SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd1988fbaeb1baaa815cf741fbb06f0289cfb3f3d17956c3f905fe772d7c1f501' 
  AND token = 'WyHREjH8tpnaSAmh+8vbvN+hNT0HZ6cVjpSDqKGVg/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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