Filamentous, maybe enveloped. the ribonucleocapsid has a diameter of 20nm, and is 300-400 nm long.
Negative-stranded RNA linear genome, about 10 kb in size. Encodes for six proteins. Enzyme:RNA dependent RNA polymerase, RNA guanylyl transferase, mRNA methyltransferase.
The viral RNA dependent RNA polymerase binds the encapsidated genome at the leader region, then sequentially transcribes each genes by recognizing start and stop signals flanking viral genes.