
NICHE, MORPHOLOGY AND LOCOMOTION IN LACERTID LIZARDS 
independent shifts to increased climbing in vegetation and this is 
associated with greater tail length. 
Apart from locomotory considerations, tail length in lacertids 
may be influenced by different patterns of predation associated with 
particular kinds of habitat. It has been suggested that long tails are 
more likely to be effective in deflecting the attack of ambushing 
predators and so would be expected in lizards that often hunt actively 
in complex spatial habitats where such predators might hide; in 
contrast it is predicted that more passively hunting lizards in open 
situations would have short tails. Some indications of such an 
association has been suggested for Southern African desert lacertids 
(Huey & Pianka, 1981) and, taking the family as a whole, nearly all 
species with very short tails are ground-dwellers in open situations. 
The only exception is the aberrant tree-dwelling and gliding Holaspis. 
The pattern of tail growth varies in lacertids. Relative tail length 
often increases with body size, for instance in L. dugesii, L. vivipara 
and L. jayakari, but decreases in Acanthodactylus scutellatus. In 
Lacerta lepida relative tail length rises steeply at first but sub- 
sequently levels out and eventually tends to fall and a similar growth 
pattern appears to be present in L. trilineata 
Limb proportions and structural niche 
Limbs of lacertids are often measured individually (see for instance 
Darevskii, 1967), but in intact animals it is difficult to determine a 
reliable reference point for the base of the limb which is situated in 
soft tissue. Because of this it is easiest to measure the total span of a 
pair of limbs when fully outstretched, from the tip of the longest digit 
on one side to that on the other. Fore and hind limb spans can then be 
compared with each other and with the total length of the head and 
body measured from the tip of the snout to the vent. The latter is of 
course not an absolute criterion for comparison. As already noted, 
presacral vertebral number varies between species and sexes, and 
this is also true of the size of the head relative to the body; both these 
factors affect body length. 
Estimates of hind leg span in terms of head and body length, and 
the ratio of foreleg and hind leg spans, are given for a wide variety of 
lacertids in Table | and the relative distribution of selected species in 
terms of these parameters is shown in Fig. 3. In the latter, the species 
all fall in a restricted area of the diagram. Not only do no forms exist 
where the forelimbs are longer than the hindlimbs but there is a 
broad correlation between hindlimb length and the relative length of 
the forelimbs: in cases where hindlimbs are comparatively short, 
forelimbs tend to approach them in length, but where hindlimb span 
is large, forelimb span is relatively much smaller. It follows from this 
that the overall range of hindlimb span in terms of body length is 
much greater than that of the forelimbs: for the former, the highest 
ratio is about 2.8 times the lowest compared with less than 1.5 times 
for the latter. 
The kind of structural habitats species occupy correlates quite 
clearly with limb proportions. Ground dwelling forms that often 
occur in dense vegetation or litter have short, subequal limbs and this 
_ is true of Lacerta andreanszkyi which appears to often spend time in 
the confining interstices of scree. Climbing forms are similar in 
proportion of the limb pairs although their legs are usually rather 
longer and this pattern is found both in climbers on open surfaces 
such as Holaspis and in forms from vegetation matrixes such as 
Gastropholis and Takydromus. Limbs are longer still in climbing 
forms that also utilise less steep surfaces quite extensively, such as 
Lacerta oxycephala. Forms which climb considerably but also run in 
more or less horizontal situations have even longer and less equal 
limb pairs. Species that scarcely climb and occupy open ground 
habitats all have very long hind legs and short front ones. This is best 
71 
Table 1 Limb proportions of lacertid lizards. HL/SV — Hindlimb span/ 
snout—vent distance; FL/HL — Forelimb span/hindlimb span; m — male, f 

— female. 
Species and sample size HL/SV FL/HL 
Male Female Male Female 
Takydromus amurensis (6m,4f) 1.02 1.03 78 Wy 
Takydromus septentrionalis (11m,10f) 1.08 1.02 78 Tl 
Gallotia atlantica (3m,3f) V2 ils .69 10 
Gallotia g. caesaris (3m,3f) 1.34 1.26 .69 .69 
Psammodromus algirus (6m,6f) 1.30 1.24 .65 64 
Psammodromus hispanicus (7m, 10f) 1.30 1.23 .68 10 
Lacerta vivipara (10m,10f) 0.99 0.81 82 78 
Lacerta agilis bosnica (10m,10f) 1.01 0.88 .80 .80 
Lacerta viridis (10m, 10f) 1.09 1.03 10 .69 
Lacerta trilineata (9m,10f) 1.20 1.20 64+ .64 
Lacerta lepida (5m,6f) 1.14 1.04 71 ol?) 
