The potential evolutionary impact of invasive balloon vines on native soapberry bugs in South Africa

By

Foster, Jarryd
Ellis, Allan
Foxcroft, Llewellyn
Carroll, Scott
Le Roux, Johannes J.

Type

Article

Date of Publication

2019

Original Publication

NeoBiota : advancing research on alien species and biological invasions

Volume

49

Pages

19-35

Subjects

Balloon vine , Cardiospermum , invasive species , Kruger National Park , Leptocoris , rapid evolution , soapberry bug

Contributed by

Pensoft Publishers

Language

English

Published by

Sophia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/neobiota.49.34245

 

Abstract

Following their establishment in new communities, invasive species may cause evolutionary changes in resident native species. This is clearly true for phytophagous insects, which may adapt rapidly when utilising abundant and widespread introduced hosts. The balloon vines Cardiospermumhalicacabum and C.grandiflorum were introduced to South Africa approximately 100 years ago and are classified as minor and major weeds, respectively. Here we assess the potential evolutionary impact of these vines on native Leptocoris soapberry bug populations in Kruger National Park (KNP), using phylogenetic and morphometric analyses. We found that soapberry bugs associated with C.halicacabum are genetically and morphologically distinct from those associated with C.grandiflorum. This suggests that native soapberry bugs in KNP exhibit some degree of host preference, indicating that these vines may have had significant evolutionary consequences for these insects. The proboscis length of soapberry bugs feeding on C.halicacabum closely matched fruit size, often being longer than fruit size at the population level. These soapberry bugs are therefore well-suited to feeding on this introduced plant species.