Ptychadena trinodis (Boettger, 1881)

COLLECTION MATERIAL. — Burkina Faso • 4♀ (SVL 52.5-55.2 mm); Ouagadougou; 12.38011°N, – 1.51100°W; 300 m a.s.l.; VIII.1966; Père Terrible leg.; MNHN- RA-1995.3233, 1995.3234, 1995.3235, 1995.3236 • 5 ♀ (SVL 48.1-56.9 mm), 1 ♂ (SVL 51.8 mm); Loumana; 10.58001°N, – 5.35044°W; 330 m a.s.l.; 3.IX.1970; J.J. Morère leg.; MNHN-RA-1996.3931, 1996.3942, 1996.3943, 1996.3944, 1996.3945, 1996.3946 • 2 ♀ (SVL 54.1-57.2 mm), 1♂ (SVL 55.7 mm); a trail between Bobo-Dioulasso and Kofila; 11.33755°N, – 3.92852°W; 290 m a.s.l.; 7.XI.1970; J. J. Morère leg.; MNHN-RA-1996.3939, 1996.3940, 1996.3941 • 2 subadults (SVL 30.2-34.7 mm); Samba; 12.70144°N, – 2.40391°W; 290 m a.s.l.; 2.I.1963; M. Lamotte leg.; MNHN-RA-1993.3572, 1993.5679 .

FIELD MATERIAL. — Burkina Faso • 1 ♀ (SVL 55.5 mm); Deux Balés National Park, downstream from the Soumbou dam; 11.69872°N, – 2.79738°W; 260 m a.s.l.; 8.XI.2017; H. J. Ayoro leg.; under a stone near water body; hand capture • 1 ♂ (SVL 53.6 mm); Arly National Park; 11.57044°N, 1. 45211°E; 190 m a.s.l.; 12. VI.2018; same collector as for preceding; near a small water body on a trail; hand capture • 1 ♂; Koubri, downstream from Nabazana dam; 12.20319°N, – 1.35105°W; 280 m a.s.l.; 17.VII.2017; H. J. Ayoro & A. Ohler leg.; in a paddy field; acoustic report • 1 ♀ (SVL 52.1 mm); Comoé-Léraba Forest, Kotokoi swampy valley; 9.82802°N, – 4.62727°W; 230 m a.s.l.; 3.VIII.2018; same collectors as for preceding; near a small water pool; hand capture • 1 subadult (SVL 42.4 mm); Baboro swampy valley; 9.92521°N, – 4.5739°W; 230 m a.s.l.; 4.VIII.2018; same collectors as for preceding; on a trail; hand capture • 1 ♀ (SVL 59.1 mm), 6 subadults (SVL 35.7-45.2 mm); Folonzo village swampy valley; 9.88803°N, – 4.61969°W; 230 m a.s.l; 6.VIII.2018; same collectors as for preceding; around a vegetable garden; hand capture • 18 subadults (SVL 25.0- 44.1 mm); the flooded zone of Yakouta dam; 14.06117°N, – 0.13181°W; 270 m a.s.l.; 26.VIII.2018; H. J. Ayoro leg.; under grasses; hand capture • 4 subadults (SVL 19.1-46.4 mm); the edge of Dori pond, Toroodi; 14.00607°N, – 0.02846°W; 280 m a.s.l.; 24-27.VIII.2018; same collector as for preceding; under grasses; hand capture • 4 subadults (SVL 31.1- 46.3 mm); the edge of N’Djomga pond; 14.07225°N, – 0.04862°W; 265 m a.s.l.; 25.VIII.2018; same collector as for preceding; under grasses near water body; hand capture • 3 ♀ (SVL 52.3-57.3 mm); the edge of Fafo dam; 11.33470°N, – 3.01947°W; 300 m a.s.l.; 10.XI.2018; same collector as for preceding; in paddy field; hand capture • 1 ♀ (SVL 59.8 mm); Djindjerma, close to Koti; 11.38211°N, – 3.05145°W; 310 m a.s.l.; 1.XI.2018; same collector as for preceding; around a drink water well; hand capture .

LITERATURE REPORTS. — Burkina Faso • Gourma province, Fada N’gourma; 12.06051°N, 0.34913°E; 300 m a.s.l. (Mohneke 2011; Mohneke et al. 2011) • Ganzourgou province, Mogtedo; 12.31844°N, – 0.83601°W; 280 m a.s.l. (Mohneke 2011; Mohneke et al. 2011) • Zorgho; 12.2483°N, – 0.6278°W; 300 m a.s.l.; I-III.2008 (Mohneke 2011; Mohneke et al. 2011) .

DESCRIPTION. — 54 specimens studied. Stout and robust frogs, with a moderately pointed snout, strong and long limbs. An inner and an external metatarsal tubercle present and very protruding as indicated by Rödel (2000) and Sánchez-Vialas et al. (2017). Webbing formula: I 0 - 1 ½ II 0 - 1 III 0 - 1 ½ IV 1 ½ - 0 V. Four pairs of continuous dorsal ridges extending along the entire back. In life and alcohol, dorsal colouration from brown to dark grey. Presence of a wide white, yellow in life, vertebral line in all specimens. Species usually with a more granular dorsal skin, in comparison to other members of this genus (Rödel 2000).

HABITAT. — Specimens were captured in grasses near water bodies in Comoé-Léraba Forest and Deux Balé National Park; on a trail near a water body in Arly National Park; under humid gasses at Dori pond and Yakouta dam banks. Ptychadena trinodis was one of the most abundant Ptychadena species at savannah ponds during the rainy season (Nago et al. 2006). The species is then virtually restricted to small or tiny water bodies which often lack vegetation (Guibé & Lamotte 1957; Lamotte 1969; SchiØtz 1967; Perret 1981; Rödel 2000). This species is distributed from West Africa east to northern Democratic Republic of Congo (Rödel 2000; Padial & De La Riva 2004; Sánchez-Vialas et al. 2017; Böhme & Heath 2018).