Paralecanium machili Takahashi, 1933

Joshi, Sunil, Gupta, Ankita, Shashank, P. R., Pai, Sachin G., Mohan, M., Rachana, R. R., Dubey, Vinod Kumar, Sandeep, Angalakuditi & Deepthy, K. B., 2022, Recent adventive soft scale insects (Hemiptera: Coccomorpha: Coccidae) and mealybugs (Hemiptera: Coccomorpha: Pseudococcidae) in India, Zootaxa 5194 (2), pp. 213-232 : 221-222

Paralecanium machili Takahashi

Paralecanium machili Takahashi 1933: 37 . Hodgson & Williams 2018: 105–107 .

Podoparalecanium machili Tao, Wong & Chang 1983: 100 .

Material examined: INDIA, Karnataka, Kemmangundi, N 13.5500°, E 75.7500°, on Cinnamomum tamala (Buch.- Ham.) T. Nees & C.H. Eberm. ( Lauraceae ), 4.ii.2021, Sunil Joshi coll., 30 ♀♀.

Appearance in life ( Fig. 1c ): Often found adjacent to major leaf veins. Adult female very dark brown or glossy black, lighter on margin and submarginal areas and stigmatic clefts, colour becoming intense in median area anterior to anal plates; anal plates light reddish. Body subcircular or asymmetrical and slightly deltoid, almost flat but slightly convex in the median area; dorsum covered with numerous minute pits and divided into irregular tessellations by narrow smooth bands, of which a single median band runs from anal plates towards head and 6 or 7 curved horizontal bands ramify from medial band to margin. Nymphs transparent yellow.

Diagnosis of slide-mounted adult female (n=30): Body almost triangular, broadest posteriorly across abdomen ( Fig. 4q ), narrower anteriorly, asymmetrical and rounded at both ends. Marginal setae each fan shaped ( Fig. 4a ), wider than long. Stigmatic clefts deep, each with a sclerotized inner margin and containing 3 stigmatic setae ( Fig. 4b ). Eyespots oval ( Fig. 4c ), situated near margin.

Dorsum: Derm with small areolations near margin, becoming larger in a broad submarginal band ( Fig. 4d ), these becoming darker and unclear medially. Clear areas present only on abdomen ( Fig. 4e ), absent from head and thoracic segments. Setae each 4–5 µm long, curved with a blunt apex ( Fig. 4f ), sparse, more numerous near margin, perhaps absent medially (not visible due to high degree of sclerotization). Pores of three types: large pores with a sclerotized margin ( Fig. 4g ), common on submargin; smaller pores, lacking a sclerotized margin, appearing as a smaller clear spot in sclerotized derm ( Fig. 4h ), arranged in a polygonal pattern; and minute simple pores, each with an inner ductule, also forming a sparse polygonal pattern. Anal plates each with a rounded outer angle ( Fig. 4i ), 1 or 2 small pores medially and 2–4 small setae near apex.

Venter: Anogenital fold with 1 small seta on each side on anterior margin ( Fig. 4j ), each lateral margin with 1 seta at anterior end, and 2 setae laterally ( Fig. 4k ). Anal ring with 6–8 setae ( Fig. 4p ). Multilocular pores present on either side of genital opening ( Fig. 4l ), also on 1 or 2 abdominal segments. Spiracular disc pores ( Fig. 4m ) forming a narrow band of 10–12 pores between each spiracle and margin on short side; longer side of body with 18–20 pores present in each band. Legs fairly well developed, each with tibio-tarsal segmentation. Tarsal digitules slightly longer than claw digitules, with capitate apices, equal in size; claw digitules both broad and about same width; claw without a denticle ( Fig. 4n ). Antennae each with 6 segments ( Fig. 4o ).

Comparison: Hodgson and Williams (2018) provided an excellent taxonomic illustration and detailed description of this species in their revision of the soft scale genus Paralecanium ; only one species of Paralecanium , P. maritimum (Green) was known from India before their study. Paralecanium maritimum possesses large dorsal pores, each 5–7 µm wide, whereas such large dorsal pores are absent in P. machili , which has smaller pores each only 4–5 µm wide. Paralecanium machili has marginal ornamentation in the form of strong sclerotized “dashes” at right-angles to margin, which is not present in P. maritimum .

Ecological notes: Paralecanium machili was collected in large numbers on Indian bay leaf ( Cinnamomum tamala ), with at least one scale insect per leaf. The scale may restrict itself to higher altitudes on host plants belonging to Lauraceae , the only family on which it has been recorded so far ( García Morales et al. 2016).

Figures

FIGURE 1. Live appearance of: a. Maacoccus piperis (Green); b. Kilifia deltoides De Lotto; c. Paralecanium machili Takahashi; d. Fistulococcus pokfulamensis Hodgson & Martin; e. Antonina thaiensis Takahashi; f. Formicococcus simplicior (Green).

FIGURE 4. Paralecanium machili Takahashi, diagnostic characters of slide-mounted adult female. a. Marginal setae; b. Spiracular setae; c. Eyes; d. Dermal areolation; e. Clear areas on derm; f. Dorsal setae; g. Dorsal large pores with sclerotized margin; h. Dorsal small pores; i. Anal plates; j. Setae on anterior margin of anogenital fold; k. Setae on lateral margins of anogenital fold; l. Pregenital disc pores; m. Spiracular pores; n. Leg without tibiotarsal sclerosis; o Antenna; p. Anal ring; q. Female habitus.