Distribution and oviposition characteristics of Orosanga japonica Melichar (Hemiptera: Ricaniidae) in Guilan province, Iran

This study aimed to investigate the oviposition behavior, distribution, and host plants of Orosanga japonica (Hemiptera: Ricaniidae) in Guilan province, Iran. Random sampling was conducted across various locations within Guilan province. Adult insects typically emerge in late July and deposit their eggs from early August to mid-September. This species prefers laying eggs on young shoots and leaf midribs of various plants, from annual herbaceous species to shrubs. This oviposition behavior can lead to stem desiccation. Additionally, the females’ oviposition behavior, sap-sucking activities on stems, and the potential transmission of pathogenic fungi can cause substantial damage to host plants. This research provides information regarding the distribution of pest egg masses across several host plants. Our findings revealed that the mean number of egg masses per twig was higher on chinaberry, averaging 13.75, than on bitter orange, elm trees, and mulberry. The longest average egg mass length, measuring 16.1 mm, was observed on mulberry. Furthermore, this study confirmed the presence of O. japonica in 13 cities within Guilan province, including Rasht, Anzali, Amlash, Astaneh, Lahijan, Langroud, Rezvanshahr, Rudsar, Rudbar, Sowme’eh Sara, Siahkal, Shaft, and Fouman. The insect was predominantly found infesting kiwi, tea, beans, corn, eggplants, peppers, elm leaf blackberries, chinaberries, mulberries, Japanese spindles, cucumbers, citrus plants, fig-trees, rice, cabbage, and grapes.