SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ac86f224ef530dde5a99ef440fa461b4f17da19b4d472bbaec35b790b916c16' 
  AND token = 'EwOZWHr23WzbkOjuFWBbNpIEHOozEKbF3EG902eYno4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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