Pseudococcus viburni (Signoret)

MOGHADDAM, MASUMEH & WATSON, GILLIAN W., 2022, The Scale Insects Of Iran (Hemiptera: Coccomorpha) Part 2 The Mealybugs (Pseudococcidae And Rhizoecidae) And Putoidae, Zootaxa 5126 (1), pp. 1-169 : 118-119

Pseudococcus viburni (Signoret)

( Fig. 53 , Plate 3 H , distribution map Fig. 70 D )

Dactylopius viburni Signoret, 1875a: 323 . Dactylopius indicus Signoret, 1875a: 317 . Dactylopius affinis Maskell, 1894: 90 . Pseudococcus obscurus Essig, 1909: 43 . Pseudococcus capensis Brain, 1912: 182 . Pseudococcus nicotianae Leonardi, 1913: 76 . Pseudococcus longispinus latipes Green, 1917: 264 . Pseudococcus capensis Joubert, 1928: 209 . Pseudococcus fathyi Bodenheimer, 1944: 90 .

Field characteristics: Live adult female 2.5‒5.0 mm long, fairly flattened ovoid, body contents pinkish but surface coated with white mealy wax; margins with 17 pairs of projecting, slender white wax filaments, 1 or 2 pairs of marginal filaments at rear end longest. At maturity, an ovisac of white wax filaments is produced below and behind abdomen, into which yellow eggs are laid. When disturbed, the ostiolar fluid released is colourless (whereas in the similar species P. maritimus (Erhorn) (not recorded in Iran) it is pink or red).

Microscopic diagnosis: Slide-mounted adult female oval. Anal lobes well developed. Antennae each with 8 segments. Legs well developed; hind leg with translucent pores numerous on dorsal surfaces of femur and tibia but absent from hind coxa. Cerarii numbering 17 pairs, each normally with 2 enlarged conical setae; but anterior mesothoracic pair (C 6) and frontal cerarii (C 1) each usually with 3 conical setae. Circulus present, divided by an intersegmental line. Ostioles well developed.

Dorsum with setae mostly short. Trilocular pores evenly distributed. Discoidal pores minute, sparse. Oral rim ducts often each with 2 discoidal pores next to rim, present singly behind each frontal cerarius, normally between cerarii C 6 and C 7, and on abdomen near cerarii C 11 and C 13–-16; other oral rim ducts present on thorax and anterior abdominal segments, and near midline of posterior abdominal segments. Oral collar tubular ducts present on margins of abdominal segments III–VII.

Venter with normal flagellate setae. Multilocular disc pores present posterior to vulva and at anterior and posterior edges of abdominal segments V – VII, not reaching to margins; others located at posterior edge of segment IV; sometimes 1 or 2 present medially on thorax. Discoidal pores minute, sparse; 1–3 pores present adjacent to each eye on membranous cuticle. Oral rim ducts usually present on margins of thorax and abdominal segment I. Oral collar ducts normally of 2 sizes: larger type present across segments III – VII, in groups around abdominal margins and sparse on anterior margin; and minute, slender ducts present medially across abdominal segments and some medially on thorax. Ventral margin opposite metacoxa usually with fewer than 4 small oral collar ducts on each side .

Distribution: Pseudococcus viburni is known from 58 countries in all biogeographical Regions including Iran ( García Morales et al. 2016), where it has been recorded from Elborz, Esfahan, Gilan, Khorasan -e Razavi, Khouzestan, Mazandaran and Tehran provinces ( Moghaddam 2013b).

Host-plants: The mealybug has been recorded on host-plants in 256 genera belonging to 90 families ( García Morales et al. 2016). In Iran, it has been found on: Amaranthaceae : Amaranthus blitum ; Araceae : Dieffenbachia sp. ; Arecaceae : Phoenix sp. ; Bignoniaceae : Catalpa speciose ; Buxaceae : Buxus hyrcana ; Convolvulaceae : Convolvulus mauritanicus ; Cupressaceae : Cupressus sp. , Platycladus orientalis ; Euphorbiaceae : Acalypha sp. and Codiaeum variegatum ; Fabaceae : Albizia sp. , Cercis siliquastrum ; Ginkgoaceae : Ginko biloba ; Lythraceae : Punica granatum ; Moraceae : Ficus carica and Morus alba ; Pinaceae : Pinus sp. ; Rosaceae : Prunus cerasus and Rosa sp. ; Solanaceae : Solanum tuberosum ; Theaceae : Camellia sinensis ; and Vitaceae : Vitis sp. ( Moghaddam 2013b) .

Economic importance: Pseudococcus viburni has been recorded as the dominant mealybug species in the tea gardens of Mazandaran and Gilan provinces in the North of Iran ( Abbasipour & Taghavi 2007) .

Natural enemies: With the farmers’ participation, there has been mass rearing and release of Cryptolaemus montrouzieri Mulsant ( Coleoptera : Coccinellidae ) for biological control of Pseudococcus viburni in tea orchards in Iran ( Malkeshi et al. 2010).

Comments: For a long time, P. viburni was misidentified as P. maritimus in Iran; Heidari (1986) was the first Iranian taxonomist to use the correct name. The species differ as follows (character states of P. maritimus in brackets): (i) hind tibia inflated, with curved sides (parallel-sided); (ii) without a dorsal oral rim duct between C 2 and anterior ostiole (duct usually present); (iii) venter of abdominal segment III usually without multilocular pores (a few pores usually present); (iv) ventral margin between C 9 and C 11 [opposite metacoxa] with fewer than 4 oral collar ducts (more than 4 ducts usually present); and ostiolar fluid in life colourless (pink or red).

Genus RHODANIA Goux

Rhodania Goux 1935: 291 . Type species: Rhodania porifera Goux by original designation.

Principal characters: Body of adult female circular to elongate oval. Antennae each with 6 or 7 segments. Anal lobes poorly developed. Legs small for size of body; claw without a denticle. Cerarii absent. Circulus absent. Posterior ostioles always absent; anterior ostioles usually absent. Multilocular disc pores absent. Quinquelocular pores numerous on both body surfaces. Trilocular pores absent. Oral collar tubular ducts short, present on both body surfaces.

Comments: Worldwide, six species are included in Rhodania ( García Morales et al. 2016) ; one species is known from Iran ( Williams & Moghaddam 2007).

Figures

PLATE 3.A. Pseudococcus viburni (Signoret); B. Trabutina crassispinosa Borchsenius; C. Trabutina mannipara (Hemprich & Ehrenberg); D. Trabutina serpentina (Green); E. Vryburgia amaryllidis (Bouché); F. V. amaryllidis damage on Amaryllis sp. (Amaryllidaceae).

FIGURE 53. Adult female of Pseudococcus viburni (Signoret).

FIGURE 70. Maps of species distributions in Iran. A. Planococcus vovae (Nasonov); B. Pseudococcus comstocki (Kuwana); C. Pseudococcus longispinus (Targioni Tozzetti); D. Pseudococcus viburni (Signoret); E. Rhodania aeluropi Williams & Moghaddam; F. Saccharicoccus sacchari (Cockerell); G. Spilococcus alhagii (Hall); H. Spilococcus mirzayansi (Moghaddam); I. Spilococcus williamsi sp. n.; J. Trabutina crassispinosa Borchsenius; K. Trabutina mannipara (Hemprich & Ehrenberg); L. Trabutina serpentina (Green).