SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '624210afbf48ce8d73aed90c04ca050429459c67e933fff74bac9df8252adfcf' 
  AND token = 'opYl6xGKTRaExG5a/LgqYaOel1tn+C88H3jrI56sIJY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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