Nealeurodicus petiolaris, John H. Martin, 2004

John H. Martin, 2004, Whiteflies of Belize (Hemiptera: Aleyrodidae). Part 1 — introduction and account of the subfamily Aleurodicinae Quaintance & Baker, Zootaxa 681, pp. 1-86 : 59-61

Nealeurodicus petiolaris sp. nov.

( Figs 37–39, 117–118, 129–130) PUPARIUM. Habitus. Immature stages of the extensive type sample all occurred on the woody petioles and young stems of their sapling host (Figs 129–130), and were vigorously attended by ants, Dolichoderus bispinosus (Olivier) . A ragged marginal fringe of short waxy filaments is present, and undisturbed individuals, viewed in lateral aspect, can be seen to have a very fine secreted filament issuing from the position of each compound pore. A crust of whitish secretion covers the dorsum, of variable opacity depending (apparently) on the age of the individual, but the vasiform orifice is always uncovered, appearing black: in some individuals, the puparia appear sugary­white, and the covering may be sufficiently robust to be removed and slide­mounted ( Fig. 38). In specimens that are approaching the emergence of adults, the dorsum is also raised away from the venter, supported by a vertical waxy palisade (Fig. 129), with the dorsum slightly domed; but less mature specimens are much more flattened. Margin. Outline elongate­oval, very slightly more obtuse anteriorly than posteriorly, 1.90–2.36 mm long, 1.17–1.40 mm wide, generally widest at abdominal segment III/IV (n=18). Margin with very shallowly castellate, almost contiguous, teeth, but only a slight degree of down­curling (which usually occurs in slide­mounted specimens) places outer­submarginal tubercular ridges in relief as irregular crenulations (Fig. 117a,b), fewer than 10 occupying 0.1 mm of margin at mid­length of puparium; margin modified at tracheal openings as combs of very fine, rounded teeth opposite forelegs (Fig. 117a) and between caudal setae. Dorsum. Cuticle variably pigmented, the coloration tending to indicate rays leading mesad from puparial margin, darkest cephalically, on mesothorax and on abdominal segments III/IV and VII/VIII ( Fig. 37); often a pigmented longitudinal band encompassing the submedian depressions on either side of body. Longitudinal moulting suture reaching puparial margin; transverse moulting sutures becoming indistinct subdorsally. Dorsal disc generally smooth. Abdominal segment VII medially longer than segment VIII anterior to vasiform orifice, and hardly shorter than segment VI (Fig. 117). Submedian abdominal depressions narrow but distinct from medial parts of abdominal intersegmental folds (Fig. 117); intersegmental folds becoming indistinct distal to submedian depressions. Vasiform orifice (Fig. 117) roundedtriangular, little longer than wide, slightly raised posterolaterally where the outer margin is roughened and is apically developed into a transverse boss; inner lateral margins of vasiform orifice also roughened, and floor of orifice with reticulate patterning; operculum trapezoidal, laterally curved, with a fine pair of setae situated on its posterior margin; lingula head finely spinulose, similar in shape to vasiform orifice, just overlapping apical boss of vasiform orifice, bearing the usual 4 stout subapical setae. Chaetotaxy. With 12 pairs of robust, hair­like setae in extreme outer submargin, including the nominal caudal pair, all similar in length to vasiform orifice; posterior marginal setae often a little longer than submarginal setae (Fig. 117), but anterior marginal setae absent; single submedian pairs of cephalic, pro­, meso­ and metathoracic and eighth abdominal setae present, similar to submarginal setae; eighth abdominal setae situated lateral to anterior part of operculum. Pores. Single pairs of compound pores present cephalically and on abdominal segments II, IV, V and VIII, the pores on segment VIII situated just posterior to apex of vasiform orifice (Fig. 117). All compound pores similar (Fig. 117c), ring­like, each 25–30 µ m in diameter, the axial lumen with tightly bundled rod­like structures which hardly emerge beyond pores; outer torus of each compound pore with subcircular “spinneret” cells (terminology of Quaintance & Baker, 1913) almost always forming a single ring of 10–18 cells. Whole of dorsum densely punctuated by evenly­distributed, mostly quadrilocular, simple pores (Fig. 117d), including between vasiform orifice and pockets; small wide­rimmed pores also occur, most in small aggregations of 2–5 pores bounding submedian zone and in outer subdorsum; somewhat more numerous aggregations of these pores present lateral to abdominal pockets (segment VII/VIII boundary) and to vasiform orifice (Fig. 117d). Ve nter. Ventral abdominal setae underlying posterolateral margins of vasiform orifice very long, but finer than dorsal submarginal setae. Posterior abdominal spiracles almost underlying compound pores on abdominal segment VIII; anterior to these spiracles is a pair of “pads” of unknown function (Fig. 118). Legs typical for Aleurodicinae , bisegmented and smooth; a fine seta situated at base of each middle and hind leg (Fig. 117), and a few minute setae present on distal segment of each leg. Antennae typical for Aleurodicinae , their apices reaching to articulations of middle legs (Fig. 117). Caudal tracheal fold indicated by a narrow band of tiny black spinules (Fig. 118); thoracic tracheal folds much wider than marginal combs, marked by faint boundary folds but not spinulose.

