Pedroniopsis beesoni Green

Hodgson, Chris J. & Williams, Douglas J., 2016, A redescription of the monotypic felt scale insect genus Pedroniopsis Green (Hemiptera: Coccomorpha: Eriococcidae) from India and Burma, Zootaxa 4137 (1), pp. 146-150 : 147-149

Pedroniopsis beesoni Green

Pedroniopsis beesoni Green 1926: 59 –60.

Material studied. Lectotype (here designated) + paralectotype adult females: INDIA: Ganjam, on Shorea robusta (Dipterocarpaceae) , no date, C.F.C. Beeson (but see under Comment below the description regarding collection site) ( BMNH): 1 slide with 5 adult females (condition fair-good; lectotype specimen that nearest the label “ Type ”). Also 2 further slides with identical labels, one with a single good specimen and other with 6 mainly poor specimens (including 3 very young adult females) ( BMNH). In addition, there are 5 slides with 15 specimens (14 adult females and a possible late nymph) in the BME, sent by Green to G.F. Ferris at Stanford University, California, and 2 slides with 5 adult females in the USNM, probably sent to Morrison at the USDA, Washington. These have the date of collection as 8.ii.1924, but omitted from Green’s description and on his slides. Otherwise all these slides have the same collection data as those from the BMNH, and can therefore be considered to be paralectotypes.

Also BURMA, no other location data, from galls of Beesonia dipterocarpi Green (Beesoniidae) on Dipterocarpus tuberculatus (Dipterocarpaceae) , no date, coll. Robson ( BMNH): 1 slide with 4 adult females (fair but full of fungal hyphae).

Note: description taken mainly from the five specimens on the type slide.

Adult female ( Fig. 1 ). Unmounted specimens. Adult female regularly ovate, dried specimens reddish ( Green, 1926: 59). Described by Beeson (1941: 75), probably from live material, as producing white cottony filaments but otherwise exposed. On bark ( Ramakrishna Ayyar (1930: 55).

Mounted specimens. Body oval, 1.3–1.4 mm long, 0.85–0.95 mm wide. Anal lobes absent.

Dorsum. Derm of very young specimens more or less sclerotised throughout, with sclerotisations broken into numerous small interlocking plates, giving a reticulate pattern. On older specimens (type specimens), these reticulated plate-like sclerotisations remain unchanged in shape and size but, as the derm becomes swollen, each plate is now separated by a wide area of membranous derm and appears as a spot; each plate about 5–8 µm wide, but very variable in shape; fairly evenly distributed throughout but sparse or absent in a few areas, mainly medially on head and thorax. Dorsal setae strongly spinose, similar to marginal setae but shorter, each 12–25 µm long with a broad base and narrow basal socket, and usually with a bifid apex; in a pair of medial longitudinal lines and more randomly submedially and submarginally; frequency very variable between specimens, but probably with a maximum of 13 and a minimum of perhaps 8 setae in each medial longitudinal row; when 13, possibly distributed as follows: 3 pairs on head, a pair on each thoracic segment and 7 pairs placed segmentally on abdomen; seta at most posterior end, very close to marginal setae, cone-shaped and about 5–8 µm long (one specimen with one seta 20 µm long); those submedially and submarginally similar to those medially, sparsely distributed with about 5–7 on each side submedially and 2 or 3 on each side submarginally. Dorsal microducts present, each about 3 µm long with a possibly bilocular orifice, placed in a smaller sclerotised plate; frequent. Other pores and setae absent.

Margin. Marginal setae spine-like, similar to those on dorsum but longer, each 20–30 µm long; some longer setae with a sharp apex; frequency around margin very variable but probably with a maximum of about 50 per side but some specimens (possibly damaged during mounting) with as few as about 30; many marginal setae with areas of derm slightly sclerotised around their base, particularly those nearest anal ring. Stigmatic areas absent and without stigmatic clefts. Eyespot on ventral margin, each 17–20 µm widest.

