ABSTRACT
Abstract: Galling insects are specialist herbivorous that have the ability of manipulating plant tissue to form complex biological structures called galls. Even though different organisms have the ability to induce galls in plants, insect galls have the highest degree of structural complexity. The main goal of this study was to obtain a preliminary systematic record of plant gall morphotypes from the Guanacaste Conservation Area in Costa Rica and integrate the information into a biological database. Plant gall morphotypes were recorded, characterized and deposited into a specialized herbarium established as a reference for the inventory. Moreover, organisms associated with gall morphotypes were included in the inventory when it was possible to obtain and identify them. Galls were collected in the rainy season over a period of three years. In total, we recorded forty-four families, seventy genera, and eighty-seven host plant species. One hundred thirty-one morphotypes of plant galls were identified in the Guanacaste Conservation Area. The family with the highest number of gall morphotypes was Fabaceae (8.4%). Leaves were the organ with the largest number of galls (71%), followed by stems (17.6%), and apical buds (6.9%). The predominant gall shape was globular (25.2%), followed by discoid (18.3%). Fifty-nine percent of the galls had a glabrous texture, which was most common on leaves, with 77%. One hundred twenty of our field records (91.6%) of plant galls were new morphotypes not only for Costa Rica but also the world. As a consequence of this research and considering the prospect of future increases in new gall records (and associated organisms), we proposed having the biological entities resulting from the inventory placed in a cecidiarium. This repository represents a standardized and comprehensive way to manage the data and biological materials associated with the plant galls. We also suggest a nomenclature for standardizing gall morphotype registries and identifications. This work is the first and most detailed inventory of plant galls carried out thus far in the Guanacaste Conservation Area.
Resumo: Os insetos galhadores são herbívoros especializados, que têm a habilidade de manipular os tecidos vegetais, formando uma complexa estrutura biológica. Diferentes organismos têm a capacidade de induzir galhas, porém as de insetos têm maior grau de complexidade estrutural. O principal objetivo desse estudo foi realizar um levantamento sistemático preliminar das galhas de insetos na Área de Conservação Guanacaste, na Costa Rica, e inserir as informações em uma base de dados biológicos. Os morfotipos de galhas foram registrados, caraterizados e depositados em um herbário estabelecido como base de referência deste inventário. Além disso, quando foi possível obter e identificar os organismos associados a cada morfotipo de galha, eles foram incluídos no inventário. As amostras de galhas foram coletadas na estação chuvosa, durante três anos. No total, foram registradas 44 famílias, 70 gêneros e 87 espécies de plantas hospedeiras. Cento e trinta e um morfotipos de galhas foram identificados na Área de Conservação de Guanacaste. A família com o maior número de morfotipos de galhas foi Fabaceae (8.4%). Os órgãos vegetais com o maior número de galhas foram as folhas (71,0%), seguidas dos caules (17,6%), e das gemas apicais com 6,9%. A forma predominante das galhas foi globoide (25,2%), seguida da lenticular (18,3%) e 59% das galhas apresentaram textura glabra, observada mais frequentemente folhas (77%). Cento e vinte morfotipos de galhas (91.6%) representaram novos registros não só na Costa Rica como também no mundo. Como consequência desta pesquisa e considerando as perspectivas de aumentos futuros de novos registros de galhas (e organismos associados), nós propomos que as entidades biológicas resultantes deste inventário sejam depositadas em um cecidiário. Este repositório representa uma maneira padronizada e abrangente de gerenciar e integrar os dados e os materiais biológicos associados às galhas das plantas. Também sugerimos uma terminologia para padronizar os registros e identificações dos morfotipos de galhas. Este inventário de galhas em plantas é o primeiro e o mais detalhado já realizado na Área de Conservação Guanacaste.
ABSTRACT
There has been an increasing number of inventories of gall-inducing arthropods in the Neotropics. Nonetheless, very few inventories have been carried out in areas where the flora is well documented, and records of galls from herbaria and sites outside the study area have seldom been utilized. In this study we provide a checklist of the native vascular plants of a 345 ha forest reserve in the Caribbean lowlands of Costa Rica and document which of these plants were found to harbor galls. The gall surveys were carried out between November 2013 and December 2016. We also cross-checked our plant list with the previous gall records from elsewhere in the country and searched for galls on herbarium specimens of dicots reported from the reserve. In total, we recorded 143 families and 1174 plant species, of which 401 were hosts of galls. Plant hosts of galls were found in the following non-mutually exclusive categories: 209 in our field sampling, 257 from previous records, and 158 in herbarium specimens. Of our field records of galls, 77 were new for the country, 77 were also found in the herbarium and 110 had been previously recorded in the country. Herbarium specimens and previous records are good indicators of potential gall hosts but around one quarter (40/158) of the gall records in the herbarium were ambiguous as to whether the tissue alteration was a gall or not. Plant family size was related to number of gall hosts, but most dicot families have similar proportions of gall host species. We concluded that more than a third of the native plants in the reserve are gall hosts, but this number increased to 44.93 % when only dicots were considered. Our results demonstrate the utility of providing complete plant inventories when conducting gall inventories, and of using herbarium specimens and previous galls studies to infer gall diversity in a specific area.
Los estudios relacionados con la diversidad de insectos inductores de agallas han venido aumentando en el Neotrópico. Sin embargo, pocos inventarios se han realizado en sitios donde la flora está bien documentada y los registros previos de agallas, así como información disponible de herbario, han sido subutilizados. En este estudio brindamos un inventario de las plantas nativas en una reserva de 345 ha ubicada en las tierras bajas del Caribe costarricense y documentamos cuales de estas son hospederas de agallas. El muestreo de agallas se llevó a cabo entre noviembre del 2013 y diciembre del 2016. Así mismo, comparamos nuestra lista de plantas con los registros previos de agallas encontradas en el resto del país y examinamos en herbario todas las dicotiledóneas registradas en la reserva en busca de agallas. En total, encontramos 143 familias y 1 174 especies de plantas de las cuales 401 especies fueron hospederas de agallas. Estas fueron encontradas de las siguientes categorías no mutuamente exclusivas: 209 mediante colectas de campo, 257 a partir de registros previos y 158 en material de herbario. De las plantas con agallas encontradas en el campo 77 corresponden a registros nuevos para el país, 77 fueron halladas también en herbario y 110 habían sido reportadas anteriormente en el país. El material de herbario y los registros previos demostraron ser buenos indicadores de las potenciales especies de plantas hospederas de agallas, sin embargo, alrededor de una cuarta parte (40/158) de los registros de agallas en herbario son ambiguos (difíciles de determinar si son agallas o no). El tamaño de la familia de las plantas está relacionado con la diversidad de especies de plantas hospederas de agallas, no obstante, la mayoría de las familias de dicotiledóneas tiene una proporción similar de especies hospederas de agallas. Concluimos que al menos un tercio de las especies de plantas nativas de la reserva son hospederas de agallas, pero este número incrementa a 44.93 % cuando solo se consideran las dicotiledóneas. Nuestros resultados demuestran la importancia de proveer inventarios completos de plantas cuando se realizan inventarios de agallas, así como la utilidad de examinar material de herbario y contrastar registros previos para inferir la diversidad de agallas en un sitio.