Atrococcus groenlandensis, Gertsson & Hodgson

Gertsson, Carl-Axel & Hodgson, Chris, 2005, Four new species of mealybug (Pseudococcidae) and a new species of soft scale (Coccidae: Coccoidea: Hemiptera) from Greenland and redescriptions of a mealybug and a soft scale from Arctic Canada, Zootaxa 897, pp. 1-24 : 3-6

ATROCOCCUS GROENLANDENSIS Gertsson & Hodgson spec. nov ( Fig. 1 )

(Described mainly from 3 specimens in good condition)

Unmounted material. Not known.

Mounted material. Oval in outline, 1025–2600 µm long and 500–1000 µm wide; anal lobes moderately developed; antennae 8 ­segmented; legs normally developed; circulus absent; with 2 pairs of distinct cerarii plus a third which may be undifferentiated; oral rim ducts present.

Dorsum. Membranous, with frequent fine setae, each mainly 10–21 µm long but with some on head up to 27 µm. Trilocular pores quite frequent and fairly evenly distributed. Simple (discoidal) pores scarce throughout; also with 2 small convex pores dorsad to each scape. Cerarii clearly present on abdominal segments VII and VIII, each with two stout spinose setae (stoutest on VIII), length of cerarian setae on VIII 10–18 µm; with 5–6 auxiliary setae, longest about 33–40 µm; cerarian setae on segment VI barely differentiated from other setae, possibly sometimes absent. Ostioles membranous, each lip with 5–8 trilocular pores and 0–2 small setae. Oral rim ducts each 8 µm wide, distributed as follows: VIII 0; VII 4–6; VI 1 or 2; V & IV 2–4; III – I 1–6; meta­ to prothorax 2–6; head 6–8. Oral collar ducts of two sizes; larger ducts (each about 3 µm wide and 8 µm long) restricted to a small group marginally on abdominal segments II –VIII, each group with 1–5 ducts, most abundant on posterior segments; smaller ducts (each about 1.5 µm wide and 6–7 µm long) in transverse lines across abdominal segments, most abundant on segments IV & V. Multilocular disc­pores 6–7 µm wide, with 0 to about 12 on abdominal segments I –VII, mainly near margin but with up to about 6 along posterior margins of segments IV –VII. Anal ring 64–70 µm wide, with 6 setae, each about 100–125 µm long.

Venter. Membranous, with frequent fine setae, each 20–85 µm long, but some on head up to 110 µm; suranal setae 36–50 µm long; long anal lobe setae each 140–220 µm long. Trilocular pores frequent and fairly evenly distributed. Simple (discoidal) pores as on dorsum. Oral rim ducts similar to those on dorsum, with 0 or 1 marginally on abdominal segments I –V and on meta­ and mesothorax. Oral collar ducts of two sizes as on dorsum, with larger ducts along posterior margin of each segment, quite frequent on posterior abdominal segments, particularly laterally, but absent medially anterior to segment III, when restricted to near margin; possibly absent on mesothorax, but with a strongly defined group laterad to each procoxa, each group with 9–20 ducts; smaller ducts in a transverse line medially across segments, most abundant posteriorly on abdomen but with a few anteriorly as far as mesothorax. Multilocular disc­pores 6–7 µm wide, present on abdomen as follows (approximate totals across segment): VIII 36; VII 34 along posterior margin and 20 along anterior margin; VI 40 post. and 25 ant.; V 44 post. and 3 or 4 ant.; IV 26 post.

