SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbadbd858154a4fdfcf5ab1db14bc53d98d7aa7289bda9aa77c8f71cd60b2428' 
  AND token = 'LTHfuEG6ZuzzvkazIBWqN8KbsDnEThkcLQMBgQ51Wmw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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