Cryptostigma silveirai (Hempel)

Kondo, Takumasa, 2010, Taxonomic revision of the myrmecophilous, meliponiphilous and rhizophilous soft scale genus Cryptostigma Ferris (Hemiptera: Coccoidea: Coccidae) 2709, Zootaxa 2709, pp. 1-72 : 58-62

Cryptostigma silveirai (Hempel)

( Figs 24 & 25)

Lecanium silveirai Hempel ; Hempel, 1900a: 5.

Neolecanium silveirai (Hempel) ; Cockerell, 1902a: 143; 1902b: 451; 1902c: 254; Hempel 1900b: 424; Fernald 1903: 177; Costa Lima 1924: 135; Lepage & Piza 1941: 21; Vernalha 1953: 139.

Cryptostigma silveirai (Hempel) ; Kondo & Williams, 2002: 127. Change of combination.

Type material examined. Lectotype, here designated. Lecanium silveirai Hempel , adult ♀. BRAZIL: 359 Type 45, No. 95.069, 1 slide with 1 specimen (original slide with 4 specimens, remounted onto 4 slides with 1 specimen on each, lectotype # 1/4)( MZSP).

Paralectotypes. Same data as lectotype, 3 (3): each slide labelled # 2/4, 3/4, 4/4 ( MZSP) ; Lecanium silveirai Hempel , BRAZIL: Minas [Gerais], São Joãn del Rei, 15.v.1899, coll. A. Silveira, slide-mounted from MZSP Type dry material No. 95.069, ex videira (grape), AL-201-99, 2 (2) ( MZSP) , 2 (2) ( AUCC); Mesolecanium silveirai Hempel, No data, 11 (11: 10 adult ♀ + 1 first-instar nymph) ( MZSP) .

Adult female ( Fig. 24)

Unmounted material. Female subcircular or slightly elliptical, light red. Dorsum convex, 5.0–6.0 mm long, 4.0–5.0 mm wide, and 2.5–3.0 mm tall; lustrous, with a hard derm, covered by a thin layer of waxy secretion; with a median, longitudinal sulcus; derm around anal plates sunken. Anal cleft 0.6 mm. in length; anal lobes contiguous. With 2 lines of white powdery secretion on both sides (probably referring to the wax on the spiracular furrows secreted by the spiracular disc-pores). When the insect is removed from its resting site, it leaves a circular stain of white wax (Translated from Lepage & Piza, 1941).

Mounted material. Body outline oval, 3.0– 4.8 mm long, 2.7–3.5 mm wide (n=19).

Dorsum. Derm membranous, with numerous circular sclerotic pores scattered evenly on dorsum; each pore 15–23 µm wide. Dorsal body setae each 9–13 µm long and sharply spinose, setal sockets normal, thick but most setae present on a sclerotized plate 15–34 µm wide; present evenly on dorsum. Simple pores not detected. Dorsal microducts bilocular, each about 3–4 µm wide, numerous, evenly distributed on dorsum. Preopercular pores absent. Sclerotic area present around anal plates. Anal plates together quadrate, with rounded angles, each plate 183–243 µm long, 92–108 µm wide, anterolateral margin 135–173 µm long, posterolateral margin 113–135 µm long; with 5 setae on dorsal surface, plus 1 ventral subapical setae on each plate; plates located about 1/5 of body length from posterior margin. Anal ring with 10 setae. Eyes absent.

Margin. Margin smooth. Marginal setae not differentiated from dorsal setae. Stigmatic clefts very deep; stigmatic sclerotization enclosing spiracles; stigmatic setae not detected.

Venter. Derm membranous. Ventral setae slender, each 13–23 µm long, those on abdominal segments usually longer. Ventral microducts each about 2 µm wide scattered evenly on venter. Tubular ducts absent. Clypeolabral shield 372–458 µm wide. Multilocular disc-pores each 5–8 µm wide with 5–8 (mostly 7) loculi, abundant around vulva, and mid-ventrally on all abdominal segments, with a few extending as far as mesothorax. Spiracular disc-pores each 5–7 µm wide with 3–7 (mostly 5) loculi, present between each spiracle and body margin, plus a group extending inwards from each posterior spiracles inwards to near each mesothoracic leg. Antennae very small, 1 segmented, total length 26–47 µm, represented by a flattened segment bearing numerous fleshy and flagellate setae. Interantennal setae about 3 pairs. Legs greatly reduced, represented by a small sclerotic plate associated with several setae; length 11–26 µm. Spiracles larger than legs, located near margin; each anterior peritreme 124–162 µm wide, each posterior peritreme 135–189 µm wide.

Diagnosis. The adult female of C. silveirai can be diagnosed by the following features: (i) sclerotic pores present, (ii) dorsal setae sharply or bluntly spinose, each mostly on a sclerotized plate, but a few with normal or well-developed setal sockets, (iii) preopercular pores absent, (iv) each anal plate with about 5 setae on dorsal surface, (v) marginal setae not differentiated from dorsal setae, (vi) antennae 1 segmented, reduced to a small round plate bearing numerous setae, (vii) legs greatly reduced, represented by a small sclerotic plate with several setae, (viii) with a group of spiracular disc-pores extending from each posterior spiracle inwards to near each mesothoracic leg, and (ix) ventral tubular ducts absent. C. silveirai appears closest to C. longinoi and C. rhizohilum , but it can be easily differentiated from the former by the absence of ventral simple pores, and from the latter by the absence of a subcircular group of simple pores next to each stigmatic sclerotization.

