SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3f2e363d07b150c663bbd2023d3ba5a77c48c8b8be302814571187bdcbb58c64' 
  AND token = '4UBVKlM7A5SZ5MgzdDavEq3YR13pZYwv2b0mtG9W8oc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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