SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e364c1cbfe9f1afccc9fafb245b72cd7a0265874c685f3304397641e36a5602' 
  AND token = 'PztlovlBHkPDPNvfu+YNXdPKtUl6JXY+mdaPtI41pWo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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