SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e8318c464073b0de01b2d3c57798603c994f216654869ad38f2148bdd42137e' 
  AND token = '4B03yN6mhzj7eXjVwrD2P+3OLgu1icHOXMxAI6xCFOg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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