SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b51dd018a5c2773778eda77ce3c3e10f95c85528da177022360bb08c973efec' 
  AND token = 'CCBFyGkT9dCi6A6lkkCeUU02AHijpmpwh7r7c0VQJMM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}