SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '597a308c31db6e91b58078a7faec83c473b6f791e94bde981c870e09acd178a6' 
  AND token = 'wXyu7DfOBXqCzEUE44nvUGId4KKhQfS76UuzVjJW4TQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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