New studies utilizing shared DNA barcodes and images contributed by citizen scientists have shed light on the introduction and distribution of a biological control agent aimed at managing the invasive shrub Lantana camara.
Recent research led by CABI, incorporating publicly available DNA barcodes and images from citizen science, has unveiled insights into the introduction and spread of a biological control agent targeting the widely invasive shrub Lantana camara.
Lantana camara was initially brought in as an ornamental plant in tropical and subtropical regions, but has now become widespread in the Old World, invading areas like woodlands, forests, orchards, grasslands, and other disturbed zones, thereby displacing valuable native flora.
Dr. Matthew Cock, an Emeritus Fellow at CABI, along with his colleagues, utilized DNA barcodes from the Barcode of Life Data System (BOLD) and citizen science images from the platforms iNaturalist and Afromoths to identify the presence of the biological control agent Orphanostigma haemorrhoidalis (Guenée) (Lepidoptera, Crambidae)—which targets L. camara—in regions where it had not been previously documented.
This study represents the first instance of combining publicly available DNA barcodes with citizen science visual evidence to evaluate the establishment and spread of an introduced pest control agent, O. haemorrhoidalis, while also confirming historical distribution records found in existing literature.
Discovery of Two Genetically Distinct Populations of O. haemorrhoidalis
Dr. Cock and his colleagues from Australia’s Department of Agriculture, Fisheries and Forestry, the US Department of Agriculture (USDA), and MIA Consulting identified two genetically distinct indigenous populations of O. haemorrhoidalis in the Americas: one located in the southeastern United States and the other prevalent throughout the broader Neotropics.
These populations were introduced to various global regions, leading to their subsequent spread.
The researchers, whose findings were published in the journal CABI Agriculture and Bioscience, clarified through DNA barcoding from BOLD that the population originating from Florida has successfully established itself in Hawai’i, Australia, and Fiji, while the Trinidad population has spread to parts of mainland Africa (including new sightings in Cameroon, Nigeria, and Ghana), Madagascar, Mauritius, and La Réunion.
New country sightings for O. haemorrhoidalis were documented using images from iNaturalist in Eswatini, Kenya, and Mozambique, as well as from Afromoths for Tanzania.
Evidence of O. haemorrhoidalis Presence in its Introduced Range and Beyond
Dr. Cock affirmed, “The DNA barcodes shared by scientists on BOLD, along with the images contributed by citizen scientists on iNaturalist, verify the presence of O. haemorrhoidalis across much of its introduced range and in several regions where it had not been previously recorded.”
He noted that using unique Barcode Index Numbers (BINs) to categorize similar DNA barcodes has allowed the tracking of the introductions of O. haemorrhoidalis from both Florida and Trinidad as separate entities.
Dr. Cock concluded, “Based on our findings, we determine that Orphanostigma haemorrhoidalis from Trinidad has become widespread in Africa and the Mascarenes and is likely to continue spreading throughout sub-Saharan Africa where Lantana exists.
“The strain from Florida has established itself in Hawai’i, Australia, and Fiji, and we believe it is also present on Norfolk Island and in other Pacific nations where it is known to inhabit (including Federated States of Micronesia, Niue, Tonga, and Vanuatu). Evidence suggests this is the only BIN linked to introductions into Hawai’i and the ensuing spread from there.”
In 2022, CABI scientists contributed to another study published in the journal Plant-Environment Interactions, demonstrating that L. camara reduced maize growth by 29% in East Usambara, Tanzania.
The goal was to enhance understanding of both immediate and long-term effects, as well as the direct and indirect impacts of L. camara for better management of affected agricultural lands.
An Online Community Sharing Biodiversity Information
iNaturalist functions as an online community where individuals exchange biodiversity information, helping one another learn more about nature. It also serves as a collaborative species identification platform and a tool for documenting organism occurrences.
Users can record their observations, request help with identifications, collaborate for shared goals, or access data collected by the iNaturalist community.
Afromoths offers a comprehensive online database of Afrotropical moth species (Lepidoptera), updated with the latest insights gathered from over 10,000 published sources and studies.
The primary aim of this searchable website is to provide global users with access to all pertinent information about every known Afrotropical moth species.
