SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74892158049adb50c95bd8725bb6c569dac820f059c0393b153b2ace2f19bde7' 
  AND token = 'jazaWmBTfQO2q/qCRtWrRHZ0urBJrVN3C+A0kZidOsc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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