Orbuspedum, Gavrilov-Zimin, 2017

Gavrilov-Zimin, I. A., 2017, A remarkable example of symbiosis between an animal and a fungus in a new species of legless mealybug (Insecta: Pseudococcidae), Journal of Natural History 51 (37 - 38), pp. 2211-2224 : 2213

Orbuspedum gen. nov.

Type species Orbuspedum machinator sp. nov., here designated.

Description

Adult female. Body spindle-form, with posterior segments of abdomen heavily sclerotized. Antennae each 2-segmented. Legs entirely absent. Anal apparatus simplified, without setae. Vulva of unusual structure, funnel-shaped, directed anteriorly. Anterior and posterior pairs of ostioles absent. Small oval circulus present. Multilocular pores absent. Trilocular pores and simple discoidal pores scattered through entire body surface, except for posterior abdominal segments where they are completely absent. Discoidal pores of irregular structure or duct-like pores absent. Tubular ducts each with very deep collar present on posterior abdominal segments only. Dorsal surface of body covered with small, thin conical setae and minute flagellate setae; ventral surface covered by longer flagellate setae; posterior abdominal segments densely covered by significantly longer flagellate setae on both surfaces. Sacciform invaginations of sclerotized cuticle of different sizes present in transverse rows across most body segments.

Diagnosis

The new genus differs from all other genera of legless mealybugs in having an anteriorly directed vulva. In other characters, Orbuspedum gen. nov. seems to be similar to the large, widely distributed genus Antonina Signoret , but differs from the latter in the total absence of multilocular and irregular disc pores (wax glands); see modern identification keys to genera of legless mealybugs in Hendricks and Kosztarab (1999) and Danzig and Gavrilov-Zimin (2015).

Additionally, the new monotypic genus differs from all other known scale insect genera ecologically, in the peculiar mode of life of females and female larvae inside individual fungal domiciles (see ‘Mode of life’ section under the species description).

Etymology

The generic name is constructed from appropriate Latin words, and means ‘legless’. Gender masculine.