Search

Despite Arthropoda being a major animal taxon, it is underrepresented in South American scientific publications. Here, we present the results of a bibliometric analysis of published studies on insects and arachnids in Colombia to understand the general patterns of knowledge of both taxa across this megadiverse country. We compiled 3119 studies on insects and 353 on arachnids published between 1918 and 2019 in more than 600 journals. Research on both insects and arachnids reflects the effort done by researchers working in Colombian institutions, but because publications are mainly domestic, their international impact is limited. The studies included 19 taxonomic orders of insects and 72 families of arachnids with a bias toward a few well-studied taxa like Diptera, Lepidoptera, Hymenoptera, Araneidae, and Salticidae, while the majority of taxa are understudied. The geographic coverage of the studies was broad and includes Colombia's 32 departments, but their distribution was heterogeneous being the Andean region the most studied, while the Caribbean and Orinoquia regions could be considered knowledge gaps. Considering our analysis, we give recommendations to expand and advance the knowledge of Colombian insects and arachnids, a major scientific enterprise in which collaboration among researchers from different institutions is needed. [ABSTRACT FROM AUTHOR]

Very little is known about the biology of larval odonates from the Neotropical region, and in particular there are no data on behavioral changes during ontogeny and growth ratios, though both are crucial to understanding the dynamics of Odonata communities. Here we study growth ratio, development patterns and behavior of Rhionaeschna marchali larvae. We characterized larval instars using morphometric variables and describe their general behavior. Larvae were obtained from eggs laid by two females in the laboratory. They were maintained in individual containers until their emergence or death. Larvae hatched between 26 and 30 days after laying, and total development time was 340.5 (±5.9) days, with 15 instars. Growth ratios between successive instars averaged 1.12 for head width, 1.25 for head length, 1.20 for antenna length, 1.76 for forewing-pad length, 1.74 for hind wing-pad length, 1.19 for metafemur length and 1.22 for total length. Rhionaeschna marchali larvae spent most time “resting” and “grooming”. As size increased, larvae became more active and time “resting” decreased. The behavior “upwards abdomen bend” showed a decreasing trend with size, while “body bend downwards” became more common with increasing size. The high altitude (2600 m) of the region acts as a limiting factor for growth, and therefore this species completes one generation per year, similar to many temperate species. [ABSTRACT FROM AUTHOR]