Two newly introduced Heteroptera (Insecta: Hemiptera) species in Colombia: Brachyplatys subaenus (Plataspidae) and Thaumastocoris peregrinus (Thaumastocoridae)

The introduction of alien species can carry negative consequences to the areas in which they appear. Early detection of introduced species is key if management practices are to be effectively implemented. Here, based on specimens from collections and citizen science observations, we document the recent introduction of two alien Heteroptera (Insecta: Hemiptera) species in Colombia: Brachyplatys subaenus (Westwood, 1837) (Plataspidae) and Thaumastocoris peregrinus Carpintero & Dellapé, 2006 (Thaumastocoridae). Brachyplatys subaenus was found in two localities (Bolívar and Valle del Cauca), whereas T. peregrinus was found in a single locality (Bogotá) so far. Future research activities should establish the geographic range of these species, as well as document their host plant associations, in Colombia.


INTRODUCTION
Exotic invasive species are costly to society (Simberloff et al., 2013), and among these, insect species are considered the most expensive (Diagne et al., 2021). Among all living organisms insects constitute about 40% of all known species (Adler & Foottit, 2017;Stork, 2018), thus it is not surprising that the most common group of introduced animals found worldwide are insects (Liebhold et al., 2018). Because of the ample negative societal impacts of alien species, ranging from ecosystem function to human well-being (Pyšek et al., 2020), early detection is key to implement appropriate management practices Simberloff et al., 2013).
Here, I document two introduced species in Colombia that possess the potential to become invasive in agricultural settings, highlighting the importance of an early detection to better implement management strategies.

MATERIAL AND METHODS
Examined specimens are deposited at the Colección Entomológica, Museo Javeriano de Historia Natural, Pontificia Universidad Javeriana, Bogotá, Colombia (MPUJ_ENT). In addition, some observations uploaded to the citizen science initiative iNaturalist (https://www. inaturalist.org), were used to complement the distribution documented from specimens. In this case, the observations were all identified or corroborated by me. Images of specimens were carried out using a dissecting scope Nikon SMZ1270 equipped with a Nikon D5300 digital camera.

Brachyplatys subaenus (Westwood, 1837) (Fig. 1)
Remarks: The highest diversity of Plataspidae is found in tropical and subtropical regions of the Eastern Hemisphere, with a few species widely distributed in the temperate Palearctic (Schuh & Weirauch, 2020). The first species of Plataspidae recorded from the Western Hemisphere was Megacopta cribraria (Fabricius, 1798), discovered in the USA in 2009 (Eger et al., 2010). This species is found from China (temperate and tropical) to tropical Asia and Australia, and it is associated mainly with kudzu Pueraria montana var. lobata (Willd.) Maesen & Almeida, and which has been considered recently a pest of soybeans Glycine max (L.) (Ruberson et al., 2013). A second plataspid found in the Western Hemisphere is B. subaenus, which was first discovered in Panama in 2012, being also the first record from the Neotropical region (Aiello et al., 2016). This species was initially misidentified in Panama as B. vahlii (Fabricius, 1787) but later correctly identified as B. subaenus by Rédei (2016). Rédei (2016) provided diagnostic characters that help identify this species and differentiate it from B. vahlii. Plataspidae species feed primarily on legumes (Schaefer, 1988), being B. subaenus no exception, which is known to feed on a variety of legumes species in its native range in Indomalaya, although other plant species in various families have also been recorded as host plants (Rédei, 2016). In the Neotropical countries in which B. subaenus has been found, it has been recorded on the following Fabaceae host plants: the cultivated Cajanus cajan (L.) Mill sp., Glycine max, and Mucuna pruriens (L.) DC (Aiello et al., 2016;Añino et al., 2018Añino et al., , 2020Carmona-Ríos, 2019;Perez-Gelabert et al., 2019); the endemic and cultivated Phaseolus vulgaris L. (Perez-Gelabert et al., 2019), Gliricidia sepium (Jacq.) Kunth ex Walp. (Añino et al., 2018;Carmona-Ríos, 2019); and the endemic Leptolobium panamense (Benth.) Sch.Rodr. & A.M.G.Azevedo (Aiello et al., 2016). It has also been found on the following non-Fabaceae host species: Bactris gasipaes Kunth, Schefflera actinophylla (Endl.) Harms (Aiello et al., 2016), and Zea mays L. (Añino et al., 2020). In Colombia, B. subaenus has no recorded host plant species.
Distribution: Known in the Neotropical region from Costa Rica (Carmona-Ríos, 2019), Panama (Añino et al., 2018), Dominican Republic (Perez-Gelabert et al., 2019), Guadeloupe (Anonymous, 2020), and Ecuador (Añino et al., 2020). Additional localities can be found on iNaturalist (http://www.inaturalist.org) for some of these countries. Newly recorded from Colombia from two localities, in Cali (Valle del Cauca) and Isla Grande (Bolívar).  . 2) Remarks: Thaumastocoris peregrinus was described based on specimens collected in Argentina but acknowledging its Australian origin (Carpintero & Dellapé, 2006). Noack & Coviella (2006) simultaneously reported a Thaumastocoris species from Buenos Aires (Argentina) but misidentified it as T. australicus Kirkaldy, which was later identified as T. peregrinus (Noack et al., 2011). Carpintero & Dellapé (2006) also assigned to T. peregrinus specimens found in South Africa but also misidentified as T. australicus. The taxonomy of this Australian endemic genus Thaumastocoris was clarified by Noack et al. (2011), in which they provide a revised diagnosis and comparative notes for T. peregrinus. Most of the host plant associations of Thaumastocoris are with species of Myrtaceae, in which nearly all species are associated with species of Eucalyptus L'Hér. (Noack et al., 2011). Thaumastocoris peregrinus has been documented to feed on one species of Corymbia K.D. Hill & L.A.S. Johnson and at least 13 species of Eucalyptus (Jacobs & Neser, 2005;Noack & Coviella, 2006;Noack et al., 2011;Nascimento-Machado et al., 2019). The Colombian examined specimens were collected in an unidentified species of Eucalyptus. In all places in which T. peregrinus has been accidentally introduced, it has caused damages to ornamental or cultivated Eucalyptus species (Machado et al., 2020), and it is likely that biological control might be the best management option (Nadel & Noack, 2012;Souza et al., 2012). Pinzón-Florián (2020)    Portugal, Spain, Albania, Greece) (Carpintero & Dellapé, 2006;Noack et al., 2011;Nascimento-Machado et al., 2019). Newly recorded from Colombia from a single locality in the high Andes (Bogotá).

