SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee3f9ad232ae1012bfb4f67b4132434a43bef6f18c046650f2a42de19a77568e' 
  AND token = 'lUSKYjKhfhmc2rVcqqv7P9zayR3F1V4dI3A7Q7IADN4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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