taxonID	type	description	language	source
4F58C651FF98634CFE5A2BCCB630FCCD.taxon	description	(Figures 1 a, b; 4 a; 5 a, d; 6 a, d; 7 a; 8 a)	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF98634CFE5A2BCCB630FCCD.taxon	materials_examined	Material examined Type material. Uganda. Holotype (here designated): adult ♂, CW 20.2, CL 13.7, CH 6.8, FW 6.8 mm, from upper reaches of Mbwa River in the Bwindi Impenetrable National Park, Kayonza area, Gombolola, Kigezi, Western Uganda, − 0.98333 ° S, 29.68333 ° E, in dense forest, clean river water, 14.4 ° C, 1615 m asl, coll. A. W. R. McCrae, 21 September 1962 (NHMUK reg. 2018. 1). Paratypes: three adult ♀♀, CW 22.6, CL 15; CW 21, CL 14.6; CW 20.6, CL 16 mm, two subadult ♂♂, CW 18.7, CL 13.3; CW 17.9, CL 12 mm, all same data as holotype (NHMUK reg. 2018. 2 – 4).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF98634CFE5A2BCCB630FCCD.taxon	diagnosis	Diagnosis Based on holotype (adult ♂ CW 20.2). Carapace: postfrontal crest faint but complete, lateral ends meeting anterolateral margins; epigastric crests rounded distinctly raised; exorbital, epibranchial teeth reduced to granules; anterolateral margin posterior to epibranchial tooth smooth (Figures 1 a, 4 a). Third maxilliped: ischium smooth, lacking sulcus (Figures 1 b, 4 a); s 3 / s 4 incomplete, comprising two long deep grooves on lateral margins, otherwise smooth; margins of s 4 low, not raised (Figure 1 b). Cheliped: dactylus (moveable finger) slim, highly arched, enclosing oval interspace, one medium tooth in mid-section, other teeth small; propodus (fixed finger) with large molar proximally (Figure 5 a); carpus distal tooth large, pointed, proximal tooth small, low (Figure 5 d); merus lined by series of small teeth, distal meral tooth large, pointed. G 1 terminal article: first third straight in line with longitudinal axis of subterminal segment, median part directed outward at 45 °, widened by raised rounded ventral lobe (Figure 6 d), tip curving sharply upwards (Figure 6 a, d).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF98634CFE5A2BCCB630FCCD.taxon	description	Description Based on holotype (adult ♂ CW 20.2). Carapace: medium height (CH / FW 1.0), front broad, measuring one-third CW (FW / CW 0.33); semi-circular, urogastric, cardiac, posterior, cervical carapace grooves all distinct; postfrontal crest complete, faint, lateral ends meeting epibranchial teeth; epigastric crests faint, median sulcus between crests short, forked posteriorly; exorbital, epibranchial teeth each reduced to granule; anterolateral margin between exorbital, epibranchial teeth smooth, curving slightly outward, lacking intermediate tooth; anterolateral margin posterior to epibranchial tooth smooth (Figure 1 a); vertical sulcus on carapace branchiostegal wall faint, meeting longitudinal sulcus, dividing carapace wall into three parts; suborbital margin granulated (Figure 1 b). Third maxilliped: exopod with long flagellum, ischium smooth lacking vertical groove (Figure 4 a). Epistomial tooth large, triangular, margins lined by large round granules (Figure 4 a). Mandible: palp two-segmented; terminal segment simple. Sternum: s 2 / s 3 deep, completely crossing sternum; s 3 / s 4 incomplete, comprising two long deep grooves on lateral margins, otherwise smooth; margins of s 4 low, not raised (Figure 1 b). Cheliped: adult male dactylus (moveable finger) slim, highly arched, enclosing oval interspace, one medium tooth in mid-section, other teeth small; propodus (fixed finger) with large molar proximally (Figure 5 a); carpus distal tooth large, pointed, proximal tooth small, low (Figure 5 d); merus lined by series of small granules, distal meral tooth large, pointed; superior surface granulated. Pleon: outline broadly triangular with straight margins. G 1: terminal article directed outward, proximal third straight in line with longitudinal axis of subterminal segment, median part directed outward at 45 °, widened by raised rounded ventral lobe, tip curving sharply upwards (Figure 6 a, d). G 2: terminal article long, flagellumlike (Figure 7 a). Small species, adult at CW 20 mm.