SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7344ededaaa33f2c98a230f709f4fd1eb20a02cf05f534529b64fdf49ceae02b' 
  AND token = '0DxUKhNgqSsAY6KQoAGgdDhQEYvHGIit7ytWUgu7foY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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