Physokermes, Targioni Tozzetti, 1868

Kozár, Ferenc, Gounari, Sofia, Hodgson, Chris & Fetyk, Kinga, 2012, A new species of Physokermes Targioni Tozzetti (Hemiptera: Coccoidea: Coccidae) from Greece, Zootaxa 3566, pp. 23-38 : 24-25

PHYSOKERMES Targioni Tozzetti, 1868

Type species: Coccus hemicryphus Dalman, 1826

Generic diagnosis. Unmounted adult female. Pre-reproductive adult membranous and reddish-brown. Postreproductive female globular or kidney–shaped, often longer than wide; old females, light to dark brown, derm becoming heavily sclerotized when mature.

Mounted adult female. Body usually broadly oval, young specimens membranous, becoming sclerotized at maturity; normally with a heavily sclerotized median area (or cauda) dorsad to anal opening. Anal plates absent. Venter. Antennae developed in Nearctic species, but reduced, often tubercle-like, in Palaearctic species, with 1–3 indistinct segments. Labium one segmented, with 4 pairs of setae. Stylet loop as long as body. Legs reduced, often to 2 or 3 segmented stubs or plates. Multilocular disc pores mainly with 10 loculi, numerous, mainly in groups or in 2 submedial longitudinal and several transverse bands on mid-venter and on dorsum of anal lobes in the new species described below. Tubular ducts of two sizes present (only one size on P. hellenicus ); microducts few, either present anteriorly on head or absent. Setae usually few, short, but with 1 or 2 pairs of longer interantennal setae.

Margin. Not demarcated; stigmatic and marginal setae absent. Eyespot probably marking margin.

Dorsum. Setae mostly short, cylindrical, clavate or pointed, scattered over surface. Simple pores, tubular ducts and microducts scattered over most of derm. Multilocular disc pores present on one species. Anal ring reduced to a small narrow sclerotised ring, without pores but with 0–6 short setae; derm surrounding anal area and along margins of anal lobes becoming heavily sclerotized with age. Anal lobes with a group of long hair-like setae.

First-instar nymphs. Present on leaves. Antennae and legs well developed; antennae six segmented. Anal plates triangular. Stigmatic clefts each with 2 stigmatic setae present in some Palaearctic species but setae absent in other species.

Distribution. Physokermes is restricted to the Holarctic and currently contains 11 species (12 with the new species described below), of which seven (eight) appear to be endemic to the Palaearctic ( Fig. 1 ) ( Borchsenius, 1957; Danzig, 1980) and four to the Nearctic ( Kozár & Ben-Dov, 1997).

Most of the eight endemic Palaearctic species live in the southern zone on isolated mountains at high elevation. This distribution could be the result of isolation of species on different host plants and on different mountains by past ice ages, as mentioned by Danzig (1972), Sugonjaev (1984) and Sugonjaev and Voinovich (2006). Only the Holarctic species P. hemicryphus and the western Palaearctic species P. piceae are distributed widely in the Palaearctic Region, where they are found on a wide range of host plants. However, it is possible that these two species names might include several cryptic species. The appearance of isolated species on high mountains suggests that more undescribed Physokermes species might be present in similar habitats in Italy, France, Spain and North Africa.

Figures

FIGURE 1. Distribution of the Physokermes species in the Palaearctic Region. P. hemicryphus is widely distributed throughout the region; Ph. piceae is present only in the European part.