SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7a38e3ef6e258066d9357d1aab207f503d03d197b55ff5b733025d94a4bdbdfb' 
  AND token = 'nEOXPkpOLg6kqVzwW6H+dMQUqppq6Yvw9gL1pLmnJ3w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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