SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4cc83f864c27223af63d5b48b8cc80afa6eea232a55e2b1e2df36729ca1eed05' 
  AND token = 'C+QtSLGvGxtDgXAKdpkxzDDRj9Cv2oPqjPIAWYu7ti8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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