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Laurel wilt, a lethal vascular wilt disease caused by the fungus Raffaelea lauricola, affects several tree species in the Lauraceae, including three Persea species. The susceptibility to laurel wilt of two forest tree species native to the southern United States, Persea borbonia and Persea palustris, and avocado, Persea americana cv Waldin, was examined and related to tree physiology and xylem anatomy. Net CO2 assimilation (A), stomatal conductance (gs), leaf chlorophyll index (LCI), leaf chlorophyll fluorescence (Fv/Fm), xylem sap flow, theoretical stem hydraulic conductivity (Kh) and xylem vessel anatomy were assessed in trees of each species that were inoculated with R. lauricola and in control trees. Laurel wilt caused a reduction in A, gs, LCI, Fv/Fm, and blockage of xylem vessels by tyloses formation that negatively impacted Kh, and sap flow in all Persea species. However, disease susceptibility as indicated by canopy wilting and sapwood discoloration was less pronounced in P. americana cv Waldin than in the two forest species. Xylem vessel diameter was significantly smaller in P. borbonia and P. palustris than in P. americana cv Waldin. Differences in laurel wilt susceptibility among species appears to be influenced by physiological and anatomical tree responses.

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The poorly studied Mesoamerican genus Adamsiana Penny, 1996 (Neuroptera: Ithonidae) was considered monotypic for more than 20 years, containing only Adamsiana curoei Penny. However, a second species was recently discovered in the southern region of Guatemala and is described here as Adamsiana alux Ardila-Camacho, Castillo-Argaez & Martinez, sp. nov. A key to the Adamsiana species and a list of the extant New World Ithonidae species are provided. This work emphasizes the necessity for more studies about not only Ithonidae but also all entomological fauna in the Neotropics.

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