Aclerda, Signoret, 1874

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: 211-213

publication ID 10.11646/zootaxa.4765.1.1

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Aclerda   sp. A ( Fig. 82 View FIGURE 82 )

Material examined. Mexico, 5 miles west of Ciudad Hildago, Michoacán, on grass ( Poaceae   ), 7.iii.1972, D.R. Miller & F.D. Parker #2214 ( USNM): 1/2 ad ♂♂ (one in good condition, the other missing the posterior part of the abdomen, and both missing some legs and bits of antennae).

Mounted material: total body length 1.47 mm; width across triangular plates 0.29–0.30 mm; slender. With small convex pores (cp) on thorax and abdomen.

Head: approximately diamond-shaped in dorsal view; length 185 μm; width across genae 215 μm. Median crest

(mc) not reticulated; with 1 hs dorsal head seta (dhs) on each side anteriorly and another pair posteriorly. Dorsal mid-cranial ridge absent; ventral mid-cranial ridge (vmcr) represented by a very short ridge between scapes only; vmcr with a narrow, slightly reticulated border and a broader area of slight sclerotisation immediately posterior to each scape, which extends posteriorly to ocular sclerite; without ventral mid-cranial ridge setae (vmcrs). Genae: genal setae (gs): 1 hs posterior to each dorsal eye. Eyes: two pairs of round simple eyes, subequal in size (24–31 μm wide). Ocelli (o) present laterally. Ocular sclerite (ocs): each polygonal reticulation without inner microridges. Preocular ridge (procr) very short immediately posterior to each scape. Postocular ridge (pocr) very short, perhaps only extending about half-way to ocelli and not heavily sclerotised. Dorsal ocular setae (docs) absent. Ventral head setae (vhs): 4 hs in a group just posterior to each scape. Cranial apophysis (ca) 94–121 μm anterior to tentorial bridge; with numerous short branches apically.

Antennae: total length 837 μm long (ratio of total body length to antennal length 1:0.57). Scape (scp): 46–50 μm long, 44–47 μm wide, with 1 hs on ventral surface and 2 hs on dorsal surface. Pedicel (pdc): length 38–40 μm, width 38–42 μm; with 1 fs + 1 hs (no sensilla placodeum detected). Segments III–X all 16–21 μm wide; fs each 23–28 μm long; lengths of segments (μm): III 99–106; IV 130–135; V 120–124; VI 106–124; VII 102–104; VIII 89–91 and IX 69–71; setae rather few, approximate number per segment: III 1–3 fs + 1–3 hs + 1 or 2 sensilla basiconica; IV 13–15 fs + 0 or 1 hs; V 9–15 fs + 0 hs; VI 10 or 11 fs + 0 hs; VII 15 fs + 0 hs; VIII 8 fs + 0 hs; IX 12 fs + 0 hs. Segment X 60–62 μm long, with 7 fs + 3 capitate setae; antennal bristles not differentiated.

Thorax. Prothorax: pronotal ridge (prnr) well-developed and probably fusing medially; lateral pronotal sclerite (prn) slight and narrow. Medial pronotal setae, post-tergites and post-tergital setae absent. Small convex pores (cp) present as follows: a group laterad to each pronotal sclerite, a group near outer margin and 0–2 posteriorly, total 9–15 on each side. Sternum (stn 1) sclerotised, but without either a median or transverse ridge; without reticulations. Anteprosternal (astn 1 s) and antemesospiracular setae (am 2 s) absent

Mesothorax: prescutum (prsc) 163–171 μm wide, 93–109 μm long; prescutal ridges (pscr) and prescutal suture (pscs) well developed; prescutal setae absent. Scutum (sct): median membranous area 111–124 μm wide, 15–31 μm long; scutal setae (scts): 0 or 1 hs on each side; bounded laterally by a weakly sclerotised margin; reticulations weak or absent laterad to scutellum. Scutellum (scl) 155–157 μm wide, 46–48 μm long; with a moderately large foramen; without scutellar setae. Basisternum (stn 2) 192–202 μm wide, 124–131 μm long; median ridge (mdr) very weak or absent; bounded anteriorly by a weak marginal ridge (mr) and posteriorly by a strong precoxal ridge (pcr 2); without basisternal setae (stn 2 s); lateropleurite (lpl) very broad, without an extension along anterior margin; furca (f) well developed, broad basally, arms more or less parallel and quite short. Area bounded anteriorly by scutellum and laterally and posteriorly by mesopostnotum lightly sclerotised, with a narrow membranous area along anterior and lateral margins. Mesepisternum (eps 2) and subepisternal ridge (ser) well developed. Postalare (pa) not reticulated anteriorly; without postalare setae (pas). Postmesospiracular setae (pm 2 s) absent. Mesothoracic spiracle (sp 2): peritreme 23–28 μm wide, each with 1–4 disc-pores. Tegula (teg) with 0–5 hs tegular setae (tegs).

