Metaleurodicus essigi Martin 2008, comb. nov.
Creators: name: Martin, Jon H.
Publisher: name: Zenodo
Year: 2008
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Aleyrodidae
Metaleurodicus
Metaleurodicus essigi

description: Metaleurodicus essigi (Sampson & Drews) comb. nov.   
(Figs 73–75)  
 Aleurodicus essigi Sampson & Drews, 1941: 147. Lectotype puparium, here designated, Mexico (UCD).   
Redescription, from lectotype specimen  
 PUPARIUM. Habitus. Original description said “body covered by coating of mealy wax and four pairs of shiny wax filaments which arise from the dorsum [from the large abdominal compound pores], and are many times the length of the body and make the insect very conspicuous”. Margin. Outline oval, 0.8 mm long, 0.5 mm wide, widest at abdominal segment IV (n=1). Margin irregular, not toothed. Dorsum. Longitudinal moulting suture reaching puparial margin; transverse moulting sutures damaged (Fig. 75). Abdominal segment VII not significantly reduced medially. Abdominal segmentation distinct, especially between segments III/IV to VI/VII, where the division is visible almost to puparial margin (Fig. 75). Pro-/mesothoracic and meso-/metathoracic divisions subtly visible submedially. Two pairs of thoracic cicatrices present (scars of third-instar compound pores, figure 73). Vasiform orifice (Fig. 74) rounded-cordate; operculum trapezoidal, its posterior margin very shallowly “m”-shaped, bearing a pair of stout setae; lingula head tongue-shaped, densely covered by seta-like spinules, bearing the normal 4 stout setae; lingula not reaching posterior puparial margin, but its setae overlapping margin. Chaetotaxy. A probable anterior marginal seta visible on one side. A pair of posterior marginal setae (56µ long), and a pair of eighth abdominal setae (8µ long, anterior to vasiform orifice) present; submargin with 12 pairs of setae (including the nominal caudal pair), ranging from 15µ (anteriorly) to 30µ (the posteriormost pair); submedian cephalothoracic setae entirely absent (Fig. 73). Pores. Cephalic and posterior two pairs of compound pores 22µ in outer diameter, rather “bell-shaped” (Fig. 74). Abdominal compound pores on segments III–VI extremely large, 60–80µ in outer diameter, each with a sword-like axial process. Immediately within puparial margin, on the abdomen only, lies a single row of widerimmed pores about 9µ in diameter (Fig. 74), about 16 on one side of body and 18 on other (damage makes accurate count impossible); on the cephalothoracic plates pores of this type are absent (Fig. 73). Dorsal disc sparsely punctutated by loculate pores and unassociated porettes, with a very few (slightly larger) loculate pores situated near puparial margin on cephalothoracic plates. Venter. Ventral abdominal setae not discernible in lectotype. Legs typically robust and two-segmented, smooth, each with a pronounced apical claw. Antennal apices extending to bases of fore legs, their own bases anterolateral to fore legs. Tracheal folds absent.   
DISTRIBUTION. Neotropical Region – Mexico.  
 MATERIAL EXAMINED. Lectotype puparium here designated, MEXICO, on cliffs at Acapulco, Guerrero, on shrub, iii.1926 (G.F.Ferris, #347) (UCD 850).   
 COMMENTS. The absence of submedian cephalothoracic setal pairs, combined with the presence of loculate simple pores across the dorsum precludes inclusion in Aleurodicus, within the definition of Martin (2004) and adopted here. Indeed, this species only has dorsal simple pores of two types (loculate and porette), whereas the majority of Aleurodicus species have at least three types of simple pores, combined with a much greater pore density in at least some areas of the dorsal surface. Whilst the four pairs of very large compound pores are certainly atypical for Metaleurodicus, they are not typical for Aleurodicus, either. If anterior marginal setae are indeed present then that character also suggests exclusion from Aleurodicus. It is felt that essigi is most suitably accommodated within Metaleurodicus (comb. nov.).   
 Only a single specimen is known, but the description did not state this. Thus, the sole known specimen must be regarded as a syntype: it is therefore formally here designated the lectotype for future stability.
description: Published as part of Martin, Jon H., 2008, A revision of Aleurodicus Douglas (Sternorrhyncha, Aleyrodidae), with two new genera proposed for palaeotropical natives and an identification guide to world genera of Aleurodicinae, pp. 1-100 in Zootaxa 1835 (1) on page 54, DOI: 10.11646/zootaxa.1835.1.1, http://zenodo.org/record/5127230