A new black-bellied snake (Pseudoxyrhophiinae: Liophidium) from western Madagascar, with notes on the genus Pararhadinaea

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Amphibia-Reptilia 30 (2009): 173-183

 A new black-bellied snake (Pseudoxyrhophiinae: Liophidium) from
    western Madagascar, with notes on the genus Pararhadinaea

     Michael Franzen1 , Julia Jones2 , Achille P. Raselimanana3 , Zoltán T. Nagy4 , Neil D’Cruze5 ,
                                            Frank Glaw1 , Miguel Vences6, ∗

Abstract. We describe Liophidium maintikibo, a new species of pseudoxyrhophiine snake from the dry deciduous forest
of Kirindy, western Madagascar. The new species is related to Liophidium therezieni but differs by a lower number of
ventral scales and several details of colouration. Its ventral scales have a large central black patch which is missing from the
subcaudals. This predominantly black ventral side is similar to that of another enigmatic Malagasy snake, Pararhadinaea
melanogaster, for which we here present evidence for two new locality records, Ankarana and Daraina in northern
Madagascar. The phylogenetic relationships of P. melanogaster (the sole representative of a monotypic genus) have so far not
been clarified. Similarities to Liophidium maintikibo may indicate affinities to Liophidium, but P. melanogaster differs from
this new species by a lower number of ventrals, subcaudals, number of maxillary teeth and by a different dorsal colouration.

Keywords: Liophidium maintikibo sp. n., Liophidium therezieni, Madagascar, molecular relationships, new distribution
records, Pararhadinaea melanogaster, Squamata: Serpentes: Lamprophiidae.

Introduction                                                          Boettger, 1898, may also be related to Li-
                                                                      ophidium. This genus has been reviewed by
The genus Liophidium Boulenger, 1896, cur-
                                                                      Domergue (1984b) who also described a sub-
rently contains eight species of small terres-
                                                                      species of P. melanogaster, P. m. marojejyen-
trial snakes, including seven Malagasy taxa and
                                                                      sis and a new species that he assigned to
one endemic of Mayotte in the Comoro is-
                                                                      the genus as Pararhadinaea albignaci. Sub-
lands. Species of the genus are morphologi-
                                                                      sequently, Raxworthy and Nussbaum (1994)
cally rather similar. Liophidium has not been
                                                                      placed Pararhadinaea near Pseudoxyrhopus
subjected to a comprehensive revision since
                                                                      and Heteroliodon. This view was rejected by
the work of Domergue (1984a) who described
                                                                      Cadle (1999) who also stressed that Liophidium
three new species (L. apperti, L. therezieni,
                                                                      is only weakly defined among the Pseudoxyrho-
L. chabaudi).
                                                                      pus group and that monophyly within Lio-
   A recent molecular study (Glaw et al.,
2007) suggests a relationship between Lio-                            phidium is poorly corroborated (Cadle, 1999:
phidium and species of Liopholidophis Moc-                            435-436). Cadle (1999) transferred the sec-
quard, 1904. The monotypic Pararhadinaea                              ond species of Pararhadinaea as Exallodon-
                                                                      tophis albignaci to a newly described, mono-
                                                                      typic genus, leaving P. melanogaster (including
1 - Zoologische Staatssammlung München, Münchhausen-                  its subspecies marojejyensis) as the sole repre-
    str. 21, 81247 München, Germany
2 - School of the Environment and Natural Resources, Ban-             sentative of the genus.
    gor University, LL57 2UW, Wales                                      The present study contributes to the sys-
3 - Départment de Biologie Animale, Université d’Anta-                tematics of Liophidium by describing a new
    nanarivo, BP 906, Antananarivo, 101 Madagascar
4 - Royal Belgian Institute of Natural Sciences, rue Vautier          species from Kirindy forest in western Mada-
    29, B-1000 Brussels, Belgium                                      gascar which is clearly assigned to this genus
5 - The World Society for the Protection of Animals, 89 Al-           by molecular data. We compare the new species
    bert Embankment, London, SE1 7TP, United Kingdom
6 - Technical University of Braunschweig, Zoological Insti-
                                                                      to its presumed closest relative, Liophidium
    tute, Spielmannstr. 8, 38106 Braunschweig, Germany                therezieni, as well as to Pararhadinaea melano-
    ∗ Corresponding author; e-mail: m.vences@tu-bs.de                 gaster and provide data on newly collected

                            © Koninklijke Brill NV, Leiden, 2009. Also available online - www.brill.nl/amre
174                                                                                                         M. Franzen et al.

Table 1. Voucher specimens and GenBank accession numbers of the snakes included in the molecular analysis.