DISCUSSION
In Colombia, B. subaenus is only known from two localities, one in the Cauca valley (Cali) and the other in the Caribbean coast (Isla Grande). In all the other Neotropical countries from Central and South America where it has been recorded, the localities are close to the seashore (Aiello et al., 2016;Añino et al., 2018Añino et al., , 2020Carmona-Ríos, 2019). In Colombia, the Caribbean locality is very close to Cartagena, a coastal touristic city receiving people from all over the world, mostly from cruises. This locality is also very close (less than 100 km) to Barranquilla, a city with the main port and with the most important industrial facilities on the Colombian Caribbean coast. Therefore, it is likely that B. subaenus might have arrived from another place in the Caribbean via either commercial or touristic routes. This also means, that given the proximity of the documented locality to potential areas of easy dispersion by human means, it is likely that B. subaenus would be soon found in other localities in Colombia. On the other hand, although Cali is in an inter-Andean valley far away from the seashore, it is the main city connecting the Buenaventura port in the Pacific coast to the rest of the cities in Colombia. Therefore, it seems plausible that individuals of B. subaenus found in Cali, might have ar- rived there from Buenaventura trough sea commerce, and dispersed via terrestrial transportation to the interior of the country.
Thaumastocoris peregrinus, although widely distributed now in the Western Hemisphere, has not been recorded before from northern South America. It is intriguing that the locality in which it was found was in the middle of this large city in the high Andes. This could mean either that T. peregrinus arrived through commerce goods directly to Bogotá, or that it arrived at some lowland locality, and it later dispersed into the city. The first scenario would imply a contained distribution, whereas the second one would imply a much larger distribution already for T. peregrinus.
For both B. subaenus and T. peregrinus it is thus very important to document their present distribution and host plant associations in Colombia. An analysis of their geographic distribution will help to better understand the biology and development of each species regarding abiotic variables such as temperature or rainfall. Host plant associations will allow to, first, evaluate if these alien species are causing economic losses to cultivated crops, and second, to assess the extent of plant species serving as secondary hosts. This baseline information would be important to later implement adequate management practices for both species. Finding B. subaenus and T. peregrinus in Colombia for the first time highlights the importance of accurate taxonomic information derived from natural history collections and citizen science initiatives.

ACKNOWLEDGMENTS
I thank Wolfgang Rabitsch (University of Vienna) and two anonymous reviewers for their criticism that improved the manuscript. This paper is a contribution to the project "Actividades docentes y de investigación como apoyo al conocimiento de la biodiversidad colombiana" ID PPTA 00006416 to DF of the Pontificia Universidad Javeriana.

CONFLICT OF INTEREST
The author declares that he has no conflict of interest and confirms that there are no disputes over the ownership of the data presented, and all contributions have been attributed appropriately.