Review of the fossil history of Old World vipers was

I

NTRODUCTION

In this paper we summarize the current knowledge

of the fossil history of true vipers (Viperinae). A

review of the fossil history of Old World vipers was

provided by Szyndlar and Rage (1999), but that study

was restricted almost exclusively to the oldest

remains, particularly those from lower and middle

Miocene deposits. In this study we include all fossil

remains of true vipers and their localities, from their

first appearance in the lowermost Miocene (ca. 23.8

Ma) until the latest Pliocene (ca. 2 / 1.64 Ma). The

latest Pliocene is sometimes considered the lowermost

Pleistocene because several decades ago the limit

between the Pliocene and Pleistocene was placed

about 2 / 1.8 Ma, whereas today this boundary is fixed

at 1.64 Ma (Harland et al., 1990). Basic data on par-

ticular Neogene fossils and their localities are listed in

Appendix I and II, and localities are mapped on

Figures 1 and 2. We have gathered published and

unpublished information on 171 fossil sites, of which

110 are Miocene and Pliocene localities. Hence, this

work reviews the fossil record of nearly all Old World

Viperidae, considering that with few exceptions (e.g.

Hasegawa et al., 1973; Hasegawa, 1980; Ivanov,

1999) fossil pitvipers have not been reported from the

Eastern Hemisphere.

Fifteen fossil species of the Viperinae (or presumed

Viperinae) have been described. Unfortunately, the

taxonomic status of most species and their phyloge-

netic relationships to extant vipers is unstable. The last

published list of extinct Viperidae was compiled by

Rage (in Golay et al., 1993), and herein we present an

updated version (see Appendix III).

The present work includes mostly members of

Vipera (sensu lato),  because the majority of fossil finds

of Old World Viperidae have been referred to this

genus. We employ the division of the genus Vipera

(sensu lato ) into four groups, based on osteological

traits that have commonly been used in paleontological

literature over the past two decades: (1) the Vipera

berus complex (comprised of, among others, the

extant species berus,  seoanei, and ursinii); (2) the

Vipera aspis complex (ammodytes,  aspis, and

latastei); (3) Vipera “Oriental vipers” (deserti, lebetina,

mauritanica,  palaestinae,  schweizeri,  xanthina); and

(4) Daboia (with a single living species, russelii ). The

reasons for using this arrangement (following, in part,

a concept introduced by Groombridge, 1980, and Obst,

1983) are explained below (Szyndlar and Rage, 1999).

OSTEOLOGY OF VIPERS: IMPLICATIONS FOR

PALEONTOLOGY

Recent systematic studies of Old World vipers

based on molecular data  are in disagreement with the

morphological findings of paleontologists, and it

appears necessary to briefly state our views regarding

problems arising from these molecular studies. The

systematics and taxonomy of extant members of the

Viperinae have recently undergone important changes.

Within the genus Vipera (sensu lato), several complexes

have been established and subsequently, entirely or in

part, removed from that genus and placed in another.

Opinions about relationships among particular mem-

bers of the group have also been controversial.

During the past decade, most proposed systematic

changes of the Viperinae have been based on bio-

chemical rather than morphological analyses.

Herrmann et al. (1992), for example, used immuno-

logical albumin comparisons and found the taxa

russelii and  lebetina (including former subspecies of

the latter) phylogenetically distinct, and revalidated

the generic names Daboia and  Macrovipera, respec-

tively. The  remaining related species (xanthina,

among others) were retained in the genus Vipera.

Recent studies (partly by the same authors), however,

FOSSIL RECORD OF THE TRUE VIPERS

Z

BIGNIEW

S

ZYNDLAR

1

AND

J

EAN

-C

LAUDE

R

AGE

2

A

BSTRACT

: The known fossil record of the Viperinae (true vipers) ranges in age from the earliest Miocene (ca. 23.8–22.8 Ma)

until Recent, and specimens originate from Europe, Africa, and Asia. At least 171 localities have yielded fossils of viperines, and

the majority have come from Europe and belong to the modern genus Vipera (sensu lato). Specimens from Africa and Asia are

restricted to several localities, and those from Africa are of the genera Bitis, Causus, Cerastes, Vipera, and perhaps Daboia. The

taxonomic allocation of Asiatic fossils, however, is unstable. With few exceptions, fossils of Crotalinae (pitvipers) have not been

reported from the Old  World. The oldest true vipers, known from isolated vertebrae and fangs, do not differ significantly from

their extant relatives. Although paleontologists at this time cannot provide much useful information on the origin and earliest

history of viperines, these events must have taken place prior to the Miocene and outside of Europe.

