SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed229127fbee645b3d44309e95030d0c1672ea49a5f765b5fd6dd5444a4a5377' 
  AND token = 'u5H8svAuYz57F9JXa3fgLIxbDgGWMaQdqtEIpjIvjUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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