Setaleyrodes machili, Dubey, 2017

Dubey, Anil Kumar, 2017, Description of a new species, Setaleyrodes machili Dubey, sp. nov. (Hemiptera: Aleyrodidae) infesting Machilus odoratissima Nees (Lauraceae) in Western Himalaya, India, Zootaxa 4363 (2), pp. 291-300 : 293-299

Setaleyrodes machili sp. nov.

( Figs 1–35 )

Puparium. In life, puparium brown to jet black on Machilus odoratissima ( Figs 6, 7 ), shining, some puparia transparent white ( Fig. 5 ) on other unidentified host, without secretion of wax; elongate oval; broadest at metathorax to first abdominal region and narrow at posterior abdominal area; dimorphic, female 928–1075 µm long, 412–538 µm wide; male 725–850 µm long, 350–375 µm wide; found only on lower surface of leaves; scattered or attached with middle or side veins, 3–5 puparia per leaf.

Margin. Crenulate, a row of large crenulations close to and over shorter true crenulations, 25–28 short and 11– 15 large crenulations in 0.1 mm; margin slightly modified in thoracic tracheal pore opening areas ( Figs 9 , 17 , 26 ), but caudal tracheal pore clearly indicated with fine teeth.

Dorsum. Entirely tuberculate ( Figs 7 , 8 , 14, 15 , 23 ). Submargin not differentiated from the dorsal disc. Median length of cephalothorax (387–449 µm long in female, 332–448 µm long in male) shorter (164–167 µm) than abdomen (540–612 µm long in female, 499–500 µm long in male); mesothorax (female 67–75 µm, male 55 µm long) longer (13–17 µm in female and subequal in male) than metathorax (female 50–62 long, male 42–55 µm long). Median length of abdominal segments I–VII measured in female 55–63, 45–53, 60–68, 60–65, 60–65, 57– 65, 15–18 and 47–50 µm long, respectively and in male 45–48, 45, 45–57, 52–60, 50–53, 45–50, 12–13 and 40–45 µm long, respectively. Abdominal segment VII much reduced in middle length ( Figs 19 , 25 , 30 ), shorter than VI. Submedian area of meso- and metathorax with a pair of differentiated tubercles ( Figs 8, 10 , 16, 18 , 24 ). Abdominal segment sutures prominent, with pockets on submedian area ( Fig. 29 ); submedian depressions present on all the cephalothoracic and abdominal segments (two pairs on metathorax, three pairs on meso- and prothorax and two pairs on cephalous, between cephalic setae) ( Figs 12 , 14, 15 , 24, 25 ), abdominal depressions one pair each on segment I–VII, elongate in shape, reaching middle of segments. Longitudinal and transverse moulting suture reaching margin, faint on submarginal area. Caudal furrow continuous from the base of vasiform orifice to caudal tracheal comb ( Fig. 11 ), encircling widely vasiform orifice, furrow posterior to vasiform orifice filled with tubercles ( Fig. 28 ), these tubercles appear as transverse plates in slide mounted puparia ( Fig. 21 ), 55–78 µm long in female, 40 µm long in male; the distance measured from the base of vasiform orifice to the caudal tracheal comb opening is 122–132 µm long. Two pairs of geminate pores located between the first abdominal setae. The distance between geminate pore and associated porette is 1–2 times the diameter of the large pore itself ( Fig. 32 ). Pockets discontinuous.

Vasiform orifice. Situated in an elongate pit ( Fig. 28 ); not elevated, trapezoidal or elongate subcordate, posteriorly truncate ( Fig. 31 ), area posterior to vasiform orifice and caudal margin ornamented with transverse plates; female 50–65 µm long, 45–55 wide; male 42–55 µm long, 40–43 µm wide; operculum broadly subcordate ( Fig. 31 ), covering half the length of orifice, 25–30 µm long in both male and female, wider than long in both male and female, wider in female than male, 35–38 µm wide in female and 27–32 µm wide in male, operculum anteriorly slightly narrow, 17 µm wide. Lingula tip exposed, D-shaped, with a pair of small setae subapically ( Fig. 31 ).

Venter ( Fig. 33 ). Paired ventral abdominal setae 10–13 µm long, 43 µm apart in male, 52–63 µm apart in female ( Fig. 35 ). Antennae 37–43 (including 4 µm keel) µm long. Pro-, meso- and metathorax encircled by longitudinal ventral fold. The longitudinal ventral fold provided with a series of many microsetae ( Figs 13 , 34 ). Antenna reaching 1/3rd of prothoracic leg ( Fig. 22 ). Stipples absent in thoracic tracheal folds but present in caudal tracheal fold. Microsetae at base of pro-, meso- and metalegs and at base of rostrum present. Spiracles visible.

