SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bd3db86597489e3b9b13a099a54673703721c6faa91a08cf6c6ac46dab1d7ddf' 
  AND token = 'T2CGUXNJhI89aaprimFeb3olohre+oVVxubBzGeKL8E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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