SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58fe5c70c9cc5a1390fd93d743200f189612a04f49aca8cd8a452c54f757df3a' 
  AND token = 'BgGMzThif/psKEWeGIPIjn8SzWijqxawAg5dsO8EMoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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