SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1aa60d7a23f3473498eea6f736aaea25363c805e3beeddcd14da4032196aaa9' 
  AND token = 'XLBKw2/hzMaGGLf5XLpALqjKalOeAxxwLZQrC4FxJWo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}