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF98634CFE5A2BCCB630FCCD.taxon	distribution	Distribution	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF98634CFE5A2BCCB630FCCD.taxon	materials_examined	Uganda. This species is known only from a single locality in the upper reaches of the Mbwa River in the Bwindi Impenetrable National Park, Kayonza area, Gombolola, Virunga Massif, Western Uganda (− 0.98333 ° S, 29.68333 ° E; Figure 8 a). Type locality Upper reaches of Mbwa River in the Bwindi Impenetrable National Park, Kayonza area, Gombolola, Kigezi, Western Uganda (− 0.98333 ° S, 29.68333 ° E), in dense forest, clean river water, 14.4 ° C, 1615 m asl. Conservation status An IUCN conservation assessment of P. bwindi sp. nov. has not yet been carried out, but given the fact that this species is known from only six specimens that are all from a single locality in a protected area (Bwindi Impenetrable National Park), and that no threats are known, it would probably be regarded as Data Deficient.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF98634CFE5A2BCCB630FCCD.taxon	biology_ecology	Ecology This species was collected from a high-altitude locality (1615 m asl) in dense transitional / intermediate montane forest from the clean, cool waters (14.4 ° C) of the upper reaches of Mbwa River in the Bwindi Impenetrable National Park. This national park is part of the Lake Victoria Basin Freshwater Ecoregion 521 (Thieme et al. 2005; Abell et al. 2008). The ← Mbwa River is a tributary of the Ishasha River that flows north into Lake Rutanzige which is part of the Nile River basin. This remote national park is mostly accessible only on foot and is part of the Bwindi Impenetrable Forest that borders the Virunga National Park in the DRC. This is the first record of an endemic species of freshwater crab from the Bwindi Impenetrable National Park.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF98634CFE5A2BCCB630FCCD.taxon	etymology	Etymology The new species is named for the Bwindi Impenetrable National Park which lies in southwestern Uganda where this species was first collected. The specific epithet bwindi is used as a Latin noun in apposition. The vernacular name is the Bwindi crab.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF98634CFE5A2BCCB630FCCD.taxon	discussion	Remarks Potamonautes bwindi sp. nov. differs from P. kivu sp. nov. and P. rwenzori sp. nov. in that the distal tooth on the merus of the cheliped is large and pointed followed by a row of small teeth (Figure 1 a, b) [vs either a small and pointed distal meral tooth (P. kivu sp. nov.), or a blunt and low distal meral tooth (P. rwenzori sp. nov.), followed by a row of granules in P. kivu sp. nov. and P. rwenzori sp. nov.; Figures 2 b and 3 b]; and the cheliped dactylus of the adult male is highly arched and encloses a broad oval interspace when closed (Figure 5 a) (vs a cheliped dactylus of the adult male that is slightly curved, not arched, and encloses a long narrow interspace in P. kivu sp. nov. and P. rwenzori sp. nov.; Figure 5 b, c). Potamonautes bwindi sp. nov. differs from other, similar small-bodied species of freshwater crabs found in Uganda in that s 3 / s 4 (Figure 2 a) comprises two long deep grooves at the margins and is otherwise faint or absent (vs two short shallow grooves at the margins in P. elgonensis Cumberlidge and Clark, 2010 a and P. kanstyore Cumberlidge and Clark, 2017); the third maxilliped ischium