Chaetotaxy. Anterior marginal setae not discernable, posterior marginal setae 12–25 µm long. Cephalic, first abdominal and eighth abdominal setae small, pointed and much shorter than caudal setae. Cephalic 8–30 µm long, first abdominal setae pointed ( Figs 20 , 27 ), 20–45 µm long, eighth abdominal setae posterior to base of vasiform orifice, medio-anterior to operculum, 7–10 µm long; caudal setae on margin, laterad of caudal furrow margins, 70– 88 (including base 7 µm long) µm long.

Host plant. Machilus odoratissima Nees (Lauraceae) .

Distribution. India: Himachal Pradesh, Uttarakhand.

Material examined. Holotype. INDIA: Himachal Pradesh, Kufri, altitude 8600 feet, one puparium on slide, on Machilus odoratissima , 25.xii.2014, A. K. Dubey (NFIC-FRI). Paratypes. 30 puparia on 10 slides, several puparia in alcohol, data same as of holotype (NFIC-FRI); Uttarakhand: Dhanaulti, altitude 7500 feet, 51 puparia on 12 slides, on Machilus odoratissima , many puparia in 95% alcohol, 23.xii.2015, A. K. Dubey; Nainital, altitude 6800 feet, 20 puparia on 10 slides, on Machilus odoratissima , 12.i.2016, many in 95% alcohol, A. K. Dubey (Natural History Museum, London and A. K. Dubey private collection).

Etymology. The species is named after its host plant genus, Machilus .

Remarks. Puparia of this new species differ from all other known Setaleyrodes species in colour, shape, and by the absence of three pairs of long anterior marginal setae, and in having a reduced operculum and exposed lingula. This species is only known to occur in the high altitude area of Western Himalayan range.

Biology. This species is occurring in high altitude areas at 7500 feet in Western Himalaya where it is infesting leaves of the Machilus trees growing in the slopes of valley. In these mountains, only short time day visits can be made. During the collection of this species from 2014 to 2016, the population was found higher (3–5 puparia per leaf) during the cooler months from January to March with more infested leaves, and then lower from April, remaining almost scanty and constant (1–2 puparia per leaf) for the rest of the year, with fewer infested leaves. In all the collections made, this species was represented by fourth instars only except a single population where variation in pigmentation was observed during transformation from third instar to puparium. The second and third instar were white, the late third instar and transforming early fourth instars were brown, however, the late fourth instar were always found jet black but without wax. In all the collections, puparia were found without wax, and clearly visible on shiny and light bluish green under surface of host plant leaves. The new species lays its eggs in circle ( Fig. 1 ), which turn dark brown upon hatching ( Fig. 2 ). Only one circle of eggs was noticed per leaf.

Figures

FIGURES 1–7. Setaleyrodes machili Dubey sp. nov., habitus, 1, eggs in circle; 2, hatched egg; 3, 2 nd instar; 4, 2 nd and 3 rd instars; 5, earlystage puparium; 6,puparium transforming colour from white to brown; 7, puparium, late stage, black.

FIGURES 8–13. Setaleyrodes machili Dubey sp. nov., camera lucida drawings, 8, puparium, dorsal and ventral views; 9, thoracic tracheal pore area; 10, cephalothoracic tubercle; 11, caudal area and vasiform orifice; 12, abdominal depressions; 13, submedian ventral fold and legs.

FIGURES 14–22. Setaleyrodes machili Dubey sp. nov., holotype puparium, 14, cephalothorax; 15, abdomen; 16, moulting sutures and first abdominal setae; 17, thoracic tracheal pore area; 18, cephalothoracic tubercles; 19, median abdominal area, sutures and depressions; 20, first abdominal seta; 21, vasiform orifice and caudal furrow; 22, proleg and antenna.

FIGURES 23–28. Setaleyrodes machili Dubey sp. nov., SEM microphotographs, 23, puparium dorsal view; 24, cephalothorax; 25, abdominalarea; 26, margin; 27, 1 st abdominal seta; 28, vasiform orifice and caudal furrow.

FIGURES 29–35. Setaleyrodes machili Dubey sp. nov., SEM microphotographs, puparium, dorsal and ventral views; 29, abdominalpockets and depressions;30, abdominalsegment VII;31, vasiformorifice,lingula; 32, geminatepore;33, puparium, ventral view; 34, submedian ventral fold, microsetae; 35, caudal fold, ventral setae, stipples, spiracles.