SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '48798a31f5f7e2b2af0ebed1bf83ef65a71a689d0769e590342f7f30f441a56c' 
  AND token = '5d1Jj5rkTHKfCBB76k6/dj+e/FXbdRtugAiBcd+fbE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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