1

Polish Academy of Sciences, Institute of Systematics and Evolution

of Animals, Slawkowska 17, 31-016 Krakow, Poland

E-mail: [e-mail]  

2

Museum National d’Histoire Naturelle, UMR CNRS 8569,

Laboratoire de Paléontologie, 8, rue Buffon, 75005 Paris, France 

based on mitochondrial DNA (Joger et al., 1999; Lenk

et al., 2001), revealed that the taxa palaestinae and

mauritanica

(the latter previously considered a

member of  Macrovipera) should be placed in the

genus Daboia, whereas xanthina was considered to be

a member of the genus Macrovipera.

It is not our present aim to comment extensively on

interpretations and conclusions presented in the afore-

mentioned studies, as well as other papers, but we

contend that the radical changes in taxonomy (and

hence nomenclature) proposed in those studies based

on discoveries restricted to  a single (or several)

characters are not advisable. Although mtDNA evi-

dence, for example, apparently supported including V.

mauritanica and V. palaestinae in the genus  Daboia,

and  V. xanthina in  Macrovipera (Joger et al., 1999;

Lenk et al., 2001), earlier results generated from blood

serum albumin characters produced different results

(Herrmann et al., 1992). Our concern with molecular

studies is in the methods of determining which mole-

cules are better suited for sorting taxa and recon-

structing phylogenies. Are blood serum albumins less

important than mitochondrial DNA? To us, it would

appear that such choices regarding selection of mole-

cular markers are more subjective than realized.

In paleontology, estimates of the taxonomic status

of a given fossil and its relationship with extinct or

extant species rely on comparisons of skeletons with

those of extant relatives. Phylogenetic relationships

hypothesized from skeletal characters are not always

concordant with those based on molecular characters.

On the basis of osteology, most members of extant

Oriental vipers (deserti,  lebetina,  mauritanica,

palaestinae,  schweizeri,  xanthina) closely resemble

each another, a situation that also occurs within the V.

berus and V. aspis complexes. For example, when we

work with fossil remains of European Oriental vipers,

it is normal practice to first compare all remains with

skeletons of lebetina and xanthina, species that today

inhabit areas in Asia Minor located near ancient

migratory routes. With rare exceptions, ophidian fossil

remains are fragmentary and usually consist of isolated

vertebrae. Considering the close osteological similar-

ities of these recent species, in most cases it is clear

that fossil remains cannot answer the crucial question

of which lineage is represented. For this reason, we

420

Z. Szyndlar and J. Rage

Fig. 1. Neogene localities of the Viperinae in the West Palaearctic. See abbreviations in Appendix I.

feel that the use of the generic name Macrovipera

(recently used in paleontological papers) is baseless,

although one of us (JCR) was obliged to use this

genus for practical reasons in Golay et al. (1993).  

The osteology of recent Viperinae is poorly studied,

and the lack of comparative materials has made iden-

tification of fossil remains difficult or impossible.

There is great intraspecific variation in the skeletal

elements of the Viperinae, which remains largely

unknown due to the scarcity of viperine skeletons in

museum collections, and only a few authors have

discussed intraspecific variation in the skull bones

(Zerova and Chikin, 1992; Chikin, 1997).

Another example of the aforementioned problems

is the taxonomic status of V.  burgenlandica of the

Austrian Miocene. In the description of this extinct

species, Bachmayer and Szyndlar (1987) considered it

to be a close relative of the extant V. xanthina, based

mostly on the similarity of the basiparasphenoid.

Discovery of another basiparasphenoid, apparently

belonging to V. burgenlandica but resembling that of

V. lebetina, and not that of  V. xanthina, suggests a broad

spectrum of intraspecific variation in V. burgenlandica

(Szyndlar, 1991). Paradoxically, while our knowledge

of fossil species has increased, their relationships with

extant species become enigmatic.

