SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8aee6b025a9706a618d7255fec12109252dd13e8dc015229a6db76512c337a8d' 
  AND token = '1qoYC0i1jjBlu6cFrxX+5QVjo4qa1aXiZJIBh7pHalg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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