Lacerta pater (7m,5f) 1.11 1.10 74 Jf 
Lacerta andreanszkyi (1m,4f) 0.96 0.78 13) .86 
Lacerta laevis (10m,10f) 1.26 NEWT .66 .67 
Lacerta danfordi (7m,5f) 1.27 1.16 .67 .68 
Lacerta bedriagae (8m, 13f) 1.23 1.16 Al 10 
Lacerta mosorensis 10m,10f) 1.17 1.1 a7 74 
Lacerta oxycephala (10m,10f) 1.17 Hite) 74 We) 
Algyroides nigropunctatus (10m,7f) 1.25 Hey 71 14 
Lacerta perspicillata (9m,11f) 1.13 1.00 me 714 
Podarcis hispanica (9m,6f) 1.18 1.05 .69 al 
Podarcis m. fiumana (10m, 10f) 1.14 0.99 65 .67 
Podarcis muralis (10m, 10f) 1.12 1.03 71 sl 
Podarcis s. campestris 10m, 10f) 1.20 eZ .66 65 
Podarcis peloponnesiaca (19m,11f) 1.20 1.09 63 64 
Lacerta jayakari (7m,9f) 1.20 1.18 AS) fl?) 
Adolfus alleni (9m,7f) 0.94 0.87 alll 78 
Holaspis guentheri (3m,4f) 1.01 1.01 85 .80 
Gastropholis echinata (4m) 1.05 SL) 
Gastropholis tropidopholis (1f) 1.16 74 
Gastropholis vittata (1m,1f) 1.01 0.94 76 78 
Gastropholis prasina (1m) 1.04 HT 
Tropidosaura montana (3m) 0.88 8 
Tropidosaura gularis (1m,1f) Weil) 0.97 52 Hil 
Tropidosaura essexi (2m) 1.05 71 
Tropidosaura cottrelli (1m) 1.06 aT, 
Poromera fordi (3m,3f) eh) 1.28 aS) 74 
Nucras boulengeri (7m,7f) 1.03 1.01 wie. 71 
Nucras lalandei (4m,1f) 0.82 0.67 , Al) 
Philochortus intermedius (S5m,4f) 1.34 1.16 .60 .66 
Latastia longicaudata (10m,6f) 1.29 1.18 61 .63 
Heliobolus lugubris (7m,4f) 1.58 Neo 13} 8) 
Ichnotropis capensis (9m,5f) 1.38 1.29 64 .65 
Pseuderemias mucronata (12m,6f) 1.81 1.68 il 5) 
Meroles reticulatus (1m,4f) 1.73 1.58 .60 il 
Meroles ctenodactylus (3m,1f) Ned Ey .60 58 
Meroles cuneirostris (1f) 1.61 Si 
Meroles anchietae (2m,1f) 1.74 1.66 .62 .62 
Pedioplanis lineoocellata (4m,4f) 1.49 1.46 64 64 
Eremias persica (3m,5f) 1.38 IES .68 .69 
Acanthodactylus schmidti (12m,10f) 1.37 1.38 58 58 
Acanthodactylus scutellatus (10m,3f) 1.42 1.41 58 oy) 
Mesalina balfouri (6m,4f) 1.34 1.22 63 .64 
Mesalina ‘A’, SW Arabia (2m,4f) 1.20 1.04 69 2 
Mesalina ercolini (1f) 0.96 AY 
Ophisops e. schlueteri (5m,6f) 1.51 3 .62 61 
developed in Latastia and its sister group in the Armatured clade and 
reaches its extreme in forms like Heliobolus lugubris, Pseuderemias 
mucronata and the most derived species of Meroles. Among the 
species investigated here, advanced armatured ground dwellers are 
approached most closely in limb proportion within the primitive 
Palaearctic assemblage by Psammodromus, the species of Podarcis 
that climb least, and by Lacerta trilineata. 
Because of their correlation with spatial niche, limb proportions 
