SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'daebca034ac41538e8ed017d529cccecbc4a83221035ede28b9f5d481f795217' 
  AND token = 'Qg4UUUadTChQ92gunrbluscOIswC39KE4iUE9YtQLbo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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