A more interesting example of intraspecific varia-

tion that occurs in fossil snakes is found in V. gedulyi

from the Hungarian Miocene, described by Bolkay in

1913. Although the description was based on a large

number of cranial elements, only four bones (a maxilla,

a fragmentary ectopterygoid, a basioccipital, and a

basiparasphenoid) were illustrated (Bolkay, 1913,

Plate 12: Figs. 9–12). This material was subsequently

examined by von Szunyoghy (1932), but remained

inaccessible until 1991 when one of us (ZS) was

allowed to examine Bolkay’ s collection (see Szyndlar,

1991: notes added in the proof). For a detailed

description of the snake and numerous illustrations,

see Venczel , 1994. Figure 3 shows four of 16 syntype

basiparasphenoids of V.  gedulyi, whereas Figure 4

presents nine of 16 syntype maxillae of the same

snake. Differences among the bones are striking, and

if it was the case that these particular bones originated

from different paleontological localities, they could

have been described as distinct species! This is easily

Biology of the Vipers

421

Fig. 2. Neogene localities of the Viperinae in the Old World, exclusive of the West Palaearctic. See abbreviations in Appendix I.

understood considering that ophidian paleontologists,

unfortunately, usually have few (if any) comparative

skeletons of related Recent snakes to examine.

Osteologically, disregarding variation at the

species level, the subfamily Viperinae, and Vipera

(sensu lato) in particular, form a highly homogeneous

group with certain members displaying similar mor-

phology in both skulls and vertebrae, unlike in other

snakes. For example, in the Colubridae, it is usually

difficult to properly identify isolated fossil vertebrae,

but in most cases identification of cranial bones of

European colubrids is not troublesome (von

Szunyoghy, 1932; Rabeder, 1977). Despite these

problems, the osteology of the Viperinae generally

permits identification. More importantly, this allows

us to recognize assemblages that are morphologically

homogeneous. On this account, we stress that most

osteological characters within Vipera  (sensu lato) do

not support the systematic changes proposed on the

basis of molecular data.

Vertebral features of different groups of Vipera

(sensu lato) were discussed by Szyndlar and Rage

(1999). In summary, particular complexes of Vipera

are characterized by differences in vertebral mor-

phology, but it is extremely difficult  (if not impossible)

to differentiate vertebrae belonging to members of the

same complex. Similarly, the cranial morphology of

most extant members of  Vipera (sensu lato) is highly

422

Z. Szyndlar and J. Rage

Fig. 3. Vipera gedulyi Bolkay, 1913 from the Miocene of Polgárdi. Four basiparasphenoids, in ventral and left lateral views (syntypes,

part.; Museum of the Hungarian Geological Institute, Budapest, Ob-4467/Vt.74). Abbreviations: afVc, anterior foramen of Vidian canal;

cf, cerebral foramen; pfVc, posterior foramen of Vidian canal. Note the intraspecific variation in the general shape of  the bone as well as

in the disposition of the foramina.

homogeneous, and morphological differences can be

only observed between particular complexes rather

than within them. The only exception is russelii. Its

osteology fully supports placement in the genus

Daboia, as suggested by Szyndlar (1988), and as

indicated by molecular characters (for information

on the distinctiveness of the vertebrae of russelii,

see Szyndlar and Rage, 1999). In cranial osteology,

significant differences are evident between russelii

and other members of the genus Vipera (sensu lato),

such as extremely elongated skull bones in russelii

(an apomorphic character) (Fig. 5).

In summary, osteological characters support a

division of the genus Vipera (sensu lato) into three

separate complexes. In the following section we con-

sider most extinct European viperines as members of

the genus Vipera. Exceptions are D. maxima from the

Spanish Pliocene, thought to be a close relative of the

living D. russelii , and several fossil species that we

consider nomina dubia or nomina nuda.

