SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a892e6a9f412a9fe3ad03f161613d969d3169d7e3da1f69791a01fc6e1adfb5' 
  AND token = 'Zz8c7pMwJFUQ6WqoeBwmXrsepHZ6aHGG5nNyWPCGKTM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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