Tribulus-terrestris
Guides
Microlarinus
puncturevine seed weevils
Microlarinus is a genus of weevils (Curculionidae) comprising at least two species, M. lareynii and M. lypriformis, specialized on puncturevine (Tribulus terrestris). Both species have been introduced to North America as classical biological control agents. M. lareynii attacks seeds while M. lypriformis feeds on stems. Despite their potential, establishment and impact have been variable due to climatic and biological mismatches with host populations.
Microlarinus lareynii
Puncturevine seed weevil
Microlarinus lareynii is a seed-feeding weevil in the family Curculionidae, native to the Mediterranean region and India. It was introduced to North America in the early 1960s as a biological control agent for puncturevine (Tribulus terrestris), an invasive weed. The species exhibits strong host specificity, with larvae developing exclusively within the seeds of its target host plant. Despite its potential for high reproductive output, field success in controlling weed populations has been variable due to climatic and biological mismatches with the host plant.
Microlarinus lypriformis
Puncture vine stem weevil
Microlarinus lypriformis is a stem-boring weevil (Coleoptera: Curculionidae) introduced to North America as a biological control agent for puncturevine (Tribulus terrestris). Females oviposit into the stems of this host plant, and larvae feed internally on the pith, causing stem damage and plant mortality. Adults emerge through exit holes bored in the stem. The species has been used in combination with the seed-feeding weevil Microlarinus lareynii in biocontrol programs in the United States and Canada.