Species                            Sample       Locality information          Voucher specimen                    GenBank
                                     ID                                                                         accession no.

Dromicodryas bernieri                J91        Ifaty                         UADBA (FGMV 2000-517)              AY188014
Dromicodryas quadrilineatus          J66        Sambava                       not collected                      AY188015
Thamnosophis lateralis               J93        near Mantasoa                 UADBA (FGMV 2000-36)               DQ979977
Thamnosophis stumpffi               J331        Nosy Be                       ZSM 579/2001                       DQ979986
Exallodontophis albignaci          Z2220        Andasibe                      UADBA (ZCMV 2220)                  EU394724
Liopholidophis sexlineatus           J98        Mandraka                      UADBA (FGMV 2000-38)               AY188024
Liopholidophis dimorphus           F491         Montagne d’Ambre              ZSM 252/2004                       DQ979980
Pseudoxyrhopus ambreensis           J102        Montagne d’Ambre              not collected                      AY188035
Liophidium chabaudi                Tp844        not available                 not available                      EU394721
Liophidium torquatum                 J84        Montagne d’Ambre              not collected                      AY188023
Liophidium torquatum                J307        Ranomafana (Vohiparara)       ZSM 691/2003                       DQ979984
Liophidium vaillanti                B27         near Kirindy                  not collected                      EU394720
Liophidium vaillanti                B32         near Kirindy                  not collected                      DQ979995
Liophidium therezieni              M07-2        Montagne des Français         ZSM 2053/2007                      EU394722
Liophidium maintikibo              M07-3        near Kirindy                  ZSM 2052/2007                      EU394723
Liophidium rhodogaster              J304        Ranomafana NP                 ZSM 784/2003                       DQ979978
Liophidium rhodogaster             F466         Montagne d’Ambre              ZSM 238/2004                       EU394719
Liophidium rhodogaster             F467         Montagne d’Ambre              UADBA (FGZC 467)                   DQ979992

specimens of both these poorly known snake                           Phylogenetic reconstructions were carried out using
species.                                                         PAUP* 4b10 software (Swofford, 2002). We performed
                                                                 parsimony analyses with 2000, and maximum likelihood
                                                                 heuristic searches with 100 bootstrap replicates, respec-
                                                                 tively. In the data set including outgroups, 410 of the total
Materials and methods                                            1117 characters were parsimony-informative, and a single
                                                                 most parsimonious tree was found. For maximum likelihood
The snakes were generally anaesthetized by injection with        analysis, the nucleotide substitution model HKY + I + G
chlorobutanol, fixed in either formalin or 95% ethanol,          was selected using the Akaike information criterion (AIC).
and subsequently stored in 70% ethanol. Muscle tissue            Bayesian analyses of phylogenetic inference (BI) were car-
samples were taken either from freshly killed snakes or          ried out using MrBayes v3.1.2 (Ronquist and Huelsenbeck,
from ethanol-fixed specimens 1-2 years after collection          2003) running 2×106 generations under the HKY + I + G
and preserved in 98% ethanol. Measurements were taken            substitution model selected by the software MrModeltest
to the nearest millimeter with a caliper or a ruler. We          (Nylander, 2004). In BI, the first 25% of the trees (5000
follow Cadle (1996) regarding the terminology of meris-          trees) were discarded, and the remaining 15 000 trees were
tic and mensural data. Ventral scales were counted with-         evaluated.
out preventrals. Institutional abbreviations are: Museum             New sequences determined in this study were deposited
National d’Histoire Naturelle, Paris (MNHN); Naturhis-           in GenBank under the accession numbers EU394719-
torisches Museum, Wien (NMW); Forschungsinstitut und             EU394724. Data on voucher specimens and Genbank ac-
Naturmuseum Senckenberg, Frankfurt am Main (SMF);                cession numbers are given in table 1. Material used for mor-
Université d’Antananarivo, Département de Biologie An-           phological comparisons is listed in the appendix. Pararhad-
imale (UADBA); Zoologische Staatssammlung München                inaea was omitted from genetic analyses since we had no
(ZSM).                                                           tissue samples available.
    A standard method was used for total genomic DNA
extraction (Sambrook, Fritsch and Maniatis, 1989). The
complete cytochrome b gene was amplified with primers
L14910, L14919 and H16064 (Burbrink, Lawson and
                                                                 Results
Slowinski, 2000; modified by de Queiroz, Lawson and
Lemos-Espinal, 2002), and directly sequenced with L14903
                                                                 Liophidium maintikibo sp. n. (figs 1-3)
(a 5 end of L14910), L-410 and H-391 (Nagy et al., 2003).
                                                                 Pararhadinaea/Liophidium sp.“Kirindy”– Glaw
    All sequences were checked for their quality by eye, and
for their mitochondrial origin (i.e., they were translated to    and Vences (2007): 430-431.
amino acids and checked for stop codons as well as for
higher substitution rates in third positions which is typical    Holotype. ZSM 2052/2007, collected near Ki-
for coding sequences). Sequences were aligned manually.          rindy research station (20◦ 03 S, 44◦ 39 E), el-
A new black-bellied snake (Pseudoxyrhophiinae: Liophidium)                                                            175

Figure 1. Liophidium maintikibo sp. n. (holotype, ZSM 2052/2007), drawing of head in (a) dorsal and (b) lateral view. Scale
bar represents 1 mm.

