Bemisia, Quaintance & Baker

Martin, Jon H., 2005, Whiteflies of Belize (Hemiptera: Aleyrodidae) Part 2 - a review of the subfamily Aleyrodinae Westwood, Zootaxa 1098 (1), pp. 1-116 : 32-33

BEMISIA Quaintance & Baker

Bemisia Quaintance & Baker, 1914: 99–100 . Type species Aleurodes inconspicua Quaintance, 1900: 28–29 , by original designation. [synonymised with Aleurodes tabaci Gennadius, 1889: 1–3 by Russell, 1957: 122.]

DIAGNOSIS AND COMMENTS. As interpreted here, Bemisia comprises species with puparia ( Figs 24 , 25–27 , 109) which display the following combination of characters:

cuticle usually completely pale, occasionally with brownish pigmentation; margin irregularly crenulate, often modified at caudal and/or thoracic tracheal openings at margin to form ill­defined combs of fine teeth, with margin often shallowly emarginate at these points; transverse moulting sutures not reaching margin; vasiform orifice acute­triangular, sometimes laterally emarginate, usually leading into a pronounced caudal furrow; operculum occupying basal half of orifice; head of lingula typically elongate­triangular, finely spinulose, bearing a pair of stout apical setae ( Fig. 27 , expanded detail), lingula always exposed but included within confines of vasiform orifice; chaetotaxy and presence of dorsal sculpturing and tubercles may be highly variable within species, depending on physical characteristics of leaves of host plants ( Mound, 1963); ventrally, caudal and thoracic tracheal folds marked, usually finely stippled.

Bemisia is probably the whitefly genus best known to general and agricultural entomologists. This is because of the notoriety of one species in particular, B. tabaci (Gennadius) , a pest of many agricultural crops and vector of plant virus diseases. This is discussed further in the account of B. tabaci , below. The genus currently includes just over 40 species, and is known from all geographical regions of the world. There is still speculation about the geographical origin of the genus.

Mound (1963) demonstrated experimentally that puparia of B. tabaci display great phenotypic variation, apparently dependent on the physical characteristics of leaf surfaces. Phenotypic variation of the puparial stage appears to be a generic trait, and caution needs to be exercised before visible morphological differences are regarded as being more than intraspecific variation. However, it is felt that some puparial characters of one taxon found in Belize are sufficiently constant to warrant its description as a new species, below. A few other specimens from Belize are not assigned to species with any certainty.

One Belize species (undetermined genus #2, species 1, figure 136), from Lonchocarpus rugosus ( Fabaceae : Papilionoideae ), has puparia somewhat resembling those of Bemisia species , but the nature of the moulting sutures, medially unreduced abdominal segment VII, curious dorsal tuberculate glands, lingula with basal lobes, and lack of submarginal setae all preclude inclusion in Bemisia , and its generic position is not certain: a single specimen from Lonchocarpus atropurpureus appears to be congeneric with it (see Appendix 1).

Figures

FIGURE 24. Bemisia centroamericana sp. nov., puparium, dorsum (see Fig. 109 for photograph).

FIGURES 25–28. 25–27, Bemisia tabaci (Gennadius), puparia, demonstrating variation within the species, 27 with enlarged detail of vasiform orifice and caudal setae; 28, Aleuroglandulus striatus Sampson & Drews, puparium (after Russell, 1944), with enlarged detail of thoracic tracheal comb, and setae at base of middle leg (see Fig. 88 for photograph).