bFigure 2.Berg’s original reconstructionsof a paleoniscid,Ganolepisgracilis(first published by Obruchev1955):a-Lateralviewofthe
entire fish, b -reconstruction of skull (ang =angular,aop=anteoperculum, cl =cleithrum, clv =clavicle, d =dentary, d sph =dermosphe-
notic, fr=frontal, i.o.c.=infraorbital sensory canal, i orb=infraorbital, max=maxillary, m c=Meckel’s cartilage, na=nasal, op=
operculum, pa =parietal, pcl -postcleithrum, p mx =premacilla, p oc=preopercular canal, p op =preoperculum, p r =postrostrale, pt =
posttemporal, r br =branchiostegal rays, scl =supracleithrum, sklr =sclerotic ring, so=suborbitalis,soc=supraorbital canal, sop=
suboperculum, st-it=supratemporal-intertemporal, tab =tabular).
tinopterygii.There is nocontemporarydata sup-
porting the hypothesis on thecloserelationship of
acipenseriforms toselachians’(Berg1948a, p. 53).
H e identifiedthreefamilies within Acipenseri-
formes:‘Chondrosteidae (fromthe LowerLias to
the LowerCretaceous), Acipenseridae(beginning
from theUpperCretaceous), andPolyodontidae
(beginningfrom theUpper Cretaceous)’(Berg
1948a, p. 54).Berg’sunderstanding ofAcipenseri-
formes asactinopterygians isfundamental to all
contemporary views (Sokolov & Berdichevskii
1989a,b,Grande &Bemis1991,Bemis et al.1997,
this volume).
Systematics ofAcipenseridae was thetopicof
one of Berg’s earlytheoretical papers(Berg1904).
H e includedfour genera inthis family:Husowith
two species,H. husoandH. dauricus; Acipenser
withsixteenspecies;Scaphirhynchuswith one spe-
cies,S. platorhynchus; andPseudoscaphirhynchus
withthreespecies,P. fedtschenkoi,P. hermanni, and
P.kaufmanni.Thisdivision ofAcipenseridaeinto
four genera isused by mostcontemporary research-
ers (but seeJollie 1980). In his firstmonograph on
the fishes ofRussia(Berg1911),BergdividedAci-
penserintothreesubgenera: (1)LioniscusBona-
parte,1846, with onespecies,A. nudiventris; (2)He-
lopsBonaparte,1846, also with one species,A. stel-
latus; and (3)Acipensersensustricto,which in-
cludes allotherspecies ofAcipenser.Later, in1948,
in the lastedition of his monograph on theRussian