Aleurocybotus mojavensis von Ellenrieder & Bailey, 2022

Ellenrieder, Natalia Von & Bailey, James, 2022, Aleurocybotus mojavensis (Hemiptera: Sternorrhyncha: Aleyrodidae), a new whitefly species from California, Zootaxa 5174 (3), pp. 294-300 : 295-296

Aleurocybotus mojavensis von Ellenrieder & Bailey , sp. nov.

( Figs. 1–7 )

Etymology. This species is named after the Mojave Desert, biome encompassing its type locality.

Type material. Holotype: Slide mounted puparium, U.S.A., California, San Bernardino County, rocky slope above wash off Gold Park Road , 1 mi N of Joshua Tree National Park, 34.088697°N, 116.009282°W, on Aristida purpurea , 28.viii.2021, James Bailey coll., at CSCA . Paratypes: 70 slide-mounted puparia, same data as holotype, at BME, BMNH, CSCA, FSCA, NHMLA, USNM , and 10 puparia in ethanol, at CSCA.

Additional material: Slide mounted puparium [microphotograph examined], U.S.A., California, Riverside County, Palm Springs , San Andreas Canyon , on Gramineae , 8.viii.1968, J. L. Johnson & Ray Gill coll., CDFA 68 H 13 32, at USNM.

Description. Habitus. Occurring in aggregations on blades of grasses ( Fig. 1 ), where the copious flocculent white lateral wax on puparia makes their presence evident and partially obscures the body of the insects ( Figs. 2–3 ). Puparia dorsum flat and slightly sclerotized, median and submedian area brown, subdorsal and submarginal areas pale brown to yellow; venter membranous and slightly inflated in mature pupae, supported by a rim of marginal wax. Spent eggshells brown, attached to blades in irregular groups or rows. No adults were found, and there were no ants observed in attendance.

Slide-mounted characters ( Figs. 4–7 ). Outline elongate oval ( Fig. 4 ), 1.1 mm long [0.94–1.11, 1.04 ± 0.06], 0.52 mm wide [0.46–0.55, 0.51 ± 0.03], about twice as long as wide (2.1 [1.9–2.2, 0.07 ± 0.09]), widest between metathorax and abdominal segment I [mesothorax and abdominal segment IV]. Margin crenulate, with 16–18 [15–20] rounded teeth occupying 100 µm ( Fig. 5 ), not modified at tracheal openings; in slide preparations outer portion of submarginal area usually partially folded medially, so that crenulation is not evident laterally. Dorsum. Longitudinal and transverse molting sutures reaching puparial margin. Segmentation between head and prothorax [not always], mesothorax and metathorax, and abdominal segments well marked; abdominal segment VII not significantly reduced in length medially; submedian area with thoracic and abdominal depressions well indicated ( Fig. 4 ). Submarginal area with external half glandular, with subcircular glands and darker interglandular divisions ( Figs. 4, 5, 7 ). Vasiform orifice ( Figs. 6, 7 ) subcordate, with sides slightly convex, about as long as wide (1.07 [1.03–1.14, 1.08 ± 0.04]), inset from puparial posterior margin by about its own length (0.99 [0.86–1, 0.92 ± 0.05]); operculum subcordate, laterally slightly convex, about two thirds (0.67) as long as vasiform orifice [two thirds to half as long, 0.5–0.67, 0.6 ± 0.06]), its posterior margin slightly wider than head of lingula and distinctly narrower than its anterior margin, bearing fine setae; lingula spatulate, with head only slightly expanded, rounded, included within vasiform orifice, and covered in minute spinules ( Fig. 6 ) and with a pair of setae directed posteriorly broken off in holotype. Caudal furrow poorly defined ( Fig. 7 ). Chaetotaxy. Anterior and posterior marginal setae present, a little shorter than dorsal setae. Dorsal disc setae include single pairs of submedian cephalic setae, single pairs of subdorsal pro, meso, metathoracic and first abdominal setae, a pair of submarginal caudal setae, two pairs of submarginal setae placed anterior to caudal setae and anterolateral to posterolateral to vasiform orifice, occasionally a seta on one of both sides on subdorsum of abdominal segments IV and VI, and eighth abdominal setae placed at the level of anterior edge of operculum ( Fig. 6 ); all dorsal setae fine, with the eighth pair representing the longest, about as long as operculum length. Pores. Simple pores present, inconsistently paired, 10–12 [3–12] on each side of head, 1–4 [0–5] on each side of each thoracic segment, and 1–4 [1–6] on each side of each abdominal segment. Venter. Abdominal setae fine, underlying vasiform orifice. Legs ( Fig. 4 ) bisegmented; apical adhesion pad directed anteriorly on prothoracic legs and posteriorly on meso and metathoracic legs, the latter two with one or two minute basal setae. Antennae ( Fig. 4 ) with bases anterolateral to prothoracic legs and tips reaching base of mesothoracic legs [reaching base (presumably in females) to center (presumably in males) of mesothoracic legs]. Tracheal folds absent.