Figure 2. Holotype of Liophidium maintikibo (ZSM
2052/2007) in life.

evation below 100 m, about 60 km north of
Morondava (district of Morondava, region of
Menabe, Toliara Province), western Madagas-                     Figure 3. Holotype of Liophidium maintikibo (ZSM
car, by Julia Jones on 20 November 2004.                        2052/2007) in life, ventral side.
176                                                                                                        M. Franzen et al.

Diagnosis. Liophidium maintikibo sp. n. dif-                    per and lower dark margins of lateral band nar-
fers from the only Comoran species L. may-                      row (vs. equivalent lines broad), dorsolateral
ottensis by 17 rows of dorsal scales (vs. 19)                   stripe absent or weak (vs. dorsolateral stripe
and from the Malagasy species (which all share                  broad), gular region heavily mottled with dark
17 rows of dorsal scales) as follows: from L. ap-               brown markings (vs. gular region with sparse
perti, L. chabaudi, L. rhodogaster, L. torquatum                dark markings), light ventral colouration bright
and L. trilineatum by the lack of a loreal scale                yellow in life (vs. light ventral colouration pink-
and the presence of only seven upper labials,                   ish white in life), ventral scales with a median
with upper labials 3 + 4 touching the eye (vs. 8                oval blotch, forming one broad mid-ventral line
upper labials, 4+5 touching the eye). Moreover,                 (vs. ventral scales mostly with two lateral mark-
it differs from the above mentioned species (ex-                ings, forming two indistinct lateral rows), sub-
cept L. rhodogaster) by a higher number of ven-                 caudals immaculate (vs. subcaudals with lateral
tral scales and by a different dorsal colouration               markings).
(5 dorsal stripes vs. 0, 1 or 3 stripes; except                    The new species differs from the two taxa
L. apperti).                                                    of the morphologically similar genus Pararhad-
   From the remaining Liophidium with seven                     inaea (P. melanogaster melanogaster, P. m.
upper labials and no loreal scale L. maintikibo                 marojejyensis) by a higher number of ventral
sp. n. differs from L. vaillanti by fewer ventral               scales (193 vs. 147-180), a higher number of
scales (193 vs. 220-255) and colouration (e.g.,                 subcaudals (56 vs. 41-45), a high number of
presence of a light nuchal band, lack of a broad                maxillary teeth (23 vs. 13-14) and by a differ-
and well defined light lateral band, presence of                ent colouration (presence of a light nuchal band
a broad longitudinal mid-ventral stripe of oval                 and no well defined strongly contrasting light
blotches). It also differs from L. vaillanti by                 and dark stripes).
a smaller total length (255 mm vs. max. 858                     Description of holotype. Probably adult, sex
mm, see comments on earlier available names                     unknown, in good state of preservation. Snout-
below).                                                         vent length 205 mm, tail length 50 mm (to-
   The new species resembles its apparent sister                tal length 255 mm; tail length 19.6% of total
taxon Liophidium therezieni in most characters.                 length). Head length 7.4 mm, head width 3.8
It differs from the latter by having fewer ven-                 mm; eye large, 1.1 mm in diameter, pupil round.
tral scales (193 vs. 218-235, table 2) and in sev-                 Ventral scales 193, three preventrals; cloacal
eral aspects of the dorsal and ventral coloura-                 plate divided; subcaudal pairs 56. Dorsal scales
tion: upper labials predominantly dark, mostly                  smooth, no apical pits; in 17-17-15 longitudinal
with a small light marking each (vs. upper labi-                rows; scale row reduction from 17 to 15 at level
als light, with sparse dark markings), broad dark               of ventral 119. Rostral scale broad, reaching
lateral band (vs. no distinct lateral band), up-                onto the dorsal side of head. Internasals and pre-
Table 2. Mensural and meristic data of Liophidium therezieni. ToL – total length; SVL – snout-vent length; TL – tail length;
V – ventrals; SC – subcaudals; HL – head length; HW – head width; ED – eye diameter; HT – holotype; PT – paratype (data
from Domergue, 1984).