is smooth and lacks a vertical sulcus (Figure 2 a) (vs a third maxilliped ischium with a deep vertical sulcus in P. loveni (Colosi, 1924), P. mutandensis, P. rukwanzi Corace, Cumberlidge and Garms, 2001, and P. williamsi Cumberlidge and Clark, 2010 a); the cheliped merus has a large pointed distal meral tooth (Figure 1 a) (vs a small, low distal meral tooth in P. elgonensis, P. imatongensis Cumberlidge and Clark, 2016; P. loveni, P. morotoensis Cumberlidge and Clark, 2016; P. rukwanzi and P. williamsi); the distal tooth on the cheliped carpus is small, broad and low (Figure 5 d) (vs a large, pointed distal tooth in the cheliped carpus in P. busungwe Cumberlidge and Clark, 2017, P. entebbe Cumberlidge and Clark, 2017; P. imatongensis and P. kantsyore Cumberlidge and Clark, 2017); and the tip of the G 1 terminal article curves sharply upwards (Figure 6 a, d) (vs a G 1 terminal article with either a straight or a slightly upturned tip in P. busungwe, or a straight tip in P. amalerensis (Rathbun, 1935), P. busungwe, P. elgonensis, P. entebbe, P. imatongensis, P. loveni, P. morotoensis and P. mutandensis (cf. Cumberlidge and Clark 2010 a, 2010 b, 2016, 2017; Cumberlidge and Meyer 2011).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF96634EFDEC2A73B630F9A1.taxon	description	(Figures 2 a, b, 4 b, 5 b, e, 6 b, e, 7 b, 8 b)	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF96634EFDEC2A73B630F9A1.taxon	materials_examined	Material examined Type material. Rwanda. Holotype (here designated): adult ♂, CW 24.9, CL 18.7, CH 7.8, FW 7.8 mm, from Gisenyi, Lake Kivu, − 1.698122 ° S, 29.251734 ° E, 1471 m asl (NHMUK reg. 2018. 5, formerly NMU TRW August 1972), coll. A. G. Goodall, 1972. Paratypes: two adult ♀♀ CW 18.3, CL 13.0, CH 7.2, FW 6.9 (ovigerous), CW 15.5, CL 12.4, CH 6.3, FW 5.5; two subadult ♀♀ (both with widened pleon incompletely covering sternum) CW 14.8, CL 11.7, CH 5.5, FW 5.5; CW 14.0, CL 10.4, CH 5.0, FW 5.0; two juvenile ♀♀ (both with slim pleon) CW 10.5, CL 8.5, CH 4.5, FW 4.5; CW 10.2, CL 7.6, CH 4.0, FW 4.0; subadult ♂ CW 15.1, CL 10, CH 4.8, FW 4.8; all same data as holotype (NHMUK reg. 2018. 98 – 104). Other material. Rwanda. Potamonautes sp. (not P. kivu. sp. nov.): juvenile ♂ (both chelipeds and both gonopods small and under-developed) CW 19.6, CL 15.3, CH 5.4, FW 6.8 mm, from Gisenyi, Lake Kivu, − 1.698122 ° S, 29.251734 ° E (NHMUK reg. 2018.105, formerly NMU TRW 1972.08), coll. A. G. Goodall, 1972.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF96634EFDEC2A73B630F9A1.taxon	diagnosis	Diagnosis Based on holotype (adult ♂ CW 19.8). Carapace: postfrontal crest faint, lateral ends meeting anterolateral margins; epigastric crests rounded, distinctly raised; exorbital, epibranchial teeth each reduced to granule; anterolateral margin posterior to epibranchial tooth smooth (Figures 1 b, 4 b). Third maxilliped: ischium with very faint shallow vertical sulcus (Figures 1 b, 4 b); s 3 / s 4 incomplete, comprising two short shallow grooves on lateral margins, otherwise smooth; margins of s 4 low, not raised (Figure 1 b). Cheliped: dactylus (moveable finger) slim, arched, enclosing oval interspace, teeth medium, small; propodus (fixed finger) with medium, small teeth; carpus distal tooth low, broadly triangular, proximal tooth small, low (Figure 5 b); merus lined by series of small granules, distal meral tooth small, pointed. G 1: terminal article directed outwards, proximal third straight in line with longitudinal axis of subterminal segment, median part directed outwards at 45 °, widened by raised rounded ventral lobe (Figure 6 e), tip curving sharply upwards (Figure 6 b, e).