Table 2. Overview of data justifying the need for a novel mononegavirus family for NYMV, MIDWV, and SbCNV-1.

Mononegavirus family	Member inclusion criteria as defined by the ICTV [19, 32, 46, 47]	Contradictory properties of NYMV, MIDWV, and SbCNV-1 [3, 23, 42]
Bornaviridae
	Genomes ≈9 kb in length	Genomes ≈11 kb in length
	Overlapping genes	No overlapping genes
	Gene splicing	unlikely
	Single matrix protein	NYMV and MIDWV: two matrix proteins
	N-glycosylated matrix protein	NYMV, MIDWV, and SbCNV-1 matrix proteins not N-glycosylated
	Spherical virions ≈90 nm in diameter	NYMV and MIDWV particles spherical and ≈ 130 nm in diameter
	Infect mammals and birds, but not arthropods or nematodes	NYMV and MIDWV infect ticks; SbCNV-1 infects nematodes
Filoviridae
	Genomes ≈19 kb in length	Genomes ≈11 kb in length
	Overlapping genes	No overlapping genes
	RNA editing of the GP gene	no evidence of a slippery sequence in NYMV, MIDWV, or SbCNV-1 G genes
	3′ and 5′ genomic ends are fully complimentary	NYMV 3′ end protruding
	Replication exclusively in the cytoplasm	NYMV replication in the nucleus
	Formation of branched, 6-shaped, or filamentous virions ≥ 800 nm in length	NYMV and MIDWV particles spherical and ≈130 nm in diameter
	Infect nonhuman primates, pigs, and bats, but not arthropods or nematodes	NYMV and MIDWV infect ticks; SbCNV-1 infects nematodes
	Endemic in sub-Saharan Africa, Spain, and the Philippines	Not known to be endemic in these areas
	Cause viral hemorrhagic fever in humans and nonhuman primates	Not known to cause any disease in humans or nonhuman primates
Rhabdoviridae
	3′ and 5′ genomic ends are fully complimentary	NYMV 3′ end protruding
	Single matrix protein	NYMV and MIDWV: two matrix proteins
	Replication exclusively in the cytoplasm (all rhabdoviruses except nucleorhabdoviruses)	NYMV replication in the nucleus
	Bullet-shaped, cone-shaped or bacilliform virions	NYMV and MIDWV particles spherical
	Infect all kinds of animals, plants, and arthropods, but not nematodes	NYMV and MIDWV infect ticks; SbCNV-1 infects nematodes
Paramyxoviridae
	Genomes ≈15 kb in length	Genomes ≈11 kb in length
	3′ and 5′ genomic ends are fully complimentary	NYMV 3′ end protruding
	RNA editing of the P gene	no evidence of a slippery sequence in NYMV, MIDWV, or SbCNV-1 P genes
	Replication exclusively in the cytoplasm	NYMV replication in the nucleus
	Single matrix protein	NYMV and MIDWV: two matrix proteins
	At least two envelope proteins constituting the fusion machinery	One envelope protein
	Virions ≥150 nm	NYMV and MIDWV particles spherical and ≈ 130 nm in diameter
	Not known to infect ticks or nematodes	NYMV and MIDWV infect ticks; SbCNV-1 infects nematodes