SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7d619b24dc6a22c699f2fb3e1f1bd4f856e62a423eadd9df3bb8a41e78e1a5b' 
  AND token = 'bMwW6jDdGlCUq+5zrXuDHQc+vJaIVvn8mfkgCWq/WNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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