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF96634EFDEC2A73B630F9A1.taxon	description	Description Based on holotype (adult ♂ CW 19.8 mm). Carapace: outline transversely oval, medium height (CH / FW 1.0), front broad measuring one-third CW (FW / CW 0.33); postfrontal crest faint, lateral ends meeting epibranchial teeth; epigastric crests rounded, distinctly raised, median sulcus between crests short, forked posteriorly; semi-circular, urogastric, cardiac, posterior, cervical carapace grooves all distinct, shallow. Exorbital, epibranchial teeth each reduced to granule; anterolateral margin between exorbital, epibranchial teeth with small granules, lacking intermediate tooth; anterolateral margin posterior to epibranchial tooth smooth (Figure 1 b); suborbital margin faintly granular; vertical sulcus on carapace branchiostegal wall faint, meeting longitudinal sulcus, dividing carapace wall into three parts. Third maxilliped: exopod with long flagellum, ischium with faint shallow vertical sulcus (Figures 2 b, 4 b). Epistomial tooth large, triangular, margins lined by granules (Figure 2 b). Mandible: palp two-segmented; terminal segment simple. Sternum: s 2 / s 3 deep, running horizontally across sternum; s 3 / s 4 incomplete, comprising two short shallow grooves on lateral margins, otherwise smooth; margins of s 4 low, not raised; s 4 / e 4, s 5 / e 5, s 6 / e 6, s 7 / e 7 grooves all either faint or not visible (Figure 2 b). Cheliped: dactylus (movable finger) slim, arched, enclosing oval interspace, teeth medium, small; tip of dactylus overlapping tip of propodus (fixed finger); propodus with medium, small teeth (Figure 5 b); carpus distal tooth pointed, triangular, proximal tooth small, low (Figure 5 e); merus lined by series of small teeth, distal meral tooth larger, pointed. Pleon: outline broadly triangular with straight margins. G 1: terminal article directed outward, proximal third directed outwards at 45 ° to longitudinal axis of subterminal segment, median part widened by raised rounded ventral lobe (Figure 6 e), tip curving sharply upwards (Figure 6 b, e). G 2: terminal article long, flagellum-like (Figure 7 b). Small-sized species, adult at CW 15.5 mm.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF96634EFDEC2A73B630F9A1.taxon	distribution	Distribution This species is known only from three specimens collected from a single locality near the town of Gisenyi on the shores of Lake Kivu in Rwanda (Figure 8 b).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF96634EFDEC2A73B630F9A1.taxon	materials_examined	Type locality The type locality is Lake Kivu at Gisenyi, Rwanda (− 1.698122 ° S, 29.251734 ° E; Figure 8 b). Conservation status An IUCN conservation assessment of P. kivu sp. nov. has not yet been carried out, but given the fact that this species is known from only three specimens from a single locality, and no specific threats are known, it would probably be regarded as Data Deficient. In addition, this species is not found in a protected area.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF96634EFDEC2A73B630F9A1.taxon	etymology	Etymology The new species is named for Lake Kivu, Rwanda in the Albertine Rift Valley, where this species was first collected. The specific epithet kivu is used as a Latin noun in apposition. The vernacular name is the Kivu crab.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF96634EFDEC2A73B630F9A1.taxon	biology_ecology	Ecology Lake Kivu (1463 m asl) is a small (100 km long by 50 km wide), deep lake (480 m) situated in the Western Rift Valley as part of the Albertine Rift which is divided by the border between the DRC and Rwanda, with the large Idjwi Island in Lake Kivu lying in the DRC. Lake Kivu now drains southwards into Lake Tanganyika via the River Ruzizi (but historically Lake Kivu drained north into Lake Rutanzige before being blocked by volcanic activity in the mid-Pleistocene; Worthington and Lowe- McConnell 1994). Little is known about the habitat and ecology of P. kivu sp. nov. Lake Kivu is part of Lake Victoria Basin Freshwater Ecoregion 521 (Thieme et al. 2005; Abell et al. 2008). Four other species of freshwater crabs are known from Lake Kivu (Cumberlidge and Meyer 2011); two are endemic (P. idjwiensis and P. bourgaultae) and two (P. lirrangensis and P. mutandensis) have a wider distribution. Potamonautes kivu sp. nov. is the fifth species known to occur in this lake.