SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fbf22c7bcb6d3a1e44f62cf6a691fafa7c6d72fed00dda96552f30f782af684' 
  AND token = 'clCSNuOGql/tHn7KTHAup0ZmAP2H/EXwL8m+6MVvSjw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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