                         Locality                  Sex ToL SVL TL           TL/ToL     V    SC HL      HW     ED ED/HL

MNHN 1982.444 (HT)       Forêt d’Anatelo               697    588 109        0.16    229   58   18.5 11.3     2.4   0.13
MNHN 1978.1425 (PT)      Forêt d’Anatelo               560    469 91         0.16    233   56    –     –       –     –
UADBA (FGZC 1717)        Montagne des Français         704    610 94         0.13    235   46   17.8 10.5     2.3   0.13
ZSM 2053/2007            Montagne des Français         473    395 78         0.17    219   55   12.5 6.7      1.6   0.13
ZSM 1612/2008            Ampombofofo                   637    557 80         0.13    235   52   13.9 7.6      1.8   0.13
UADBA 00726              not available                 598    506 92         0.15    218   51    –     –       –      –
ZSM 1613/2008            Baie des Sakalava     juv.     400    345 55         0.14    234   50    9.7 5.3      1.4   0.14
A new black-bellied snake (Pseudoxyrhophiinae: Liophidium)                                                 177

frontals nearly quadratic. Loreal absent. Preocu-            dorsolateral stripe on dorsal scale rows 4-7,
lars single, two postoculars. Supraoculars elon-             and a diffuse dark vertebral stripe (3 dorsals
gate, posteriorly reaching to the posterior mar-             wide), composed of tiny irregularly shaped dark
gins of the postoculars. Frontal scale elongate,             markings on each scale.
triangular. Parietals triangular, very broad; ante-             Ventrals creamish white; a large black and
rior outer margins reaching down to the upper                somewhat irregularly shaped oval patch at cen-
portions of the lower postoculars. Upper labi-               ter of each scale; the large patches form a broad
als 7/7 but on left side an interspersed addi-               mid-ventral longitudinal stripe, reaching from
tional scale between upper labials 2 and 3; up-              the first onto the penultimate ventral; ultimate
per labials 3-4 in contact with eye. Lower labials           ventral, cloacal plate and subcaudals without
8/8, the first pair in contact behind the mental,            black central markings. Lateral edges of ven-
1-4 touching an anterior genial, 4-5 touching a              trals with tiny irregular dark markings, forming
posterior genial. Genials elongate, longer than              a diffuse longitudinal stripe; lateral markings on
broad; anterior genials broader than posterior.              subcaudals broad, covering the entire outer mar-
Almost all head shields (except parietals) with              gins of each scale.
tiny irregularly distributed papillae; on frontal               The overall dorsal life colouration appeared
scales only in irregular rows at the posterior               to be reddish brown (based on slides taken in
margins.                                                     the field, see also fig. 6, p. 431 in Glaw and
   We were not able to examine the dentition of              Vences, 2007). The lightly coloured areas at the
the new species comprehensively due to the del-              snout were creamish beige, the nuchal band and
icate nature of the only known specimen. How-                the light portions of the ventral side were bright
ever, we counted at least 23 maxillary teeth on              yellow in life.
the right maxilla, and noticed a small diastema,
                                                             Habitat. The holotype was collected during
probably due to missing teeth.
                                                             the day near a dirt road in the forest of Kirindy.
   After approximately three years in preser-
                                                             The vegetation at Kirindy consists of semi-
vative overall ground colouration brown with
                                                             open, deciduous dry forest. The snake was col-
small light and dark mottlings and longitudi-
                                                             lected as it crossed a sandy path at 7.00 a.m.
nal stripes. Dorsal head colouration brown, with
small and partly diffuse dark vermiculations.                Molecular relationships. The molecular tree
Rostral, internasals, anterior 4/5 of prefrontals            presented here (fig. 4) is based on cytochrome b
and most of the supraoculars creamish white                  DNA sequences of most Malagasy Liophidium
to light brown with some diffuse darker shades               species, and only misses L. apperti and L. tri-
and irregularly distributed tiny dark spots. Dark            lineatum. Monophyly of the included species of
dorsal head colouration posteriorly gradually                the genus is confirmed and strongly supported.
fading into a white, three dorsals wide nuchal               The sister group of Liophidium (made up by
band that ventrally connects with the white belly            the genus Liopholidophis; see Glaw, Nagy and
colouration. Nuchal band posteriorly sharply                 Vences, 2007; Glaw et al., 2007) is not sup-
edged by a three dorsals wide dark brown collar.             ported, and the same is true for other inter-
Lateral sides of the head dark brown; each up-               generic relationships, indicating that inclusion
per labial with an irregular, somewhat centered              of additional markers (Glaw et al., 2007) is nec-
large white marking. Gular region heavily mot-               essary to resolve these aspects of the topology.
tled with irregular large white and dark brown               Exallodontophis albignaci, for which molecu-
markings.                                                    lar data are here included for the first time,
   The dorsal colouration consists of a dark                 does not appear to be closely related to nei-
lower lateral stripe with slightly darker upper              ther Pseudoxyrhopus nor Liophidium and its
and lower edges on dorsal scale rows 1-3, a light            isolated position receives no relevant support.
178                                                                                                       M. Franzen et al.

