotised. Anterior metasternal setae (amss) and posterior metasternal setae (pmss) absent.

Wings: too crumpled to indicate anything but alar lobe and alar setae considered to be absent. Hamulohalteres absent.

Legs: legs either almost entirely missing or most segments very distorted and all segments probably not fully expanded. Hair-like setae long and therefore difficult to separate from fs. Possible measurements: coxae (cx): I 60; II 55; III 66 μm long; coxa III with 12–14 setae; long apical seta on each coxa about 45 μm long Trochanter (tr) + femur (fm) not measureable; trochanter III elongate and broadest distally, strongly overlapping femur; with about 5 or 6 setae; long trochanter seta about 40 μm long; with 2 campaniform sensilla on either side; femur III with 6 or 7 setae. Tibia (ti) not measureable, tibia III with a total of about 18 or 19 setae, becoming spur-like on distal third; without apical spurs (tibs). Tarsi (ta) perhaps: I 110; II 95; III 90 μm long; tarsus III with 19–25 setae, mainly spur-like, particularly distally; tarsal spurs undifferentiated; tarsal campaniform pore present; tarsal digitules (tdt) fine, with small apical knobs, significantly longer than claw. Claws (c) quite long and narrow, rather longer than width of tarsi, slightly curved, without a denticle, not held at right-angles to tarsus; III 18–19 μm long; claw digitules (cdt) fine, with small apical knobs, longer than claw.

Abdomen: segments I–VII: tergites (at) and sternites (as) not apparently sclerotised or reticulated. Caudal extension (ce) of segment VII absent. Dorsal abdominal setae (ads) absent. Pleural setae: dorsopleural setae (dps): III–VII each with 1 hs on each side; ventropleural setae (vps) absent. Ventral abdominal setae (avs) (totals): II–IV setae absent; V–VII each with 1 pair hs.

Segment VIII: tergite and sternite probably sclerotised; tergite and sternite without setae; caudal extension (ce) rounded and ill-defined, with 3 pleural setae on each side, one 16–25 μm long, others much shorter. Glandular pouches (gp) absent.

Genital segments: length of penial sheath (style + IX) 132–150 μm (ratio of total body length to penial sheath length 1:0.11), length of style 88–107 μm. Segment IX quite broad, 15–18 μm long, 60–65 μm wide; sides parallel; anus not detected. Style broad anteriorly (60 μm wide), rapidly narrowing to about 17 μm wide and then more or less with parallel margins to apex; with 1 or 2 pairs of longer setae ventrally laterad to basal rod (each 16–20 μm long), plus 0 or 1 pairs of smaller setae dorsally (each 2–9 μm long); margins of style each with 3 or 4 pairs of short setae, each about 5 μm long; small sensilla present on apex. Basal membranous area (bma) present anterior to and on either side of basal rod; basal rod (bra) 18–23 μm long, not extending down aedeagus.Aedeagus (aed) long and broad, almost parallel sided, 95–100 μm long (ratio of length of aedeagus to length of basal rod 1:0.25), extending to apex of penial sheath.

Comment. Of the known adult male asterolecaniids, A. petrophylae has 9-segmented rather than 10-segmented antennae (as has Asterodiaspis alba ). However, male A. petrophylae appear to lack ventral head setae, have a very differently-shaped penial sheath and a much broader aedeagus.

Figures

FIGURE 73. Asterolecanium petrophilae (Fuller). Macropterous male. (Asterolecaniidae).