Venter. Derm membranous apart from a series of mildly spot-like sclerotised plates in a band around submargin. Loculate pores, each 3.5–4.0 µm wide with 5 loculi, in broad bands across abdominal segments IV–VIII, but rare or perhaps sometimes absent on IV and becoming more frequent posteriorly; also in a narrow to broad band around entire submargin, perhaps sparsest along thoracic margin. Spiracular disc-pores, each about 3 µm wide with five loculi (but of a subtly different structure to those submarginally), in groups of 2–5 just laterad to each peritreme. Ventral microducts of 2 sizes, both possibly oval in cross section and divided by a longitudinal septum: (i) a broader and slightly shorter duct, each about 13 µm long and 2.5–3.0 wide, in groups of 1–3 submarginally on abdominal segments IV–VIII; and (ii) a longer and narrower duct, each about 14–16 µm long and 1.0–1.5 µm wide, frequent in bands across abdominal segments IV–VIII. Ventral tubular ducts and other ventral pores apparently absent. Ventral setae flagellate, quite frequent in bands across abdominal segments IV–VIII where each 18–23 µm long, but shorter and much less frequent more anteriorly; submarginal setae few; interantennal setae not clearly differentiated. Antennae 3 segmented; basal 2 segments apparently scape and pedicel; apical segment probably composed of other segments fused; length 75–80 µm long; scape with 1 seta, pedicel with 1 seta + a campaniform sensillum; apical segment about as long as other 2 segments combined, with about 8 fleshy and setose setae. Frontal lobes absent. Clypeolabral shield about 115–125 µm long; without clypeal setae; labium at least 2 segmented, with 4 pairs of setae. Spiracles very small, each peritreme 9–10 µm wide; apparently without an apodeme. Legs moderately well developed, with all 5 segments; lengths (µm) for metathoracic leg: coxa about 68–70; trochanter + femur 85; tibia 43–45; tarsus 50–53; claw 16–17; coxa with 2 or 3 setae; trochanter with 2 setae and 2 oval campaniform sensilla in a transverse line on each side; hind coxa and femur without translucent pores; tibia without setae; tarsus with 2 or 3 setae and with a campaniform sensillum; tarsal digitules quite long and capitate; claw digitules shorter and possibly not capitate; claw with a strong denticle. Anal ring just on venter at posterior end, about 25 µm long and 25–27 µm wide, with pores and 3 pairs of setae, each seta about 40 µm long; also with a narrow sclerotised band around anterior margin and with a pair of anterior suranal setae, each about 8–10 µm long; posterior suranal setae occasionally present, each slightly spinose and 5–8 µm long.

Comments. We agree with Green (1926) that the genus belongs to the family Eriococcidae (sensu lato) because the dorsal setae are spine-like although unusually bifid at the tip. Also microducts are present, quinquelocular pores are present at least on the venter, the setae on the legs are very few, the apical segment of each antenna is not swollen, the trochanteral pores are orientated transversely (not along the trochanter-femur articulation as in the family Pseudococcidae ) and the anal ring possesses pores and six setae, all features found in most genera within the Eriococcidae . There is also an almost horizontal sclerotized bar with a pair of setae immediately anterior to the anal ring and this also is present in some genera of the Eriociccidae.

Although Green (1926) considered that P. beesoni lacked pores and ducts, these are clearly present. The presence of the Burmese specimens within the galls of Beesonia dipterocarpi is particularly intriguing indicating that P. beesoni may have a wide distribution across the northern part of southern Asia on species of Dipterocarpaceae .

The locality given by Green (1926) in his description of the species was Russelkonda (Russell Konda or Russell’s Hill), Ganjam, Madras. These place names, however, need some explanation. Russell Konda is now known as Bahnjanagar in Ganjam, a District in the State of Odisha (formerly Orissa) on the east side of India. Madras, as known by Green at the time, would have been Madras Presidency, an area covering most of southern India with parts of Odisha in the north and extending to the southern tip of India, with Madras as the capital. Madras (now known as Cennai) is the present capital of the State of Tamil Nadu, a long distance south of the type locality in Odisha State. The only locality known in India for the species is in Odisha State. Ramakrishna Ayyar (1930) mentions only Ganjam.

Figures

FIGURE 1. Pedroniopsis beesoni Green. Adult female. Where: A = marginal spinose setae; B = dorsal spinose setae; C = dorsal microduct; D = anal ring; E = appearance of dorsal derm on mature adult; F = posterior-most dorsal seta; G = ventral derm near posterior margin; H = multilocular disc-pores; J = broader ventral microduct; K = posterior leg; L = ventral seta; M = narrower ventral microduct; N = spiracular disc-pore; P = spiracle, and Q = antenna.