and 0–2 ant.; III 5 or 6 near margin only; II 2–4 near margin only; absent more anteriorly apart from 0–6 in a group with oral rim ducts laterad to each procoxa. Circulus absent. Eyespot about 30 µm wide. Antennae 8 segmented, 290–350 µm; scape with 4 setae; pedicel with 4 setae + a campaniform pore; segments III –VII each with usually 3–6 (normally 4) setae; preapical segment with 5 setae plus a fleshy seta; apical segment with 10 hair­like setae, 6 fleshy setae and 4 or 5 stiff setae near apex; apical seta about 33–35 µm long. Clypeolabral shield about 115–140 µm long; labrum about 100 µm long, with 11 pairs of setae. Spiracles: width of peritremes 17–22 µm. Metathoracic legs: lengths (µm): coxa 103–150; trochanter + femur 170–240; tibia 130–186; tarsus 74–87; claw 23–28; number of setae: coxa 10 or 11; trochanter 5 or 6 (longest 83–85 µm); femur 7–11; tibia 8– 11 (tibia with two spurs, each 20–22 µm long); tarsus 9 or 10; translucent pores quite abundant on lateral half of each metacoxa, occasionally with a few on femur but usually with some on dorsal half of tibia. Tarsal digitules: one thinner than other but both capitate; claw digitules both slightly longer than claw and capitate; claw without a denticle. Vulva obvious, between segments VII and VIII.

Material examined. HOLOTYPE Ψ: Evighedsfjord, Kangiussaq, on Viscaria alpina , 20.vii. 2003, S.T. Nielsen ( ZMUC): 1 / 1 adΨ + 1 paratype adɗ.

PARATYPE ΨΨ: GREENLAND: Evighedsfjord, Kangiussaq, on Viscaria alpina , 20.vii. 2003, S.T. Nielsen ( ZMUC): 4 / 5 adΨΨ.

Other material: Jameson Land, Muslingerbugt, 26.vii. 1994, pitfall trap, Jens Böcher; as previous, on Campanula gieseckiana ; Evighedsfjord, Kangiussaq, 20.vii. 2003, Epilobium angustifolium , Saxifraga tricuspidata , Potentilla tridentata ; Itivleq east, 22.vii. 2003, Melandrium affine /triflorum, Arctostaphylos uva­ursi, Salix arctophila, Artemisia borealis; as previous, 23.vii. 2003, Vaccinum sp., Salix glauca ; Ameralik, Eqalūit Ilordlit, 7.vii. 2003, on Coptis trifolia , Rumex acetosella ; as previous, 8.vii. 2003, Thymus drucei ; Buksefjorden east, 6.vii. 2003, no host; Kangerdluarssuk tugdleq, 25.vii. 2003, on Poa glauca , Dryas integrifolia ; Fiskefjord, Igdlutalik, 11.vii. 2003, Potentilla tridentata ; Fiskenaesfjorden, Amigfik, 3.vii. 2003, on Hieracium rigorosum ; Sisimiut (Holsteinborg), 27.vii. 2003, Campanula sp. ( ZMUC, BMNH, USDA).

Comment. The adult female of A. groenlandensis spec. nov. is very similar to that of A. cracens Williams , differing mainly in having many fewer multilocular disc­pores; specifically, A. cracens has groups of disc­pores submarginally and submedially on the dorsum of all segments, including head, except the preanal segment, whilst disc­pores are totally absent on A. groenlandensis anterior to segment IV. Additionally, A. cracens has a group of 15–27 disc­pores laterad to each procoxa, whilst the present species has only 0–6 disc­pores, significantly less than the number of oral collar ducts in the group (9–20) (number of disc­pores equals or exceeds number of oral collar ducts on A. cracens ). The cerarii on segment VI on A. groenlandensis also seem to be hardly differentiated, whereas they are more obvious on A. cracens , which may also have cerarii on segment V.

This would appear to be a polyphagous species, as is A. cracens .

Etymology: the species name groenlandensis is taken from the Danish name for Greenland, Grønland.

Figures

FIGURE 1. Adult female of Atrococcus groenlandensis Gertsson & Hodgson. Dorsal surface on left, ventral surface on right. On this and all other figures illustrating adult female Pseudococcidae: A = oral rim duct; B 1 = larger oral collar ducts; B 2 = smaller oral collar duct; C = trilocular pore; D = simple (discoidal) pore; E = small convex pore; F = dorsal multilocular pore; H = claw; K = coxal pores; M = anal lobe; N = apical antennal segment, and P = ventral multilocular disc­pore.