Valid Names Results

Aspidiotus rigidus Reyne, 1947 (Diaspididae: Aspidiotus)

Nomenclatural History

• Aspidiotus destructor rigidus Reyne 1947: 294. Type data: INDONESIA: Sangi Island, half way between Sulawesi [=Celebes] and PHILIPPINES: Mindanao, on coconut palm [=Cocos nucifera].. Syntypes, female, Type depository: Amsterdam: Institut voor Taxonomische Zoologie, The Netherlands; accepted valid name
• Aspidiotus rigidus Reyne, 1947; Borchsenius 1966: 267. change in status (level)

Common Names

• escama rígida del cocotero Watson2022a
• Rigid coconut scale Watson2022a

Ecological Associates

Hosts:

Families: 3 | Genera: 7

Foes:

Families: 4 | Genera: 9

Geographic Distribution

Keys

Remarks

• Systematics: GenBank accession numbers: MG940951, MG940952, MG940953 (Dao, et al., 2020) This species was first described as a subspecies of Aspidiotus destructor by Reyne (1947, 1948), who distinguished it from typical destructor mainly by biological features, as well as difference in scale structure. The phylogeny in Schneider, et al. (2018) suppports the separation of Aspidiotus destructor and A. rigidus, two pests of coconut palm that are very difficult to distinguish based on morphology. Some aspects of the live appearance and biology of A. rigidus facilitate its identification: 1. The cuticle of the adult female A. rigidus is extremely tough and rigid, which can be demonstrated by lifting the insect up off the leaf with the tip of a blunt needle, whereas the cuticle of A. destructor is delicate and flexible. 2. The life cycle is approximately 1.5 times longer than that of A. destructor. 3. The white egg skins left under the scale cover after hatching accumulate near the pygidium of A. rigidus, forming a white crescent under one-half of the scale cover. By contrast, in A. destructor, the white empty egg skins are distributed around the entire circumference of the scale cover. (Watson, et al., 2015)
• Structure: Female scale 1.8-2.1 mm in diameter, height 0.1-0.2 mm, more or less smoke-coloured, fibrous, sometimes with an irregular outline, caused by one or more incisions; exuviae of first and second larval stage measure 0.45 x 030 and 0.7 x 0.6 mm respectively (Reyne, 1948). Reyne (1948) described the A. rigidus scale cover as more or less smoke-colored than the more transparent A. destructor scale cover. Watson et al. (2015) redescribed A. rigidus scale cover as relatively flat, very thin, and transparent from pale yellow to occasionally chestnut brown, while A. destructor has a very thin and transparent but off-white to slightly yellow scale cover. The study and SEM photographs by Serrana, et al. (2023) validated these observations.
• Biology: Eggs develop within the female scale cover and are laid in groups of about 12. Nymphs move away and a crescent of while egg shells can be seen around the female. Females develop in 45-55 days. Very dry conditions may result in high mortality of eggs and young nymphs. (Kalshoven, 1981)
• Economic Importance: This species, that is morphologically closely related to Aspidiotus destructor is a serious pest of coconut palm in Sangi island, near Sulawesi, Indonesia (Reyne, 1947, 1948). The scale is dull skokey-white, tough and opaque. The female body is pale green or grey-green and the males are pale and bright yellow with a red thoracic band. (Kalshoven, 1981) A massive infestation on plantations of coconut, Cocos nucifera (L.) (Arecaceae), was observed in the Philippines by the coconut scale insect, Aspidiotus rigidus Reyne (Hemiptera: Diaspididae). The infestation caused a great decline in the coconut palms of the area, affecting around 50-70% of the coconut farms in 2013. Aspidiotus rigidus settles on the lower surface of the leaf, blocking the stomata and preventing the plant to photosynthesize which may even result to death (Watson et al., 2015)
• General Remarks: Description and illustration of adult female by Reyne (1947, 1948).

Illustrations

Citations