Figure 4. Maximum likelihood tree based on cytochrome b sequences of species of Liophidium and other pseudoxyrhophiine
snakes. Numbers above branches are (from left to right) support values from bootstrap analyses (parsimony, 2000 replicates;
maximum likelihood, 100 replicates) and Bayesian posterior probabilities. Two species of Dromicodryas were used as
outgroup (not shown).

Within Liophidium, L. rhodogaster is placed as                  1958; Glaw and Vences, 1994). We have re-
most basal species, L. chabaudi is placed sister                examined the types of both taxa and conclude
to L. torquatum and L. maintikibo sister to L.                  that they strongly differ from L. maintikibo. The
therezieni. Hence, although several basal rela-                 holotype of Idiophis vaillanti var. extensa (SMF
tionships among genera are not sufficiently re-                 17152) has a high number of ventral scales
solved, the tree shows that Liophidium main-                    (250), three longitudinal rows of oval blotches
tikibo is firmly nested within Liophidium and                   on the ventral side and a dorsal colouration that
closely related to L. therezieni. The molecular                 consists of five well-defined narrow dark lon-
differentiation between these two species is of                 gitudinal lines alternating with strongly con-
of 11.8% uncorrected p-distance, at a similar                   trasting lightly coloured longitudinal bands. The
level as between other well-established species                 two syntypes of Wernerodakaria subpunctata
of pseudoxyrhophiine snakes.                                    (NMW 16860:1-2, female, male) also have high
Earlier available names. Besides current spe-                   numbers of ventral scales (240 and 228, respec-
cies as listed in the diagnosis, two nomina                     tively), are much larger than L. maintikibo (total
exist in the genus Liophidium that need to                      length 858 and 725 mm, respectively) and each
be considered as possible earlier names of                      possess a dorsal coloration of well-defined lon-
Liophidium maintikibo, namely Idiophis vail-                    gitudinal dorsal lines and bands, including five
lanti var. extensa Boettger, 1913 (type local-                  narrow dark lines, a light broad lateral band, and
ity: “Madagaskar”), and Wernerodakaria sub-                     a greyish broad vertebral band.
punctata (Werner, 1925) (substitute name for
Dakaria subpunctata according to Williams and                   Etymology. The species name is used as a
Wallach, 1989; type locality “Dakar, Senegam-                   noun in apposition and is composed of the
bien” [in error]), both currently seen as ju-                   Malagasy adjectiv “mainty”, meaning black,
nior synonyms of Liophidium vaillanti (Guibé,                   and “kibo”, meaning venter. It refers to the large
A new black-bellied snake (Pseudoxyrhophiinae: Liophidium)                                                         179

black central markings on the ventral scales of               Orangea region). All new localities are between
the new species.                                              20 and 230 m elevation.
                                                                 Meristic and mensural data of the new spec-
Distribution. Liophidium maintikibo is only                   imens are presented in table 2. The new spec-
known from the type locality. However, Mori                   imens resemble the holotype of L. therezieni
and Ikeuchi (2006: 42) depicted a snake from                  in most characters (see also table 2): Body
Ampijoroa (Mahajanga province, approx. 570                    approximately as high as wide; head slightly
km northeast of Kirindy) as a juvenile of L.                  wider than neck. Pupil round. Anterior edges
torquatum. This individual resembles the holo-                of internasals and posterior edges of prefrontals
type of L. maintikibo in most aspects of the dor-             rounded, convex. Loreal absent. Preocular sin-
sal and ventral colouration and may also repre-               gle, two postoculars. Temporals 1+2+3 on both
sent this new species.                                        sides. Usually 7/7 upper labials, with 3-4 touch-
                                                              ing the eye; two individuals (ZSM 2053/2007,
New data on Liophidium therezieni                             ZSM 1613/2008) with a 7/6 constellation (fu-
                                                              sion of right upper labials 5 + 6). Lower labi-
We obtained five new specimens of Liophid-                    als 8/8, the first pair in contact behind the men-
ium therezieni, mainly during extensive sur-                  tal, 1-4 touching an anterior genial, 4-5 touch-
veys of the amphibians and reptiles of the                    ing a posterior genial. Genials slightly longer
Montagne des Français area and the Ampom-                     than broad; anterior genials broader than poste-
bofofo region north of Anjiabe by volonteers                  rior. Dorsal scales smooth, in 17-17-17 rows at
of Frontier-Madagascar (e.g., D’Cruze et al.,                 midbody. Cloacal plate divided. See table 2 for
2007). All individuals were captured in more                  additional mensural and meristic data.
or less disturbed dry deciduous forests, either                  Life colouration (based on slides taken in the
in limestome (Tsingy) dry forest (Montagne des                field, see also fig. 5): Ground colouration of the
Français) or within dense scrub forest on heav-               heads in all specimens light brown, dorsally and
ily overgrown coastal dunes (Baie des Sakalava,               laterally dusted with dark brown, forming an in-

