The global distribution of diet breadth in insect herbivores.

Understanding variation in resource specialization is important for progress on issues that include coevolution, community assembly, ecosystem processes, and the latitudinal gradient of species richness. Herbivorous insects are useful models for studying resource specialization, and the interaction between plants and herbivorous insects is one of the most common and consequential ecological associations on the planet. However, uncertainty persists regarding fundamental features of herbivore diet breadth, including its relationship to latitude and plant species richness. Here, we use a global dataset to investigate host range for over 7,500 insect herbivore species covering a wide taxonomic breadth and interacting with more than 2,000 species of plants in 165 families. We ask whether relatively specialized and generalized herbivores represent a dichotomy rather than a continuum from few to many host families and species attacked and whether diet breadth changes with increasing plant species richness toward the tropics. Across geographic regions and taxonomic subsets of the data, we find that the distribution of diet breadth is fit well by a discrete, truncated Pareto power law characterized by the predominance of specialized herbivores and a long, thin tail of more generalized species. Both the taxonomic and phylogenetic distributions of diet breadth shift globally with latitude, consistent with a higher frequency of specialized insects in tropical regions. We also find that more diverse lineages of plants support assemblages of relatively more specialized herbivores and that the global distribution of plant diversity contributes to but does not fully explain the latitudinal gradient in insect herbivore specialization.

New leafhopper species of Jikradia from Mesoamerica with new records, revised key to species, distribution, origin, and checklist (Hemiptera: Cicadellidae: Coelidiinae: Teruliini).

The following four new species of leafhoppers are described and illustrated: Jikradia dentata n. sp. and J. trispinata n. sp. from Guatemala, J. variabilis n. sp. from Belize, and J. exilis n. sp. from Costa Rica. Jikradia basipendula Nielson and J. krameri Nielson are new records for Guatemala. Belize is a new record for the genus. A record of the first introduction of the genus in the Old World is reviewed. A revised key to the known species is provided with a review of its possible origin. A checklist of all known species is also given.

New leafhopper species of Jikradia from Mesoamerica with new records, revised key to species, distribution, origin, and checklist (Hemiptera: Cicadellidae: Coelidiinae: Teruliini)

The following four new species of leafhoppers are described and illustrated: Jikradia dentata n. sp. and J. trispinata n. sp. from Guatemala, J. variabilis n. sp. from Belize, and J. exilis n. sp. from Costa Rica. Jikradia basipendula Nielson and J. krameri Nielson are new records for Guatemala. Belize is a new record for the genus. A record of the first introduction of the genus in the Old World is reviewed. A revised key to the known species is provided with a review of its possible origin. A checklist of all known species is also given. Rev. Biol. Trop. 62 (4): 1375-1383. Epub 2014 December 01.

Las siguientes cuatro nuevas especies de chicharritas son descritas e ilustradas: Jikradia dentata n. sp. y J. trispinata n. sp. de Guatemala, J. variabilis n. sp. de Belice, y J. exilis n. sp. de Costa Rica. Jikradia basipendula Nielson y J. krameri Nielson son nuevas especies reportadas para Guatemala. El género Jikradia es un nuevo registro para Belice. Un registro de la primera introducción del género en el Viejo Continente es revisado. Se presenta una clave revisada de las nuevas especies con una revisión de su posible origen. También se presenta una lista revisada de todas las especies conocidas.