SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'de960356120241aae0c776548f1b8051e65cae9dc4547a442c61e8da102ab3a3' 
  AND token = 'gAdBUZQSrf6vtYWs28TPRf38A2bDILZkD0caQxaUNkI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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