Figure 5. Liophidium therezieni from Baie des Sakalava (ZSM 1613/2008), showing similarities in dorsal colouration to L.
maintikibo.
180                                                                                      M. Franzen et al.

distinct dark head cap. The head cap covers the        men of P. melanogaster marojejyensis, from the
upper portions of all upper labials, preoculars,       Marojejy Massif in the North East (but see Ca-
postoculars, the frontal, supraoculars, and the        dle, 1999: 440, for problems with this locality).
parietals. A distinct cream patch covers the ros-      This prompted us to examine further material
tral, nasal, internasals as well as the prefrontals,   of P. melanogaster to assess its morphological
and a thin black postocular bar extends from           variability. Two specimens of this species were
the anterior of the eye to the anterior of upper       available to us, both collected by APR and col-
labial 7. The remaining portions of the upper          leagues in northern Madagascar, and both con-
and lower labials are immaculate white. A dis-         stituting new locality records for the species.
tinct cream nuchal collar (3 dorsals wide) bor-           UADBA 18586 (Ankarana Special Reserve;
dered by thin black lines is also present. Ground      see Appendix for comprehensive collection
colouration of dorsal scale rows light brown ex-       data): snout-vent length 247 mm, tail length
cluding the first three rows immediately fol-          43 mm (total length 290 mm); small rostral
lowing the light nuchal collar which share the         (not visible from above), quadratic internasals;
dark brown colouration of the head cap. Dor-           no loreal; prefrontals larger than internasals;
sum with five dark longitudinal lines: a broad         supraoculars large, roughly oval in shape; 7/7
lateral band on dorsal scale rows 1-3 (with scale      upper labials (3 + 4 in contact with eye); one
row 3 distinctly darker), a dark dorsolateral line     preocular, 3/2 postoculars; 1 + 2 + 3 tempo-
on dorsal scale row 6 and a middorsal line on          rals; head as broad as body (head width 5.1
scale row 9, which is distinctly darker than the       mm; head length 9.3 mm); eye small, 0.8 mm
other lines. The longitudinal lines start immedi-      in diameter (9% of head length); 17 dorsals,
ately behind the nuchal band and extend along          180 ventrals, cloacal plate divided, 42 subcau-
the entire length of the body, gradually fading        dal pairs. This specimen is reproduced in fig. 6,
on the anterior of the body and tail. Ground           and has also been shown by Glaw and Vences
colouration of ventral surfaces of the head, neck      (2007). UADBA 30054 (Andranotsimaty forest,
and body creamish white-grey, slightly irides-         Daraina Conservation Site) is a juvenile with
cent. Ventral surface of head dusted in places         a damaged head in poor state of preservation:
with dark grey. Venter and underside of tail usu-      snout-vent length 86.5 mm, tail length 29.5 mm
ally with two complete lateral rows (incomplete        (total length 116 mm), 17 dorsals, 187 ventrals,
in the juvenile ZSM 1613/2008) and one in-             cloacal plate divided, ca. 45 subcaudal pairs.
complete median row of irregular dark mark-            This specimen was collected under a rotten log
ings.                                                  in the morning around 10:00 a.m. within open
                                                       canopy dry transitional semi-deciduous forest.
New data on Pararhadinaea melanogaster                 The habitat was intensively disturbed by artisan
The new species described above, Liophidium            gold extraction and cattle grazing. When uncov-
maintikibo, bears a few characters, especially         ered, the snake tried to escape by burrowing into
the black colour on ventrals but not on sub-           the sandy soil.
caudals, that superficially resembles an enig-            The dorsal colouration of both specimens
matic species of pseudoxyrhophiine snake from          consists of two whitish, two light brown and
Madagascar, Pararhadinaea melanogaster. Be-            three dark brown stripes: the first dorsal scale
side a specimen with the unprecise local-              row is creamish white with tiny faint brown
ity information “Madagascar” (the holotype of          markings; a dark brown lower lateral stripe on
Rhabdotophis subcaudalis Werner, 1909), this           dorsal scale rows 2, 3 and the lower half of
species was so far known only from the type            row 4; a thin white line on the upper half of
specimen from Nosy Be in the Sambirano re-             dorsal scale row 4 and the lower half of row
gion of Madagascar, and from the type speci-           5; a narrow dark brown stripe on the upper
A new black-bellied snake (Pseudoxyrhophiinae: Liophidium)                                                181

