Siamastogenius

{{short description|Genus of beetles}}

{{Italic title}}

{{Taxobox

| name = Siamastogenius cyaneus

| regnum = Animalia

| phylum = Arthropoda

| classis = Insecta

| ordo = Coleoptera

| subordo = Polyphaga

| superfamilia = Buprestoidea

| familia = Buprestidae

| genus = Siamastogenius

| genus_authority = Toyama, 1983

| species = S. cyaneus

| binomial = Siamastogenius cyaneus

| binomial_authority = Toyama, 1983

}}

Siamastogenius cyaneus is a species of beetles in the family Buprestidae, the only species in the genus Siamastogenius.{{cite web |url=https://cerambycids.com/Buprestidae/WorldCat/Genera/Siamastogenius.htm |title=Genus Siamastogenius |author=Bellamy, C. L. |date=2013 |work=A Checklist of World Buprestoidea |accessdate=7 Sep 2021}}