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF96634EFDEC2A73B630F9A1.taxon	discussion	Remarks Potamonautes kivu sp. nov. differs from other, similar small-bodied species of freshwater crabs from the Albertine Rift Valley and other parts of Uganda in that s 3 / s 4 is reduced to two short faint shallow sulci at the margins (Figure 2 b) (vs two long deep sulci at the margins in P. amalerensis, P. busungwe, P. bwindi sp. nov., P. entebbe, P. imatongensis, P. loveni, P. rwenzori sp. nov., P. morotoensis, P. mutandensis and P. rukwanzi; Corace et al. 2001; Cumberlidge and Clark 2010 a, 2010 b, 2016, 2017; Cumberlidge and Meyer 2011); the third maxilliped ischium is smooth and lacks a sulcus (Figure 4 b) (vs an ischium with a distinct vertical sulcus in P. aloysiisabaudiae, P. emini (Hilgendorf, 1892), P. loveni, P. mutandensis, P. rukwanzi, P. rwenzori and P. williamsi); and the tip of the G 1 terminal article curves sharply upwards (Figure 6 b, e) (vs a G 1 terminal article whose tip is either straight or only slightly upturned in P. amalerensis, P. busungwe, P. elgonensis, P. entebbe, P. imatongensis, P. loveni and P. morotoensis; Cumberlidge and Clark 2010 a, 2010 b, 2016, 2017; Cumberlidge and Meyer 2011). It is of interest that a small juvenile male belonging to an unidentified species of Potamonautes (NHMUK reg. 2018.105, formerly NMU TRW 1972.08) was also collected from Lake Kivu together with the holotype and paratypes of P. kivu sp. nov. described here. Although it was not possible for us to identify this specimen, it is clear from its undeveloped abdomen, gonopods and chelipeds at CW 19.6 mm that it belongs to a much larger species than P. kivu sp. nov. (one which would be adult at this size). Furthermore, the cheliped and carapace characters of the unidentified specimen (although under-developed) indicate that it does not belong to P. lirrangensis, the only species known to occur in Lake Kivu that grows to a large size (cf. Cumberlidge and Meyer 2011).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF8B6352FE3A29ADB305FD50.taxon	description	(Figures 3 a, b, 4 c, 5 c, f, 6 c, f, 7 c, 8 c)	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF8B6352FE3A29ADB305FD50.taxon	materials_examined	Material examined Type material. Democratic Republic of the Congo. Holotype (here designated): adult ♂, CW 24.3, CL 16.7, CH 8.9, FW 7.3 mm, from River Talya, Maya Moto, near Mutsora (a station in the Virunga National Park, formerly the Albert National Park), western foothills of the Rwenzori Mountains, 0.316728 ° N, 29.750125 ° E 1100 – 1200 m asl, date and coll. unknown (NHMUK reg. 2018. 6, pres. the Royal Belgian Institute of Natural Sciences, Brussels, Belgium). Paratypes: 2 adult ♂♂, CW 21.4, CL 15.3; CW 23.2, CL 16.1, 2 adult ♀♀, CW 24, CL 17.5; CW 21.3, CL 15.9 mm, same details as holotype (NHMUK reg. 2018. 7 – 8), 0.316728 ° N, 29.750125 ° E. Other material. Uganda. Adult ♂, CW 25.8, CL 17.5 mm; three subadult ♂♂, CW 19.2, CL 14.3; CW 18.8, CL 13.8; CW 17.8, CL 12.7; three adult ♀♀, CW 24.3, CL 17.1; CW 21.4, CL 16.1; CW 20.5, CL 15.2, Rwenzori Mountains, 0.239081 ° N, 29.942965 ° E, coll. unknown, 1 November 1952 (NHMUK reg. 2018. 9 – 15).