Diagnosis. Puparia of both Aleurocybotus cereus and A. mojavensis sp. nov. can be recognized in the field from those of A. graminicolus and A. occiduus by the copious lateral white wax secretions ( Figs. 1–3 ), which are absent in the latter two species whose puparia have limited amounts of clear wax on dorsum and venter and white translucent wax surrounding venter ( Quaintance 1899; Russell 2000; Martin 2005; Vejar et al. 2009). Microscopically, the glandular area secreting the lateral wax is evident as a dorsal submarginal band in A. cereus and A. mojavensis , whereas it is not evident in A. occiduus and A. graminicolus . In A. mojavensis , the glandular band occupies only the external half of the dorsal submarginal area ( Figs. 4, 5, 7 ), while in A. cereus it occupies its entire width.

Other differences between A. mojavensis and its congeners (differing characters for the other species in parenthesis) include: submedian thoracic and abdominal depressions well marked and wider than long on abdominal segments III–VI, Fig. 4 (faintly marked in A. cereus , longer than wide on abdominal segments III–VI in A. occiduus ); dorsum with simple pores and devoid of large pores, Fig. 4 (with simple pores associated with large pores arranged in a loose submarginal row and interspersed over dorsum in A. graminicolus and A. occiduus ); vasiform orifice subcordate with sides slightly convex, Figs. 6, 7 (cordate with sides rounded in A. cereus , subtriangular with sides approximately straight in A. graminicolus and A. occiduus ), inset from posterior margin by about its own length, Fig. 7 (inset by more than its own length in A. cereus , by less in A. occiduus and A. graminicolus ); operculum subcordate and laterally slightly convex, Fig. 6 (operculum trapezoidal and laterally rounded in A. cereus ), its posterior margin distinctly narrower than its anterior margin and slightly wider than head of lingula, Fig. 6 (posterior margin slightly narrower than its anterior margin and distinctly wider than head of lingula in A. cereus ); eighth abdominal setae anterior to widest section of operculum, Fig. 6 (posterior to widest section of operculum in A. occiduus ); caudal furrow poorly defined, Fig. 7 (marked by incomplete longitudinal ridges in A. occiduus and A. graminicolus ).

Figures

FIGURES 1–3. Aggregation of Aleurocybotus mojavensis sp. nov. on Aristida purpurea Nutt. in situ, near Gold Park Road, San Bernardino County, California, U.S.A.. Photographs by James Bailey, 28.viii.2021. 1: Habitus of host plant; 2: Close-up of glass blade; 3: Detail showing individual puparia with submarginal wax and some spent eggshells.

FIGURES 4–7. Holotype puparium of Aleurocybotus mojavensis sp. nov. 4: Habitus. 5: Detail of anterolateral portion at level of anterior seta showing crenulated margin and submarginal glandular band; 6: Close-up of vasiform orifice showing eight abdominal setae, operculum and lingula; 7: Detail of posterior portion of body showing submarginal glandular band, posterior abdominal setae, vasiform orifice and caudal furrow.