Remarks. In Hempel’s (1900a) original description of C. silveirai ( Lecanium silveirai ), he reported the species as causing serious damage by feeding on the roots of grape vines in the localities of Sete Lagoas and Diamantina, in the State of Minas Gerais, Brazil. Lepage and Piza (1941) later redescribed the species, as Neolecanium silveirai , and reported it as a serious pest of grape vines in Araraquara, in the State of San Paulo. Lepage and Piza (1941) conducted chemical trial experiments on the insects, which occur underground in the roots of grape and are found up to a depth of 90 cm, thus making them difficult to control.

First-instar nymph ( Fig. 25)

Unmounted material. Nymphs small, active, rose-coloured, elliptical, with well-developed legs and antennae (Translated from Lepage and Piza, 1941).

Mounted material. Elongate oval, 706–792 µm long, 501–555 µm wide (n=1).

Dorsum. Dorsal derm membranous. Dorsal setae each 8–11 µm long and slender, totalling about 13 pairs in 2 mid-dorsal longitudinal rows, extending from head region towards area just anterior to anal plates. Trilocular pore present on each side of head near margin. Dorsal microducts each about 2 µm wide, appearing bilocular, numerous. Simple pores each about 3.5 µm wide, numerous. Anal plates together quadrate, each plate 100 µm long, 45 µm wide; dorsal surface with 1 seta present on mid-area of plate, plus 3 apical setae; ventral surface with 1 fringe seta. Anal ring as in generic diagnosis.

Margin. Outline smooth. Marginal setae each 18–22 µm long and sharply spinose, totalling more than 90, with about 10 between each group of anterior and posterior stigmatic setae. Stigmatic setae each 12–18 µm long and bluntly spinose; with 3 anterior stigmatic setae and 4 posterior setae. Eyespots hard to detect, present on margin on area anterior to antennal scape.

Venter. Ventral derm membranous. Antennae 5 segmented, total length 334 µm. Mid-ventral setae slender,

1 pair present on last 3 abdominal segments. Interantennal setae 1 pair. Ventral submarginal setae flagellate, with 7 pairs of setae on abdomen between each posterior stigmatic area and anal cleft; in addition to the 7 pairs of setae there are 3 setae just below each posterior stigmatic furrow; also with about 20 setae between anterior and posterior stigmatic areas, about 7 on each side between eyes and anterior stigmatic areas, and 2 pairs of slender setae on head region. Ventral microducts each about 2 µm wide, about 16 anteriorly between anterior stigmatic areas, about 9 on each submarginal area between anterior and posterior stigmatic setae; also with a group of about 9 present between each prothoracic and mesothoracic legs, and 12 between posterior stigmatic area and anal cleft: 2 microducts per each pair of submarginal setae except for the last pair at the anal cleft. Spiracular disc-pores each about 4 µm wide with 3–6 (mostly 5) loculi, each anterior stigmatic furrow with about 12 pores, posterior furrow with about 15 pores. Spiracular peritremes each 22–24 µm wide. Clypeolabral shield 196 µm wide. Legs well developed, with numerous setae, trochanter + femur 179–185 µm long, tibia + tarsus 221–232 µm long; microctenidia present on apex of tibia. Prothoracic tarsal digitules dissimilar, 1 knobbed and 1 spiniform; meso- and metathoracic tarsal digitules similar, knobbed. Claw with a small denticle; claw digitules both slender, knobbed.

Diagnosis. The first-instar nymph of C. silveirai can be diagnosed by the combination of the following features: (i) dorsal setae present in 2 longitudinal rows of about 13 setae, (ii) each anterior stigmatic cleft with 3 stigmatic setae; each posterior cleft with 4 setae, (iii) with about 10 marginal setae between anterior and posterior stigmatic setae, (iv) antennae 5 segmented, (v) with pairs of submedian abdominal setae on last 3 abdominal segments, (vi) each anterior stigmatic furrow with about 12 pores; each posterior furrow with about 15 pores, (vii) with a group of microducts between pro- and mesothoracic coxae on each side of body, and (viii) legs with many setae. C. silveirai is the only species in the genus with first-instar nymphs that have 2 pairs of ventral submarginal setae on the head region.

Host plants. Vitaceae : Vitis vinifera .

Associated Hymenoptera . None reported.

Males. Lepage and Piza (1941) described the male test of C. silveirai (as Neolecanium silveirai ) as glazed satin-like, 2 mm long, 1 mm wide, 1 mm tall, of elliptical form, divided by clear lines into 3 symmetric areas. Lepage and Piza (1941) described the adult male as typical of males in the genus ( Neolecanium Parrott ).

Distribution. Neotropical Region: Brazil (Minas Gerais, São Paulo).