SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '68fd5b6267d7326c411d40931f81a532127edc4f34d182ff825e00d140a96613' 
  AND token = 'YNTj9nokYyMddHOxNN07d4ucHaJ5dsmfIU6JZVed/1U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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