THE OLDEST TRUE VIPERS

The oldest Viperidae have been reported from a

few lowermost Miocene (MN 1) sites in western

Europe. They are Provipera boettgeri from Hessler,

Germany (Kinkelin, 1892), V. antiqua from Weisenau,

Germany (Szyndlar and Böhme, 1993), and perhaps a

Vipera from St-Gérand-le-Puy complex, France

(Hoffstetter, 1955). The systematic status of P.

boettgeri, based on isolated venomous fangs, is uncer-

tain and was considered a nomen dubium by Rage

(1984). Although it is impossible to determine

whether isolated fangs represent a true viper or

pitviper, they no doubt belonged to a member of the

family Viperidae. The remains from the two latter

aforementioned localities represent snakes of the V.

aspis complex (Szyndlar and Rage, 1999).

The oldest European vipers are also the oldest

representatives of the family Viperidae. The oldest

viperine fossil in the New World, slightly younger than

European fossils, is a vertebral fragment resembling

Biology of the Vipers

423

Fig. 4. Vipera gedulyi Bolkay, 1913 from the Miocene of Polgárdi. Nine maxillae (6 right and 3 left), in antero-ventral views (syntypes,

part.; Museum of the Hungarian Geological Institute, Budapest,  Ob-4467/Vt.74). Abbreviations: ap, ascending process; fdc, foramen of

dental canal. Note the intraspecific variation in the shape of the ascending process as well as in the presence vs absence of the foramen

piercing the process.

424

Z. Szyndlar and J. Rage

Fig. 5. Dorsal view of the braincase of three extant vipers: (A) Vipera berus; (B) Vipera lebetina; (C) Daboia russelii . All specimens from

the Institute of Systematics and Evolution of Animals, Polish Academy of Sciences (catalogue numbers 415, 481, and 362, respectively)

Fig. 6. Neogene and recent occurrence of Vipera (aspis complex) in the West Palaearctic. The range of recent distribution (shaded area)

after Gasc et al. (1997) (Europe), Joger (1997) (West Asia), Bons and Geniez (1996), and Schleich et al. (1996) (North Africa).

the pitviper Sistrurus from the lower Miocene (latest

Arikareean) of Nebraska (Holman, 1981). Apart from

three badly preserved remains, which are impossible

to identify at the subfamily level, all other viperid fos-

sils from North America have been referred to as

pitvipers (Holman, 2000).

As with other snakes, fossil remains of the

Viperidae are mostly isolated vertebrae. The oldest

fossils of the Viperidae in Europe are vertebrae (local-

ities of Weisenau and the St-Gérand-le-Puy complex)

and fangs (Hessler and St-Gérand-le-Puy). Hoffstetter

(1962) reported the presence of “un maxillaire et des

crochets comparables à ceux des Vipères modernes”

from the French Aquitanian (probably Saint-Gérand-

le-Puy and/or other localities), but unfortunately the

maxilla has not been found. The oldest maxillae

available are those of V. maghrebiana from the middle

Miocene (MN 7-8) of Beni Mellal in Morocco (Rage,

1976) and Vipera from the coeval La Grive in France.

The latter locality has also yielded a number of basi-

parasphenoids from members of the Oriental vipers and

the V. aspis complex. The cranial bones from La Grive

remain undescribed (see Szyndlar and Rage, 1999).

Cranial elements of the Viperidae are more fragile

than homologous elements from most other snakes,

and thus skull remains are rarely found. The most

notable exception is the fossil remains of V.  gedulyi

from the Hungarian latest Miocene (MN 13), which

consist of abundant and diverse cranial elements

(Bolkay, 1913; Venczel, 1994; see Figs. 3–4). Skeletal

elements of the Viperidae, including the oldest forms,

do not differ substantially from the bones of recently

living species. For example, the vertebrae of the oldest

viper,  Vipera cf.  V.  antiqua from the lowermost

Miocene of Weisenau, are strikingly similar to those

of the living V.  ammodytes (Szyndlar and Böhme,

1993; Fig. 6). Therefore, although there is no direct

supportive evidence, the genus Vipera must have

evolved before the Miocene, and apparently outside of

Europe. Important events in the history of the

Viperinae are presented in Table 1.

