Palmicultor, Williams, 1963

Zarkani, Agustin, Ercan, Cansu, Apriyanto, Dwinardi & Kaydan, Mehmet Bora, 2023, Studies on mealybugs (Hemiptera: Pseudococcidae) in Indonesia, with description of a new species and three new country records, Zootaxa 5228 (2), pp. 157-172 : 165-168

Palmicultor cryptic species complex, species near palmarum (Ehrhorn)

( Fig. 3 )

Material examined. INDONESIA, Sumatra I., Bengkulu Province, Seluma district, Air Periukan, on Elaeis guineensis Jacq (Arecaceae) , 8 m a.s.l., 03°59′07″ S, 102°25′37″ E, 2.ii.2018, coll. A. Zarkani (AZ203), 3 ♀♀.

Appearance in life ( Fig. 3 ). Body of adult female covered with fluffy white wax secretion. The mealybugs live mainly on the fruits and are attended by ants ( Fig. 4 ).

Description of adult female (based on holotype and 2 paratypes) ( Fig. 4 ): Body oval, 1.98–2.42 mm long, 1.38– 1.48 mm wide. Eyes situated on margins, each 25–30 μm in diameter. Antenna 7 segmented, each 270–280 μm long,

with 4 fleshy setae each 22.5–30.0 μm long; apical segment 75–90 μm long, 22.5–30.0 μm wide, with apical seta 27.5–30.0 μm long. Clypeolabral shield 220–230 μm long, 175–185 μm wide. Labium 3 segmented, 110–120 μm long, 80–85 μm wide. Anterior spiracles each 60–65 μm long, 20–25 μm wide across atrium; posterior spiracles each 75–85 μm long, 40–45 μm wide across atrium. Circulus notched on each side with a strong middle constriction, 80–110 μm wide. Legs well developed; segment lengths for each posterior leg: coxa 115–135 μm, trochanter + femur 205–220 μm, tibia + tarsus 160–170 μm, claw 27.5–30.0 μm. Ratio of lengths of tibia + tarsus to trochanter + femur, 0.77–0.78: 1; ratio of length of tibia to tarsus, 1.2–1.4: 1; ratio of length of trochanter + femur to greatest width of femur, 3.41–3.60: 1; derm surrounding each posterior coxa with 40–50 translucent pores; coxa with 30–50 translucent pores; tibia with numerous translucent pores. Tarsal digitules capitate, each 27.5–30.0 μm long. Claw digitules capitate, each about 22.5–25.0 μm long. Both pairs of ostioles present, anterior ostioles each with a total for both lips of 28–40 trilocular pores and 4–6 setae; posterior ostioles each with a total for both lips of 58–60 trilocular pores and 6–8 setae. Anal ring about 95 μm wide, bearing 6 setae, each seta 160–165 μm long.

Dorsum. Derm membranous, with 16 pairs of cerarii around body margin, each cerarius with 2–5 enlarged conical setae and 3–5 auxiliary setae. Each anal lobe cerarius set on membranous cuticle and containing 3–6 enlarged setae 25–30 μm long, plus 55–57 trilocular pores and 3–5 hair-like auxiliary setae. Dorsal setae short and flagellate, each 30–110 μm long, scattered throughout dorsum. Trilocular pores, each 3–4 μm in diameter, scattered. A few multilocular disc pores present on thorax and abdomen.

Venter. Setae flagellate, each 30–110 μm long, longest setae located medially on head. Apical setae on anal lobe each 125–150 μm long. Multilocular disc pores, each 7–8 μm in diameter, present throughout venter, numbers on each abdominal segment as follows: I–III each with 60–70, IV 20–24, V 38–43, VI 100–110, VII 90–98, VIII + IX 36–38 and 125–145 on thorax and head. Trilocular pores, each 2.5–3.0 μm across, scattered throughout venter. Oral collar tubular ducts each 8–10 μm long, 4–5 μm wide, present throughout, but in bands across abdominal segments, as follows: VI 21, VII 15, VIII + IX 14.

Comments. The Indonesian specimen is a member of the P. palmarum cryptic species complex, which was discussed by von Ellenrieder et al. (2021). Members of this species complex have more than 12 pairs of cerarii; the derm surrounding each posterior coxa has 40–50 duct-like pores, and each hind coxa and hind tibia have numerous translucent pores. The dorsal setae in the Indonesian specimen are up to twice as long as those recorded previously in P. palmarum by Williams and Watson (1988) and Williams (2004). Even though we found some differences, we believe that some further studies must be done to decipher this species complex. Further molecular studies will be useful to resolve species concepts.

Figures

FIGURE 3. Palmicultor cryptic species group, species near palmarum (Ehrhorn), attacking Elaeis guineensis Jacq. fruits.

FIGURE 4. Adult female of a member of the Palmicultor palmarum (Ehrhorn) cryptic species group, from Indonesia, Sumatra I., Bengkulu Province, Seluma district, Air Periukan, on Elaeis guineensis Jacq. (Arecaceae).