Metathorax: with 1 pair metatergal setae (mts) and 4–7 small convex pore laterally. Dorsospiracular setae (dss) absent. Dorsal part of metapleural ridge (plr 3) absent; ventral part of metapleural ridge not well developed; metepisternum (eps 3) represented by a small area of sclerotisation near metapleural ridge; with 7–10 hs postmetaspiracular setae (eps 3 s) on each side. Metepimeron (epm 3) sclerotised, without setae. Antemetaspiracular setae (am 3 s) absent. Metathoracic spiracle (sp 3): width of peritreme 24–27 μm, with 2 disc-pores. Postnotal apophysis (pna) represented by a narrow, reticulated slit between meso- (pn 2) and metapostnotum (pn 3). Metasternum (stn 3) lightly sclerotised. Anterior (amss) and posterior metasternal setae (pmss) absent.

Wings: very narrow, about 1.1 mm long and 0.3 mm wide (ratio of length to width 1:0.27; ratio of total body length to wing length 1:0.78); without alar lobes and alar setae. Hamulohalteres absent.

Legs: legs subequal in length. Coxae (cx): I 89–100; II 77–93; III 93–100 μm long; coxa III with 6–9 hs (2 long, each 52–78 μm long). Trochanter (tr) + femur (fm): I 195–196; II 204–227; III 186–208 μm long; trochanter III with 3 hs; long trochanter seta short, each 21–39 μm long, flagellate; femur III with 5–8 fs + 11–23 hs. Tibia (ti): I 248; II 257–279; III 232–239 μm; tibia III with a total of 38–40 setae, mostly spur-like, particularly on distal third of leg; tibio-tarsal articulatory sclerosis absent; apical spur (tibs): length ( III) 15–21 μm. Tarsi (ta): I 130; II 120–127; III 111–115 μm long (ratio of length of tibia III to tarsus III 1:0.49); tarsus III with 18–25 setae, mostly spur-like; tarsal spurs (tabs) absent or barely differentiated; tarsal digitules capitate. Claws (c): ( III) 26 μm long, without a denticle and with capitate digitules.

Abdomen: tergites (at) and sternites (as) sclerotised on all segments; pleurites (ap) sclerotised only on segments III–VII, each extending ventrally to include ventral pleural setae. Dorsal abdominal setae (ads) (on each side): seg- ments I–VII each with 1 hs + 1–4 convex pores (cp). Pleural setae (on each side): dorsopleural setae (dps): II & III both with 0 or 1 hs + 3–6 cp; IV–VII each with 2–5 hs + 1–3 cp; ventropleural setae (vps) II 0 hs; III–VII each with 1 hs. Ventral abdominal setae (avs) (totals): II 0 hs; III & IV both with 2 hs; V–VII each with 4 hs. Caudal extensions on segment VII absent.

Segment VIII: sternite forming a sclerotised plate, with a strongly sclerotised lateral margin; without a caudal extention but with 3 or 4 hs longer pleural setae, one of them 77+ μm long. Glandular pouches absent.

Genital segments: penial sheath (ps) articulating anteriorly with sternite of segment VIII; penial sheath (ps) 206 μm long including sclerotised part of segment VIII (ratio of total body length to penial sheath length 1:0.14); segment IX 69–82 μm wide at swollen base. Anus (an) surrounded by a sclerotised ring. Style rather parallel-sided and then narrowing to a blunt apex. Basal rod (bra) perhaps 27–51 μm long, appearing to fuse with aedeagus. Aedeagus (aed) short, possibly 37–57 μm long (ratio of aedeagus length to basal rod length about 1:0.83); approxi- mately parallel-sided but wider than apex of style. Membranous ‘endophallus’ present. Style with either very small setae or sensilla over most of surface.

Comment. The adult male of Aclerda   sp. A. differs from that of A. arundinariae   in having: (i) small convex pores on the dorsum of the thorax and abdomen; (ii) a small metepimeron; (iii) the abdominal pleurites extending ventrally to include the ventral pleural setae, and in (iv) the apparent fusion of the basal rod and the aedeagus. In possessing most of these characters, it is very similar to Aclerda   sp. B, but the latter has: (i) a rather narrower mesothorax (the basisternum is much smaller) and also (ii) lacks postmetaspiracular setae and (iii) a metepimeron.


Smithsonian Institution, National Museum of Natural History