Figure 6. Pararhadinaea melanogaster from Ankarana in life (UADBA 18586).

half of dorsal row 5 and lower half of row 6;                acters (Cadle, 1999: table 5), i.e., number of
two broad light brown to creamish paravertebral              maxillary teeth (Liophidium 26-33; Pararhad-
stripes on dorsal scale rows 6-8; a dark brown               inaea 13-14) and size of dentary teeth (Lio-
vertebral line on dorsal scale rows 8 and 9. The             phidium: all dentary teeth subequal; Pararhad-
ventrals are creamish white, each with a large,              inaea: posterior dentary teeth larger and more
centered, oval, black patch that covers most of              robust than anterior; less than 10 anterior den-
the scale. The dark blotches form a row from                 tary teeth). The comparably large number of
the first onto the penultimate ventral. Ultimate             at least 23 maxillary teeth in L. maintikibo is
ventral, cloacal plate and subcaudals without                nearly within the above given range for Lio-
black central markings.                                      phidium and clearly outside of the range of
                                                             Pararhadinaea. Molecular data also place L.
                                                             maintikibo near L. therezieni, and close to other
Discussion                                                   species such as L. torquatum, which have unan-
                                                             imously been assigned to the genus Liophidium
Liophidium maintikibo resembles Pararhadi-                   (e.g., Guibé, 1958; Domergue, 1984a; Ziegler
naea melanogaster (including P. m. maroje-                   et al., 1996; Cadle, 1999; Glaw and Vences,
jyensis) in several external characters: small to-           2007). Nevertheless, the formal allocation of
tal length (up to 290 mm in P. melanogaster),                L. maintikibo to Liophidium remains somewhat
a similar number of ventral and subcaudal scales             provisional due to the lack of L. trilineatum
(147-180 ventrals and 41-45 subcaudals in P.                 Boulenger, 1896 (the type species of Liophid-
melanogaster), lack of a loreal scale, only seven            ium according to Williams and Wallach, 1989)
upper labials, a dorsal pattern of five dark lon-            and Pararhadinaea melanogaster in the molec-
gitudinal stripes, a belly pattern consisting of a           ular analysis.
single row of large dark patches from the first to              Liophidium maintikibo is currently known
the penultimate ventral and an immaculate ven-               from a single specimen, L. therezieni from seven
tral tail.                                                   specimens, and Pararhadinaea melanogaster
   Cadle (1999) already stressed the close re-               from five specimens. In almost all cases only a
lationships of Liophidium and Pararhadinaea.                 single specimen of these species was collected
Both genera mainly differ in dentition char-                 from one locality. Nevertheless, our data indi-
182                                                                                                     M. Franzen et al.

