SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43324a185449688056e9bb17d72d298c28ac4bae7418570952c3d096861b7cef' 
  AND token = '5+r4vjlaj+g9QuJT/GMNNs0fxpKc6ziqISuinWoZP20=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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