When we think of amber inclusions we usually think of insects and other small animals, but this is as shortsighted as thinking that "biology" refers only to animal life forms! Just as "biology" refers to botany as well as zoology, amber contains plant as well as animal fossils.

In the game of "20 questions", the first question is usually "Is it animal, vegetable or mineral?" In the case of amber, it is difficult to answer that question precisely because although it clearly has vegetable origins, it is primarily mineral, and can include fossils that are either animal, vegetable or both. Some delicate, usually ephemeral, mineral structures such as water droplets and air bubbles can also be found preserved in amber.

In this case the main inclusion is obviously botanical, although a microscopic examination might reveal tiny animals or pieces of larger ones. But what exactly is it? My guess is that it is the outer "husk" of some kind of plant. The species is almost certainly extinct now, just as trapped insects represent a species , but not necessarily genus or family, that is now extinct.