Tychius semisquamosus

Members of the semisquamosus group can be distinguished from other North American Tychius by host associations with Astragalus species in American groups and with Lotus. T. semisquamosus specifically may be distinguished from T. tectus and T. liljebladi, which are more closely allied to Eurasian relatives and have hosts in Oxytropis and Eurasian groups of Astragalus.

North America. The semisquamosus group appears to have been established in North America prior to the arrival of T. liljebladi and T. tectus.

Feeding habits involve leguminous seeds; host plants include species of Astragalus (American groups) and Lotus.

• Astragalus - host plantAmerican groups of Astragalus
• Lotus - host plant

Seed predator of leguminous plants; may be subject to competitive displacement by T. tectus, which appears to be extending its geographic and host range at the expense of some semisquamosus group members.

• Tychius tectusMore closely allied to Eurasian relatives; has hosts in Oxytropis and Eurasian groups of Astragalus; expanding range at expense of semisquamosus group members
• Tychius liljebladiMore closely allied to Eurasian relatives; has hosts in Oxytropis and Eurasian groups of Astragalus; arrived in North America after semisquamosus group was established
• Tychius lamellosus (synonymized)Formerly described as distinct species, now synonymized with T. semisquamosus
• Tychius squamosus (synonymized)Formerly described as distinct species, now synonymized with T. semisquamosus
• Tychius intermixtus (synonymized)Formerly described as distinct species, now synonymized with T. semisquamosus

• Curculionidae
• seed weevil
• legume feeder
• North America
• Astragalus
• Lotus

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• Catalogue of Life
• North American Tychius: New synonymy and observations on phylogeny and zoogeography (Coleoptera: Curculionidae)