Guinea-Bissau
Insects unique to Guinea-Bissau include two grasshoppers Parga bissauensis (SysTax) and Catantopsilus hintzi (SysTax), a tiger beetle Cylindera gulbenkiana (Zootaxa pdf file), a longhorned beetle Pterolophia consimilis (eol), and two dung beetles Caccophilus (or Caccobius) lateralis (Internet Archive) and Onthophagus androgynus (African Dung Beetles Online). Endemic spiders include a jumping spider Pochyta major (Salticidae of the World) and two wolf spiders Arctosa laccophila (World Spider Catalog) and Lycosa storeniformis (World Spider Catalog).
Vertebrates found only in Guinea-Bissau include a longtail lizard Latastia ornata (Reptile Database) and the Cassine River Worm Lizard Cynisca oligopholis (p. 60 of AMNH
Digital Library 19 MB pdf file).
Vascular plants known solely from Guinea-Bissau include Nesaea santoi (JSTOR) and Pandanus guineabissauensis (JSTOR). Also sometimes recognized as distinct species are Hyphaene santoana (JSTOR) and Commelina gourmaensis (Kew).
For more information on the plants and animals of Guinea-Bissau see the Biodiversity Strategy and Action Plan (CBD pdf file).