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF8B6352FE3A29ADB305FD50.taxon	diagnosis	Diagnosis Carapace: medium height (CH / FW 1.2); exorbital, epibranchial teeth each reduced to granule, postfrontal crest complete, faint medially, lateral ends well defined, meeting epibranchial teeth; anterolateral margin posterior to epibranchial tooth finely serrate, almost smooth (Figure 3 a); vertical sulcus on carapace branchiostegal wall faint, meeting longitudinal sulcus, dividing carapace wall into three parts not meeting anterolateral margin (Figure 4 c). Third maxilliped: ischium with vertical sulcus; s 3 / s 4 complete, deep. Cheliped: inferior margins of merus with series of small granules, distal meral tooth small; propodus (fixed finger) of major cheliped with large teeth along cutting edge, largest molars proximal; dactylus (movable finger) with series of small teeth along cutting edge interspersed by two medium-sized teeth in middle, not arched, enclosing long narrow interspace when closed (Figure 5 c); carpus distal tooth large, pointed, proximal tooth small, pointed (Figure 5 f). G 1: terminal article straight, entire terminal article directed outwards at 45 ° to longitudinal axis of subterminal segment, median part widened slightly by low slim ventral lobe (Figure 6 f), tip slightly upturned (Figure 6 c, f).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF8B6352FE3A29ADB305FD50.taxon	description	Description Carapace: medium height (CH / FW 1.2); front broad, measuring one-third CW (FW / CW 0.3); semi-circular, urogastric, cardiac, posterior, cervical carapace grooves all faint; postfrontal crest complete, faint, lateral ends well defined meeting epibranchial teeth; epigastric crests distinct, median sulcus between crests short, forked posteriorly; exorbital, epibranchial teeth each reduced to granule; anterolateral margin between exorbital, epibranchial teeth smooth, curving slightly outward, lacking intermediate tooth; anterolateral margin posterior to epibranchial tooth smooth (Figure 3 a); vertical sulcus on carapace branchiostegal wall distinct, incomplete, beginning at longitudinal sulcus not meeting anterolateral margin, dividing carapace branchiostegal wall into three parts; suborbital margin smooth. Third maxilliped: exopod with long flagellum, ischium with distinct vertical sulcus. Epistomial tooth: large, triangular, margins lined by faint granules (Figure 3 b). Mandible: palp two-segmented, terminal segment simple. Sternum: s 2 / s 3, s 3 / s 4 deep, wide, both completely crossing sternum; s 4 / e 4, s 5 / e 5, s 6 / e 6, s 7 / e 7 all faint (Figure 3 b). Cheliped: propodus (fixed finger) of adult male with series of small, medium sized teeth along cutting edge interspersed by two large pointed teeth in middle; dactylus (movable finger) with series of small teeth along cutting edge interspersed by two medium sized teeth in middle, not arched, enclosing long narrow interspace when closed (Figure 5 c); inferior margins of merus with series of small rounded teeth, distal tooth small, low; distal tooth on inner margin of carpus large, pointed, proximal tooth very small, granular (Figure 5 f), superior surface of merus granulated. Pleon: outline broadly triangular with straight margins. G 1: terminal article straight, entire terminal article directed outwards at 45 ° to longitudinal axis of subterminal segment, median part widened slightly by low slim ventral lobe, tip slightly upturned (Figure 6 c, f). G 2: terminal article long, flagellum-like (Figure 7 c). Small-sized species, adult size range between CW 20.5 – 25.8 mm.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF8B6352FE3A29ADB305FD50.taxon	distribution	Distribution This species is found in the Rwenzori Mountains from two localities, one in the western foothills of the Rwenzori Mountains in the DRC, and one in the central and eastern parts of the Rwenzori Mountains in Uganda (Figure 8 c).