Disiphon russellae, Martin, 2005

Martin, Jon H., 2005, Whiteflies of Belize (Hemiptera: Aleyrodidae) Part 2 - a review of the subfamily Aleyrodinae Westwood, Zootaxa 1098 (1), pp. 1-116 : 43-44

Disiphon russellae sp. nov.

( Figs 33–34 , 113)

PUPARIUM. Habitus. Immature stages feed lined along major leaf veins under leaves, each with cephalic margin abutting the vein. Cryptic when feeding, with no visible secretions (even from the siphons). Post­emergence, the pupal case is glassy and much distorted. Eye spots of developing adults clearly visible prior to emergence. A few individuals with a median cephalic patch of brownish cuticle. Margin. Outline broadly oval, subtly acute anteriorly and with caudal tracheal teeth slightly protuberant, 0.96 –1.14 mm long, 0.70–0.88 mm wide, generally widest at abdominal segment II/ III (n=25). Margin regularly crenate, 11–13 apically rounded teeth per 100 m, the teeth slightly larger in vicinity of tracheal openings, but not in the form of a significantly differentiated comb. Dorsum. Longitudinal moulting suture reaches puparial margin, with a pronounced keel occupying the middle third of its length ( Fig. 34 ); transverse moulting sutures form an inverted “ V ” (Fig. 113), before curving anteriad and terminating in subdorsum. Mesometathoracic suture pronounced, straight, only visible submedially, intersecting the confluence of longitudinal and transverse moulting sutures; cephalic/prothoracic junction in the form of oblique folds, mirroring the inverted “ V ” of the transverse moulting sutures to form an “X”­shaped feature; abdominal segmentation clearly marked only submedially, rhachisform, with a subtle radial arm extending towards base of each elongate siphon; abdominal segment VII not significantly reduced medially. Vasiform orifice ( Fig. 33 ) subcircular, its floor characteristically patterned as shown, the whole structure located on a triangular extension of the abdominal rhachis; operculum trapezoidal, occupying about two­thirds of orifice, almost obscuring the lingula; head of the lingula can just be seen to be spinulose and bisetose apically. Caudal furrow absent. Chaetotaxy. Anterior and posterior marginal setae present, fine. Single pairs of cephalic and eighth abdominal setae 55–85 m, stout, acute; meso­ and metathoracic pairs somewhat shorter; caudal setae similar but longer, 120–170 m. Mesal to marginal tooth­base folds, extending anteriorly from abdominal segment III, is an uneven line of tiny setae and spine­like structures that may be setal bases, with usually 10 discernible as setae on each side of puparium. Pores & glands. Siphon­like glands of two types present (Fig. 113): one cephalic and three abdominal pairs of the elongate type present in outer subdorsum, expanded but rounded apically, up to 220 m long, the apical pore leading to a channel which is clearly visible near siphons apex, and a tiny dark porette visible adjacent to the pore; the short, thimbleshaped type represented by one subdorsal and one submedian cephalic pair, two subdorsal thoracic pairs, and four subdorsal and one submedian abdominal pairs, each with a central pore/glandular channel and an offset porette (as also seen apically on the elongate siphons). Faintly marked pore/porette pairs present in a row mesad of submarginal tiny setae, and scattered over dorsal disc; a slightly more pronounced pairing on each side of rhachis on abdominal segments II– V & VII. Venter. Ventral abdominal setae fine, similar in length to vasiform orifice. Legs normal, each with an apical adhesion pad. Each middle and hind leg with a single tiny basal seta. Antennal bases antero­mesal to, and antennae similar in length to, forelegs. Rows of very fine submedian spinules present abdominally. Thoracic and caudal tracheal folds not marked .

MATERIAL EXAMINED. Holotype puparium, BELIZE, CFR, on Piper sp. (Piperaceae) , 06.xi.1994 (J.H.Martin #6462) ( BMNH). Paratypes: 33 puparia, 1 thirdinstar larva, 16 adult females, same data as holotype ( BMNH); 41 puparia, 8 third­instar larvae, same locality, on unidentified seedlings of Lauraceae , 18.xi.1994, 22.xi.1994, 30.xi.1994 (Martin) ( BMNH, USNM); 6 puparia, same locality, on Chiococca ? alba ( Rubiaceae ), 01.vi.2004 (Martin); 9 puparia, same locality, on Nectandra ? colorata ( Lauraceae ), 09.vi.2004 (Martin) ( BMNH).

ETYMOLOGY. Named for Louise M. Russell, who recognised and described the unique combination of characters that define the genus Disiphon , contributed to the study of Sternorrhyncha for over 50 years, and who celebrated her centenary as this manuscript neared completion.

COMMENTS. D. russellae differs from the only other described species, D. dubienus (Bondar) , in possessing many fewer siphon­like glands, and in the elongate type being very much longer than in D. dubienus .

Figures

FIGURES 29–34. 29–32, Aleuroglandulus inanis sp. nov., puparium (see Figs 87, 139 for photographs). 29, posterior dorsal detail; 30, detail of floor of vasiform orifice; 31, legs and legbase spines; 32, cephalic setae and geminate pore/porette pairs. 33–34, Disiphon russellae sp. nov., puparium (see Fig. 113 for photograph). 33, posterior dorsal detail, showing both types of dorsal siphon­glands; 34, longitudinal moulting suture, cephalic setae, short­type of siphon­glands and geminate pore/porettes.