cate that the extent of occurrence of these snakes            Domergue, C.A. (1984b): Notes sur les serpents de la région
is not necessarily small. P. melanogaster and                    malgache. 4. Le genre Pararhadinaea Boettger, 1898.
                                                                 Descriptions d’une espèce et d’une sous-espèce nou-
L. therezieni may in fact occur across northern                  velles. Bull. Mus. Natn. Hist. Nat., Paris 6: 149-157.
Madagascar, and L. maintikibo (if the Ampi-                   Glaw, F., Vences, M. (1994): A Fieldguide to the Amphib-
joroa locality is confirmed) across a wide range                 ians and Reptiles of Madagascar, 2nd Edition. Köln,
                                                                 Vences and Glaw Verlag.
in the West and North West. Whether the ex-                   Glaw, F., Vences, M. (2007): A Field Guide to the Am-
treme rareness of captures reflects real rareness                phibians and Reptiles of Madagascar, 3rd Edition. Köln,
of these snakes in their environments or secre-                  Vences and Glaw Verlag.
                                                              Glaw, F., Nagy, Z.T., Franzen, M., Vences, M. (2007): Mole-
tive habits remains to be studied.                               cular phylogeny and systematics of the pseudoxyrhophi-
                                                                 ine snake genus Liopholidophis (Reptilia, Colubridae):
                                                                 evolution of its exceptional sexual dimorphism and de-
Acknowledgements. We are grateful to Ruth Kühband-               scriptions of new taxa. Zoologica Scripta 36: 291-300.
ner who prepared the drawings and to Ivan Ineich, Gun-        Glaw, F., Nagy, Z.T., Vences, M. (2007): Phyloge-
ther Köhler and Franz Tiedemann for the loan of or access        netic relationships and classification of the Malagasy
to type specimens. Josef Friedrich Schmidtler kindly trans-      pseudoxyrhophiine snake genera Geodipsas and Comp-
ported material to Munich. We thank Frontier-Madagascar          sophis based on morphological and molecular data.
(The Society for Environmental Exploration) for the per-         Zootaxa 1517: 53-62.
manent loan of specimens collected during various surveys     Guibé, J. (1958): Les serpents de Madagascar. Mem. Inst.
and especially Steven Megson for his invaluable help in          Sci. Madagascar 12: 189-260.
the field. We are also grateful to the Malagasy authorities   Mori, A., Ikeuchi, I. (2006): A Photographic Guide to the
for issuing research and export permits. The new species         Reptiles and Amphibians of Ampijoroa. Kyoto Univer-
was found during a Tropical Biology Association Course           sity, Université d’Antanarivo, ANGAP, Durrell Wildlife
held in Kirindy Forest. We thank Rosie Trevelyan and Pi-         Conservation Trust.
otr Lukasik. ZTN acknowledges the financial support of the    Nagy, Z.T., Joger, U., Wink, M., Glaw, F., Vences, M.
Synthesys programme (6th FP of the EC).                          (2003): Multiple colonization of Madagascar and Soco-
                                                                 tra by colubrid snakes: evidence from nuclear and mi-
                                                                 tochondrial gene phylogenies. Proc. Roy. Soc. Lond. B
                                                                 270: 2613-2621.
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Domergue, C.A. (1984a): Notes sur les serpents de la ré-      Appendix: Comparative material examined
   gion malgache. 3. Description de trois espèces nouvelles
   rapportées au genre Liophidium Boulenger, 1896. Bull.      Liophidium therezieni: MNHN 1982.444 (holotype of
   Mus. Natn. Hist. Nat., Paris 5: 1109-1122.                 Liophidium therezieni), male, Antsiranana prov., Foret
A new black-bellied snake (Pseudoxyrhophiinae: Liophidium)                                                                  183

d’Anatelo (Ankarana), coll. Y. Therezien, 14.02.1966;               Liophidium vaillanti: NMW 16860:1 [female], NMW
ZSM 2053/2007, female, Antsiranana prov., Montagne des           16860:2 [male] (syntypes of Wernerodakaria subpunctata),
Français at 12◦ 19.59 S, 49◦ 20.60 E, 232 m elevation, coll.   “Dakar, Senegambien” (in error), coll. Zechmeister; SMF
K.G. Green, P. Cowling and several Frontier volunteers,          17152 (lectotype of Idiophis vaillanti var. extensa), male,
24.01.2006; UADBA uncatalogued (field number FGZC                “Madagascar”, coll. A. Voeltzkow, 1906.
1717), female, Antsiranana prov., Montagne des Français,            Pararhadinaea melanogaster: UADBA 18586, adult,
“Frontier base camp” approximately 1.5 km (air distance)         Antsiranana prov., Ankarana Special Reserve, “American
SW of Andavakoera at 12◦ 19.948 S, 049◦ 21.156 E, 200          Camp”, 2.6 km E Andrafiabe at 12◦ 55.9 S, 49◦ 03.4 E, 30
m elevation, coll. E. Randriamalala, 10.02.2006; ZSM             m elevation, coll. A.P. Raselimanana and M. Razafimpa-
1612/2008 (field number FGZC 1911), female, Antsiranana          hanana, 24.01.2001; UADBA 30054 (field number APR
prov., Ampombofofo region north of Anjiabe, “Frontier            06386), juvenile, Antsiranana prov., Diana region, Am-
base camp” at 12◦ 05.528 S, 049◦ 19.485 E, 28 m elevation,     bilobe district, Andranotsimaty forest (Daraina Conserva-
coll. R. Devas, 10.08.2006; ZSM 1613/2008 (field number          tion Site) at 13o 10.7 S, 49o 42.0 E, 150 m elevation, coll. A.
FGZC 1841), juvenile, Antsiranana prov., Baie des Sakalava       Raselimanana, 1994.
ca. 5 km SE of Ramena at 12◦ 16.338 S, 49◦ 23.237 E, 25 m
elevation, coll. S. Megson, 25.02.2008; UADBA 00726
(field number APR 03026), female, no locality data avail-        Received: April 18, 2008. Accepted: December 12, 2008.
able.
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