title: Occurrence of Panagrellus (Rhabditida: Panagrolaimidae) Nematodes in a Morphologically Aberrant Adult Specimen of Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae).
abstract: An aberrant specimen of Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) also known as red palm weevil (RPW), the most economically important insect pest of palms in the world, was found among a batch of conspecifics reared for research purposes. A morphological analysis of this weevil revealed the presence of nematodes associated with a structured cuticle defect of the thorax. These nematodes were not able to be cultured, but were characterized by molecular analysis using 28S and 18S ribosomal DNA and shown to belong to the family Panagrolaimidae (Rhabditida), within a clade of Panagrellus. While most nematodes in the insect were juveniles, a single male adult was partially characterized by light microscopy. Morphometrics showed similarities to a species described from Germany. Excluding the entomopathogenic nematodes (EPN), only five other genera of entomophilic or saprophytic rhabditid nematodes are associated with this weevil. This is the first report of panagrolaimid nematodes associated with this invasive pest. Possible mechanisms of nematode-insect association are discussed.
authors.affiliation: Council for Agricultural Research and Economics, Agrobiology and Pedology Research Centre (CRA-ABP), Via Lanciola 12/A, Cascine del Riccio, 50125 Florence, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Camerota
authors.affiliation: Council for Agricultural Research and Economics, Agrobiology and Pedology Research Centre (CRA-ABP), Via Lanciola 12/A, Cascine del Riccio, 50125 Florence, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Mazza
authors.affiliation: Nematology Laboratory, USDA, ARS, Henry A. Wallace Beltsville Agricultural Research Center, Bldg. 010A, Room 110, Beltsville, MD 20705-2350.
authors.forename: Lynn K
authors.initials: LK
authors.lastname: Carta
authors.affiliation: Council for Agricultural Research and Economics, Agrobiology and Pedology Research Centre (CRA-ABP), Via Lanciola 12/A, Cascine del Riccio, 50125 Florence, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Paoli
authors.affiliation: Council for Agricultural Research and Economics, Agrobiology and Pedology Research Centre (CRA-ABP), Via Lanciola 12/A, Cascine del Riccio, 50125 Florence, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Torrini
authors.affiliation: Council for Agricultural Research and Economics, Agrobiology and Pedology Research Centre (CRA-ABP), Via Lanciola 12/A, Cascine del Riccio, 50125 Florence, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Benvenuti
authors.affiliation: Council for Agricultural Research and Economics, Agrobiology and Pedology Research Centre (CRA-ABP), Via Lanciola 12/A, Cascine del Riccio, 50125 Florence, Italy.
authors.forename: Beatrice
authors.initials: B
authors.lastname: Carletti
authors.affiliation: Council for Agricultural Research and Economics, Agrobiology and Pedology Research Centre (CRA-ABP), Via Lanciola 12/A, Cascine del Riccio, 50125 Florence, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Francardi
authors.affiliation: Council for Agricultural Research and Economics, Agrobiology and Pedology Research Centre (CRA-ABP), Via Lanciola 12/A, Cascine del Riccio, 50125 Florence, Italy.
authors.forename: Pio Federico
authors.initials: PF
authors.lastname: Roversi
keywords: insect thorax defect; invasive species; nematode phoresy; physiological ecology; saprophagous nematode; sour paste nematode