An ongoing survey for novel phytoplasmas and viruses that affect palms (Arecaceae) is being conducted in Costa Rica along with potential vectors. During that survey, a new species of derbid planthopper (Hemiptera: Fulgoroidea) in the genus Omolicna Fennah was detected from Heredia and Limón State and is here described as Omolicna xavieri sp. n. This new taxon was first found on declining coconut palms (Cocos nucifera) and subsequently on healthy coconut palms in Tortuguero National Park. Also, two additional species of Omolicna, O. brunnea and O. triata, were collected on coconut in the same habitat and represent new country records. There are no previously published records of Omolicna from Costa Rica. Sequence data for the cytochrome c oxidase subunit I (COI) and the 18S ribosomal RNA gene were obtained. In addition, novel 18S primers specific to auchenorrhynchan insects were developed and presented. The molecular data show high pairwise distances between O. xavieri sp. n. and other Omolicna species (24% to 31% and 10% using COI and 18S, respectively). Based on both morphological and sequence data, we erect and briefly describe the new subgenus Agoo for the new species to reflect the observed differences. A checklist of Omolicna species is presented.

Myxia belinda gen. et sp. nov. is established for a new taxon of Cixiidae in the tribe Oecleini collected from palms in Costa Rica. The new taxon was discovered while surveying palms for potential phytoplasma vectors. Placement in a new genus is supported by a 1,383 bp sequence of 18S that differs by 2.77% from Haplaxius, 5.20% from Myndus taffini, and 2.80% from Nymphomyndus caribbea. Intrageneric variation for 18S was found to be approximately 0.5% to 0.6% within Haplaxius. Generic level differences within the Oecleini for COI ranged from 15% to 17% with the novel taxon differing by about 16% from other genera. The new genus is most similar in appearance to Haplaxius but possesses striking sexual dimorphism, and the aedeagus is only partially surrounded by the phallobase (versus entirely enveloped in Haplaxius). The discovery of a novel taxon of cixiid on palms that is similar to Haplaxius is important because of the role that Haplaxius crudus plays in phytoplasma transmission in palm agro- and natural ecosystems.

The 16SrIV-D phytoplasma was first identified in Florida in 2006. Since its discovery, it has spread throughout most of the state. It is most prevalent in the central part of Florida, from Hillsborough County on the west coast to St. Lucie County on the east coast. The 16SrIV-D phytoplasma is the causal agent of lethal bronzing disease (LBD), which is also known as Texas Phoenix palm decline (TPPD). It affects a variety of common and economically important ornamental palm species as well as the native and ecologically important species, Sabal palmetto. It has spread into the southern portions of Florida, where the palm species diversity is higher. The aims of this survey were to document the spread of disease in terms of geographic and host range one decade after its introduction into Florida, and to assess the risk that LBD poses to the nursery and landscaping industries. The survey included samples received from stakeholders throughout the state, covering 18 counties, as well as a systematic sampling of palms at the Fort Lauderdale Research and Education Center (FLREC), where the disease is spreading actively. The findings of this survey resulted in the detection of LBD in eight new counties, including Collier, Hernando, Jefferson, Martin, Miami-Dade, Monroe, Seminole, and St. Johns, and the expansion of LBD into four new host species, Cocos nucifera, Livistona chinensis, Butia capitata, and Carpentaria acuminata. These findings are crucial for stakeholders because they highlight new hosts of 16SrIV-D phytoplasma and the geographic expansion of the disease, indicating that vigilance is needed when surveying declining palms.