SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f9da4a176a8dd49ba654561cd26a74fea6b4e2309b0ccf24bf87887c5dd99b86' 
  AND token = 'gEJd9bY/jF/FCmqCh5ibsUlnrUurlZ1WX4Vpa51BvmI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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