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF8B6352FE3A29ADB305FD50.taxon	materials_examined	Type locality DRC, River Talya, Maya Moto, near Mutsora, a station in the Virunga National Park, formerly the Albert National Park, western foothills of the Rwenzori Mountains (0.3166667 ° N, 29.75 ° E), 1100 – 1200 m asl, in the intermediate / transitional forest zone. The Rwenzori Mountains lie on the border between Uganda and the DRC and reach 5109 m asl, which is high enough to support permanent snowcaps and glaciers despite its close proximity to the equator (Plumptre et al. 2007). This mountain range is one of the sources of the Nile River and includes two national parks: the Rwenzori Mountains National Park and the Virunga National Park.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF8B6352FE3A29ADB305FD50.taxon	biology_ecology	Ecology The Rwenzori Mountains lie in the DRC and Uganda in the southern part of Upper Nile Ecoregion 522 (Thieme et al. 2005; Abell et al. 2008) which includes Lake Albert and the River Semuliki in the Western Rift Valley. Most of this ecoregion lies to the north of these mountains in the drainage basin of the River Nile in South Sudan, Sudan and Ethiopia, and includes the vast Sudd swamplands. Both of the known localities where P. rwenzori sp. nov. occurs (in the western foothills and in the central and eastern side of the Albertine Rift Valley) are in protected areas (the Rwenzori Mountains National Park and the Virunga National Park). The Rwenzori Mountains National Park is in Kabarole, Kasese and Bundibugyo Districts in Western Uganda and is a UNESCO World Heritage Site that borders the Virunga National Park in the DRC. Despite the apparent protection offered by these two national parks there are potential threats from agricultural encroachment and collection of wood in the parks, with the result that the Rwenzori Mountains National Park is also on the List of World Heritage in Danger (Plumptre et al. 2007). Conservation status An IUCN conservation assessment of P. rwenzori sp. nov. has not yet been carried out, but given the fact that this species is known from only a few specimens from two localities it will probably be eventually regarded as Data Deficient. Each of the localities where this species is known to occur is in a protected area.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF8B6352FE3A29ADB305FD50.taxon	etymology	Etymology The new species is named for the Rwenzori Mountains where this species was first collected. The specific epithet rwenzori is used as a Latin noun in apposition. The vernacular name is the Rwenzori crab.	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
4F58C651FF8B6352FE3A29ADB305FD50.taxon	discussion	Remarks Potamonautes rwenzori sp. nov. differs from P. bwindi sp. nov. and P. kivu sp. nov. in that the major cheliped propodus has large teeth along the cutting edges in the proximal region (Figure 5 c) (vs a cheliped propodus that has medium and small teeth along the cutting edges in P. bwindi sp. nov. and P. kivu sp. nov.; Figure 5 a, b); and the tip of the G 1 terminal article is straight or only slightly upturned (Figure 6 c, f) (vs a sharply upturned terminal article tip in P. bwindi sp. nov. and P. kivu sp. nov.; Figure 6 a, b, d, e). Potamonautes rwenzori sp. nov. differs from other, similar small-bodied species of freshwater crabs from Uganda in that s 3 / s 4 is a long, deep sulcus that completely crosses the sternum (Figure 3 b) (vs two short shallow sulci at the margins and otherwise smooth in P. elgonensis and P. kanstyore) (Cumberlidge and Clark 2010 a, 2017); the third maxilliped ischium has a deep vertical sulcus (Figure 4 c) (vs a smooth ischium lacking a sulcus in