,26 /Six New Species of African Clawed Frog (Xenopus)R. C. Bell, T. Ogombet, U. Eyagui, P. Endazokou; NCSM 78881, juvenile, same collectors, N 0.0426 E 12.2983, 21 October 2011. Republic of Cameroon: Centre Region: NMP6V 74568, adult female, Ebogo, N 3.3913 E 11.4663, 628 m, 17 October 2009, coll. V. Gvozd ; Est Region: NMP6V 74718, subadult female, Kika, N 1.9419?E 15.6269? 337 m, 30 May 2010, coll. V. Gvozd , O. Kopeck? fnins.2015.00094 Sud Region: MHNG 2644.58 (AMNH 17288), male laboratory animal descended from animals collected in Nkoemvone, N 2.8800?E 11.1500? 575 m, unknown date, coll. H. R. Kobel; ZFMK 87790?, sex unknown, Nkoelon, Campo Region, N 2.3500?E 10.6167? 76 m, October 2007, coll. M. Barej, J. Wurstner; Democratic Republic of Congo: CAS 250558, female, Bas-Congo Province, Malemba, S 5.83? E 12.57?(estimated), 150 m, Pan-RAS-IN-1 site collection date unknown, coll. D. Rungger (specimen from captive population originally housed in Laboratoire de G ique Animale et V ale, Universit?de Gen e; possibly wild caught). Referred Specimens.–Democratic Republic of Congo: Bas-Congo Province, IRSNB (PM106), probably male, Luki Reserve, S 5.5963?E 13.1603? 220 m, 19 June 2012, IRSNB (PM119), male, Tsumba-Kituti, S 5.6581?E 13.1995? 255 m, 20 June 2012, coll. V. Gvozd , Z. C. Kusamba, M. M. G. Collet, Z. T. Nagy. Diagnosis.–Xenopus mellotropicalis is a tetraploid species with a burst-type call that exhibits all of the morphological features of subgenus Silurana described above (Fig 11). It differs from other species of Silurana in the following ways: from all species by unique nucleotide substitutions in mitochondrial and autosomal DNA (Figs 1 and 2 and S1 and S2); from X. calcaratus by more pulses in the call, more defined lateral-line plaques, and generally lacking prominent dark spots on the dorsum (common in the Bioko population of X. calcaratus); from X. 3-Methyladenine molecular weight epitropicalis by lacking a biphasic call, and having shorter interpulse intervals; from X. tropicalis by being tetraploid, by lacking a trill-type call and having less intensity modulation in the call, and generally lacking prominent dark spots on the dorsum. Xenopus mellotropicalis also differs from X. tropicalis and X. epitropicalis by the peptides present in its norepinephrinestimulated skin secretions [70]. Description of the holotype.–Medium-sized (SVL 48 mm), moderately robust male (Table 1, Figs 6 and S3 5); rostral tip blunt and rounded in dorsal view; eyes not projecting beyond margins of orbit in dorsal view and projecting slightly beyond dorsal margin of head in lateral view; journal.pone.0158910 subocular tentacle short, length less than half eye diameter; eye diameter 42 of interorbital distance, 83 of eye arial distance, and 1.4 times distance from naris to rostral tip; internarial distance 46 of interorbital distance; no vomerine teeth. Skin smooth; small prominent asperities on snout and scattered over much of body and limbs; small tubercles across plantar surface; punctiform but well separated lateral-line plaques around eye; lateral-line plaques most prominent on dorsal and lateral surfaces and extending onto the ventral surface, and oral and ventral plaques difficult to observe due to similarity of coloration with venter; counts of lateral-line rows as follows: orbital?11, oral?12, medial?17, lateral?17, ventral?13; male nuptial pads are well developed appearing as dark keratinous patches on ventral surface of the arm and forearm, and extending along metacarpals and digits. Relative lengths of fingers: II.,26 /Six New Species of African Clawed Frog (Xenopus)R. C. Bell, T. Ogombet, U. Eyagui, P. Endazokou; NCSM 78881, juvenile, same collectors, N 0.0426 E 12.2983, 21 October 2011. Republic of Cameroon: Centre Region: NMP6V 74568, adult female, Ebogo, N 3.3913 E 11.4663, 628 m, 17 October 2009, coll. V. Gvozd ; Est Region: NMP6V 74718, subadult female, Kika, N 1.9419?E 15.6269? 337 m, 30 May 2010, coll. V. Gvozd , O. Kopeck? fnins.2015.00094 Sud Region: MHNG 2644.58 (AMNH 17288), male laboratory animal descended from animals collected in Nkoemvone, N 2.8800?E 11.1500? 575 m, unknown date, coll. H. R. Kobel; ZFMK 87790?, sex unknown, Nkoelon, Campo Region, N 2.3500?E 10.6167? 76 m, October 2007, coll. M. Barej, J. Wurstner; Democratic Republic of Congo: CAS 250558, female, Bas-Congo Province, Malemba, S 5.83? E 12.57?(estimated), 150 m, collection date unknown, coll. D. Rungger (specimen from captive population originally housed in Laboratoire de G ique Animale et V ale, Universit?de Gen e; possibly wild caught). Referred Specimens.–Democratic Republic of Congo: Bas-Congo Province, IRSNB (PM106), probably male, Luki Reserve, S 5.5963?E 13.1603? 220 m, 19 June 2012, IRSNB (PM119), male, Tsumba-Kituti, S 5.6581?E 13.1995? 255 m, 20 June 2012, coll. V. Gvozd , Z. C. Kusamba, M. M. G. Collet, Z. T. Nagy. Diagnosis.–Xenopus mellotropicalis is a tetraploid species with a burst-type call that exhibits all of the morphological features of subgenus Silurana described above (Fig 11). It differs from other species of Silurana in the following ways: from all species by unique nucleotide substitutions in mitochondrial and autosomal DNA (Figs 1 and 2 and S1 and S2); from X. calcaratus by more pulses in the call, more defined lateral-line plaques, and generally lacking prominent dark spots on the dorsum (common in the Bioko population of X. calcaratus); from X. epitropicalis by lacking a biphasic call, and having shorter interpulse intervals; from X. tropicalis by being tetraploid, by lacking a trill-type call and having less intensity modulation in the call, and generally lacking prominent dark spots on the dorsum. Xenopus mellotropicalis also differs from X. tropicalis and X. epitropicalis by the peptides present in its norepinephrinestimulated skin secretions [70]. Description of the holotype.–Medium-sized (SVL 48 mm), moderately robust male (Table 1, Figs 6 and S3 5); rostral tip blunt and rounded in dorsal view; eyes not projecting beyond margins of orbit in dorsal view and projecting slightly beyond dorsal margin of head in lateral view; journal.pone.0158910 subocular tentacle short, length less than half eye diameter; eye diameter 42 of interorbital distance, 83 of eye arial distance, and 1.4 times distance from naris to rostral tip; internarial distance 46 of interorbital distance; no vomerine teeth. Skin smooth; small prominent asperities on snout and scattered over much of body and limbs; small tubercles across plantar surface; punctiform but well separated lateral-line plaques around eye; lateral-line plaques most prominent on dorsal and lateral surfaces and extending onto the ventral surface, and oral and ventral plaques difficult to observe due to similarity of coloration with venter; counts of lateral-line rows as follows: orbital?11, oral?12, medial?17, lateral?17, ventral?13; male nuptial pads are well developed appearing as dark keratinous patches on ventral surface of the arm and forearm, and extending along metacarpals and digits. Relative lengths of fingers: II.