Characteristics of Insect Damage in Propagules of Red Mangrove (Rhizophora mangle) from the Gulf of Mexico Coast

Abstract

Several species of insects have been found in propagules of species of mangrove forest, but Coccotrypes rhizophorae (Hopkins) (Coleoptera: Curculionidae) has been recorded as one of the main pest of Rhizophora mangle (L.) (Malpighiales: Rhizophoraceae). While the species of mangrove is common in the Gulf of Mexico, the insect fauna associated with its propagules and characteristics of the damage they cause are unknown. This study evaluated the relationship between the presence of insects and damage characteristics in R. mangle propagules. Eleven mangrove forest sites in seven municipalities of the state of Veracruz (Mexico) were sampled, and 10 R. mangle propagules were collected from each site (110 in total). We found 192 individual insects of Coleoptera, Diptera, Hymenoptera, and Lepidoptera at different stages of development in the propagules; Coleoptera was the most abundant order (64.3%). Qualitative characteristics such as perforations and galleries were not always associated with the presence of insects. However, other damage characteristics such as perforation size and gallery volume were significantly related to insect presence. Gallery volume, estimated as a measure of the intensity of tissue removal, was significantly greater when C. rhizophorae shared the gallery with other species of insects than when the beetle or other insects were found alone in the propagule. The results showed that R. mangle propagules could maintain colonization dynamics in insects of different orders, consuming tissue that jeopardized the survival and establishment of propagules. The damage can increase under stress in R. mangle, caused by environmental factor generating potential damage to tropical sentinel ecosystems that can eventually become irreversible.