SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '329bdf2b722294e4bf1bffe3046c389c8717528ee761d44e4236d49500512815' 
  AND token = 'IwFcz89x5tuSXfgZ07Bna6wpl8HAhoJwQePTT/68FKg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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