P. amalerensis, P. busungwe, P. elgonensis, P. entebbe, P. imatongensis, P. kantsyore and P. morotoensis; cf. Cumberlidge and Clark 2010 a, 2016, 2017); the cheliped carpus distal tooth is large and pointed (Figure 5 f) (vs a small and low cheliped carpus tooth in P. amalerensis, P. elgonensis, P. loveni, P. morotoensis and P. williams; cf. Cumberlidge and Clark 2010 a, 2010 b, 2016); and the cheliped dactylus is broad, not highly arched, and encloses a long rectangular interspace (Figure 5 c) (vs a highly arched dactylus enclosing a broad oval interspace in P. amalerensis, P. busungwe, P. elgonensis, P. entebbe, P. imatongensis, P. loveni, P. morotoensis, P. mutandensis and P. williamsi; cf. Cumberlidge and Clark 2010 a, 2010 b, 2016, 2017; Cumberlidge and Meyer 2011). Potamonautes rwenzori sp. nov. is also found in the same region of Uganda as P. aloysiisabaudiae and the two species share a number of carapace characters such as an extremely low exorbital tooth, an epibranchial tooth that is reduced to a small granule, and a smooth anterolateral margin immediately behind the epibranchial tooth. The two species can be distinguished in that P. rwenzori sp. nov. is a small species that is adult at CW 24 mm (vs P. aloysiisabaudiae which is adult at CW 45 mm), and the margin of the merus of the cheliped of P. rwenzori sp. nov. is granulated with a small but distinct distal meral tooth (Figure 5 f) (vs P. aloysiisabaudiae which has a cheliped merus margin that is smooth with a distal meral tooth reduced to a granule); and the distal tooth of the cheliped carpus is large and pointed (Figure 5 f) (vs a low blunt cheliped carpus tooth in P. aloysiisabaudiae); and the ischium of the third maxilliped is smooth (Figure 4 c) (vs an ischium with a distinct vertical groove in P. aloysiisabaudiae). General remarks Potamonautes bwindi sp. nov., P. kivu sp. nov. and P. rwenzori sp. nov. share a number of characters with each other and several additional species in this genus from East Africa. For example, the three new species described here all share an extremely low exorbital tooth and an epibranchial tooth that is reduced to a small granule; all have a smooth anterolateral margin immediately behind the epibranchial tooth (Figures 1 a, 2 a, 3 a); and all are adult at a small carapace size (CW 19.8 – 24.0 mm). Ugandan crabs that share this suite of characters include P. amalerensis, P. busungwe, P. elgonensis, P. entebbe, P. imatongensis, P. kantsyore, P. loveni, P. morotoensis, P. mutandensis, P. rukwanzi and P. williamsi (cf. Corace et al. 2001; Cumberlidge and Clark 2010 a, 2010 b, 2016, 2017; Cumberlidge and Meyer 2011). Until the present study, only three species of freshwater crabs were known from the Albertine Rift Valley: two large and abundant species of river crabs (P. aloysiisabaudiae and P. niloticus), and one small lake-living species (P. mutandensis) (Cumberlidge and Meyer 2011). Potamonautes aloysiisabaudiae is widespread throughout western Uganda and its range includes the Virunga and Rwenzori Mountains and the associated rivers and lakes that flow north into the Nile River basin (Bott 1955; Cumberlidge unpubl. data). Potamonautes niloticus is one of the most widespread species in Africa and is found throughout the Nile River basin from Rwanda to Egypt (Cumberlidge 2009), while P. mutandensis occurs in lakes from southern Uganda to Lake Kivu in Rwanda (Cumberlidge and Meyer 2011).	en	Cumberlidge, Neil, Clark, Paul F. (2018): Albertine Rift Valley endemics: three new species of freshwater crabs (Brachyura: Potamoidea: Potamonautidae) from Uganda, the Democratic Republic of the Congo, and Rwanda. Journal of Natural History 52 (25 - 26): 1637-1656, DOI: 10.1080/00222933.2018.1480812, URL: http://dx.doi.org/10.1080/00222933.2018.1480812