ADULT FEMALE. Several adult females emerged in culture, but males remain unknown; neither is there any sign of developing males in any of the slide­mounted puparia. The females are very large, fore wings and body lengths each about 3 mm, and wings and body are unusually darkly pigmented for any aleurodicine (Fig. 130), with the fore wings being almost covered by dark clouds, and the wing margin sharply emarginate at the confluence with the anal vein; the hind wings are dusky, with the radial vein lined with darker pigment. The abdomen has four pairs of large ventro­lateral wax plates. Abdominal tergites II–VIII and all thoracic plates are darkly pigmented. Antennae 7­segmented.

MATERIAL EXAMINED. Holotype puparium, BELIZE, CFR, Las Cuevas, Saffron trail, on Protium glabrum (Burseraceae) , 06.iv.2003 (J.H.Martin #7857) ( BMNH). Paratypes: 78 puparia, 8 third­instar larvae, 1 third­instar / puparium mid­moult, 22 adult females, same data as holotype ( BMNH, CDFA, USNM); numerous puparia dry on stems, residue of type sample ( BMNH).

ETYMOLOGY. The specific epithet reflects the petiole­feeding habit of the immature stages of this species.

COMMENTS. N. petiolaris has a similar distribution of compound pores to Ceraleurodicus neivai ( Bondar, 1928) , but N. petiolaris clearly belongs to Nealeurodicus , possessing the generic characters discussed above. Also, unlike those of N. petiolaris , the puparia of C. neivai have a pair of tiny compound pores located in the submargin that, unusually, appear to be on the same segment (VII) as the posteriormost large abdominal pair; the presence of more than one pair of compound pores per segment is abnormal [the posteriormost compound pores in N. petiolaris are situated closer to the median line, on segment VIII].

N. petiolaris is the only Belizean whitefly (in either subfamily) to have been found favouring the woody stems and petioles of its host. Indeed, not a single specimen was observed on a leaf, despite the extensive colony comprising several hundred individuals massed on the stems and petioles of their sapling host. Also quite unusually, this colony was vigorously attended by ants, Dolichoderus bispinosus . The combination of petiolefeeding, large size, strong ant­attendance and initial absence of adults led to a provisional assumption, in the field, that this was a colony of scale insects (Coccoidea). Ant­attendance may be part of the reason for a very low degree of parasitism, only one pre­emergence adult of an Encarsia species, belonging to the E. luteola ­group (A. Polaszek, pers. comm.), being found while slide­mounting material, and very few of the puparia showed parasitoid emergence holes.