SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f466ca0a043611594fd181d91ed108dcf84dc35d09d81e9c056dad57e6d373f' 
  AND token = '0P7hIPtxky5pjKdRv1NlpekG3SKgzZ/DaFUStmr2WVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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