▁differ ▁from ▁any ▁nom ina ▁n uda ▁that ▁describe ▁the ▁same ▁spec imen . ▁N omen ▁ob lit um ▁( Lat in ▁for ▁" f org ot ten ▁name " ): ▁A ▁name ▁that ▁has ▁not ▁been ▁used ▁in ▁the ▁scientific ▁community ▁for ▁more ▁than ▁fifty ▁years ▁after ▁its ▁original ▁proposal . ▁Pre occup ied ▁name : ▁A ▁name ▁that ▁is ▁formally ▁published , ▁but ▁which ▁has ▁already ▁been ▁used ▁for ▁another ▁tax on . ▁This ▁second ▁use ▁is ▁invalid ▁( as ▁are ▁all ▁subsequent ▁uses ) ▁and ▁the ▁name ▁must ▁be ▁replaced . ▁As ▁pre occup ied ▁names ▁are ▁not ▁valid ▁generic ▁names , ▁they ▁will ▁also ▁go ▁un ital ic ized ▁on ▁this ▁list . ▁N omen ▁dub ium ▁( Lat in ▁for ▁" d ub ious ▁name " ): ▁A ▁name ▁describing ▁a ▁foss il ▁with ▁no ▁unique ▁di agnostic ▁features . ▁As ▁this ▁can ▁be ▁an ▁extremely ▁subject ive ▁and ▁controvers ial ▁design ation , ▁this ▁term ▁is ▁not ▁used ▁on ▁this ▁list . ▁ ▁The ▁list ▁ ▁See ▁also ▁▁ ▁List ▁of ▁pre histor ic ▁brit t le ▁stars ▁ ▁List ▁of ▁pre histor ic ▁sea ▁c uc um bers ▁ ▁List ▁of ▁cr ino id ▁gener a ▁ ▁References ▁▁▁ ▁Category : List s ▁of ▁pre histor ic ▁e chin od erm s ▁Ed rio aster oid s <0x0A> </s> ▁V ad im ▁Pet rov ▁( born ▁ 2 4 ▁May ▁ 1 9 3 2 ) ▁is ▁a ▁Czech ▁composer ▁of ▁Russian - C zech ▁descent