SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fe04465da0c9cbd24092945a073bf31597ad51bd9bdd3f1f9804a03c9010287' 
  AND token = 'YsnbQhJesPgTZ+yofobMa9N8dZEgsu9NdkYsLrrHCO4=' 
  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"
    }
  }
}