28-11-2023 RIO SERPIS, GANDIA - MEDITERRANEAN BROCADE MOTH CATERPILLAR (Spodoptera littoralis)

Spodoptera littoralis, also referred to as the African cotton leafworm or Egyptian cotton leafworm or Mediterranean brocade, is a species of moth in the family Noctuidae. S. littoralis is found widely in Africa, Mediterranean Europe and Middle Eastern countries. It is a highly polyphagous organism that is a pest of many cultivated plants and crops. As a result, this species was assigned the label of A2 quarantine pest by the EPPO and was cautioned as a highly invasive species in the United States. The devastating impacts caused by these pests have led to the development of both biological and chemical control methods. This moth is often confused with Spodoptera litura.

African cotton leafworm is native to Africa and also resides in most regions of Middle Eastern countries such as Israel, Syria and Turkey. Specifically, the species' native habitat is F5 (EUNIS code), which is semi-arid and subtropical habitats in pre-saharan Africa. This species has also been found in Southern and Mediterranean Europe, mainly in Spain, France, Italy and Greece. As the African cotton leafworm is prone to cold weather, the species' natural range is limited in the northern regions of Europe such as the United Kingdom. The optimal temperature for the species' reproductive potential is around 25 °C, so areas with lower winter temperatures or fluctuating temperatures show limited species distribution. Studies have shown that temperatures over 40 °C or below 13 °C showed increased in mortality. Combination of high temperature and low humidity are detrimental to the species survival as temperature over 40 °C or below 13 °C tend to increase mortality rate. As a result, S. littoralis resides in regions where temperature fluctuation is rare to feed on variety of host plants, in which the females lay eggs and the larvae primarily grow.

Species distribution mainly occurs through trade when egg or larvae get on the imported ornamentals or crops. Adult moths are often distributed by wind but are also transported by other species. Adult moths fly as well. 

30-10-2023 ADOR CAMPO, VALENCIA - MEDITERRANEAN BROCADE MOTH CATERPILLAR (Spodoptera littoralis)

Larvae body length ranges from 40 to 45 mm. The larvae is usually hairless and varies in color. It has been noted that new born larvae has grayish or dark-green body color whereas the developed larvae has brownish or yellowish body color. Dark and light longitudinal bands along with two dark semi-circular spots on the back are noted characteristics of the larvae. The newly hatched larvae up to third-instar mainly feed on the lower side of the leaves but the later instar larvae feed on both sides. S. littoralis larvae in general are known to feed in the dark. It also has been observed that larvae up to their third and fourth-instar usually remain in their host plant but fifth and sixth-instar larvae leave the host plant during the day and climb back up at night.

The pupa is around 20 mm long and cylindrical in shape. Initially, the pupa is green colored with reddish abdomen but it turns reddish-brown within few hours. Pupation usually occurs 3–5 cm deep in the solid ground under soil. The duration of pupation is around 5–6 hours