SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1889674ffb32fbf34146fa7d35bbcfdeb50d93759beb232194a3fd1c6022e94a' 
  AND token = '/NqAym59f4HSqKiO7jEpN1cCQgt9q4cK8FVQBonBlmw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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