Rhizoecus albidus Goux

Moghaddam, Masumeh, 2013, A review of the mealybugs (Hemiptera: Coccoidea: Pseudococcidae, Putoidae and Rhizoecidae) of Iran, with descriptions of four new species and three new records for the Iranian fauna, Zootaxa 3632 (1), pp. 1-107 : 96-98

Rhizoecus albidus Goux

( Fig. 54 )

Rhizoecus (Pararhizoecus) albidus Goux, 1942: 40 . Rhizoecus uniporus Borchsenius & Tereznikova, 1959: 323 . Rhizoecus gentianae Panis, 1968: 550 .

DIAGNOSIS. A very small elongate-oval species. Posterior end of body rounded. Anal lobes poorly developed, each with 1 long ventral seta and 2 long dorsal setae, appearing as a group of 3. Antennae 6-segmented, geniculate. Both pairs of ostioles well developed. Circulus present within borders of segment IV, heavily sclerotized and cone shaped with distal circular plate containing about 7 circular areas. Dorsal surface with numerous short, pointed setae and forming distinct groups on thorax and head; ventral surface with a more or less quadrate sclerotized area containing 4 marginal setae just anterior to clypeus; other body setae short and slender. Trilocular pores scattered on dorsum and venter. Dorsal tritubular pores not numerous, rarely more than 3 on abdominal segments and thorax, and sometimes only a single one on midline but tending to be scattered on head. Ventral tritubular pores very few, usually with a single marginal pore on some of posterior abdominal segments, plus occasional pores on thorax and between antennal bases. Some very minute ducts present on abdominal segments, these very simple and heavily sclerotized, entirely absent from some segments but others with up to 6; ventral ducts similar to those on dorsum, with 2–6 arranged across some posterior abodominal segments.

DISTRIBUTION. Palaearctic. Armenia, Crete, France, Germany, Hungary, Iran, Italy, Kazakhstan, Romania, Russia, Sweden and Ukraine. In Iran, R. albidus occurs in Esfahan, Markazi and Tehran. This mealybug is known from 6 host plant families worldwide (Ben-Dov et al., 2012).

MATERIAL EXAMINED: Esfahan: Esfahan, 4 adult Ƥ, on Festuca arundinacea (Poaceae) , 29.i.2002 (B. Hatami). Markazi: Mahalat, 2 adult Ƥ, on Gymnocalycium sp. ( Cactaceae ), 16.x.1993 (Hosieninia). Tehran: Shahriyar, 4 adult Ƥ, on Echeveria sp. ( Crassulaceae ), 4.v.2000.

COMMENTS. R. albidus occurs on the roots of ornamental plants. The plant families Cactaceae and Crassulaceae are recorded here for the first time.

The accompanying illustration first appeared in Williams (1962) and is used here with permission from the author and the Keeper of Entomology, The Natural History Museum, London.

Figures

FIGURE 54. Adult female Rhizoecus albidus Goux