SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'bc80e4931821f4fc254dd3543936aaed725fef02fbb30d2efc1821ffeddc74b8' 
  AND token = 'Fb2rWDS+grx6qunuty6veU3sruTp4dDN7HMU1ZSY8Ag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}