HISTORY OF VIPERS IN EUROPE

Lower and Middle Miocene

Appearance of the “aspis-like” vipers was one of

the most important novelties in the composition of the

European snake fauna at the beginning of the Miocene

(MN 1). From that point on, remains of the genus

Vipera are abundant in European fossil sites.  

At the lower / middle Miocene transition (i.e., around

the biozone MN 4), dramatic changes occurred in the

composition of the European ophidian fauna. This

phenomenon is correlated with the thermal maximum

observed in European climate, and results from

competition of autochthonous species with new waves

of invaders from the East, composed principally of

modern colubrids, elapids, and large members of the

genus  Vipera (i.e., Oriental vipers). Following the

arrival of new snakes at the end of the lower

Miocene, “archaic” components of the European

snake fauna (mainly boas) became rare in fossil

materials and disappeared before the end of the middle

Miocene. Interestingly, an overwhelming majority of

“modern” elements of the European snake fauna that

inhabited Europe from the middle Miocene onward

were closely related to recent species, although not

necessarily in the European continent (Demarcq et

al., 1983; Szyndlar and Böhme, 1993; Szyndlar and

Schleich, 1993). Members of the genus Vipera, both

Oriental vipers and aspis-like snakes, were important

components of the modern ophidian fauna of the

European Miocene. 

Late Miocene and Pliocene

In the long period between the lower / middle

Miocene transition and the end of the Pliocene,

Oriental vipers and members of the V. aspis complex

occurred sympatrically as part of the common

European snake faunas, as indicated by the abundant

fossil record from many localities, especially from

areas close to the Mediterranean basin.

Most extinct species of the Viperidae described

from Europe are Oriental vipers of Miocene age.

Unfortunately, due to the scarcity of fossils and the

osteological similarity of many vipers, it is not sur-

prising that most extinct species are hardly distin-

guishable from one another and from extant relatives

(Szyndlar and Rage, 1999). An important event in the

middle Pliocene in Spain was the appearance of a

giant viper (V. maxima) with vertebrae that resemble

those of the living genus Daboia from southern Asia.

The relationship between V. maxima and D. russelii is

evident in their posterior trunk vertebrae; both have

high neural spines and short hypapophyses, unlike the

Oriental vipers (Szyndlar, 1988). The presence of a

close relative of a viper in western Europe that today

inhabits tropical Asia may seem astonishing. There is,

however, evidence supporting a close affinity between

Iberian and north African faunas in the Neogene.

Moreover, there is evidence that many Neogene ani-

mals, including several snakes, may have inhabited

vast areas along the southern coast of the

Biology of the Vipers

425

Mediterranean Sea, from Iberia in the West to western

Asia in the East (Szyndlar, 1985, 1987b, in press, b).

Fossil material from western and central Europe

indicates that the smallest representatives of the genus

Vipera (i.e., the V. berus complex) were absent in the

area in the Miocene and Pliocene. The only known

exceptions are remains resembling V. ursinii from the

late Miocene (MN 12) of Tardosbánya in Hungary

(M. Venczel, unpublished), and a single vertebra

presumably of  V.  berus from the late Pliocene (MN

16) of Bad Deutsch Altenburg 20 (Szyndlar, 1991).

Besides these records, members of the V. berus com-

plex appeared in western and central Europe during

the transition between the latest Pliocene and lower-

most Pleistocene (MN 17).

In eastern Europe (the Ukraine), however, small

vipers with strongly reduced neural spines on their

trunk vertebrae (and thus referred to the V.  berus

complex) were  common from at least the end of the

Miocene. The taxonomic status of the oldest remains

found in the area (in Gritsev and other sites), originally

reported as “Vipera (Pelias) sp.” (Zerova, 1987, 1993)

is uncertain, because of the poor state of preservation

of available material (Szyndlar, 1991). The inability of

these snakes to colonize the rest of Europe in the late

Miocene and Pliocene may have resulted from the

presence of aspis-like snakes in areas east of the

Ukraine. The true vipers inhabiting the Ukraine in the

late Miocene were accompanied by pitvipers, as evi-

denced by crotaline maxillae (with characteristic fossa

in the pit organ) found in Gritsev (Ivanov, 1999). This

fossil is the only evidence that confirms the existence

of the Crotalinae in Europe.