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Orthochromis indermauri sp. nov. Orthochromis sp. “Chomba” Indermaur 2014 Holotype. ZSM 46853 (1, ex ZSM 43080, 54.0 mm SL), Zambia, Lufubu River, below last series of rapids near Chomba village, ~ 25.5 km (air distance) from confluence with Lake Tanganyika and 20 km (air distance) south of Sumbu (-8.687010/30.556273) Paratypes. ZSM 46855 (13, 35.8–68.9 mm SL), Zambia, Lufubu River, Lower Lufubu at Chomba Village, ~ 30 km from confluence with Lake Tanganyika, Northern Province (-8.686376/30.563983). — ZSM 46854 (1, 61.2 mm SL), Zambia, Lufubu River, Lower Lufubu at Chomba Village, ~ 30 km from confluence with Lake Tanganyika, Northern Province (-8.686376/30.563983). — ZSM 43083 (4, 45.6–59.4 mm SL), collected with holotype. — ZSM 43080 (2, 42.0– 43.1 mm SL), collected with holotype. — ZSM 44283 (3, 50.8-63.5 mm SL), Zambia, Lufubu River, Lower Lufubu at Chomba Village, ~ 30 km from confluence with Lake Tanganyika, Northern Province (-8.686376/30.563983). — MRAC 2018-006 -P-0001-0002 (2, ex ZSM 44283, 56.8– 51.9 mm SL) Zambia, Lufubu River, Lower Lufubu at Chomba village, ~ 30 km from confluence with Lake Tanganyika, Northern Province (-8.686376/30.563983). — MRAC 2018-006 -P-0003-0008 (6, 43.3–64.1 mm SL), Zambia, Lufubu River, Lower Lufubu at Chomba village, ~ 30 km from confluence with Lake Tanganyika, Northern Province (-8.686376/30.563983). Diagnosis. Orthochromis indermauri is distinguished from all all species currently placed in Orthochromis (sensu de Vos & Seegers, 1998) except O. torrenticola, by having hypurals 1 and 2 clearly separated or separated by distinct seam (vs. always fused). It is further distinguished from Malagarasi- Orthochromis species, except O. mazimeroensis, O. malagaraziensis, and O. rubrolabialis, by having fewer caudal vertebrae (14–15 vs. 16–18) and total vertebrae (28–29 vs. 30–32). It is also distinguished from O. luichensis, O. malagaraziensis, O. mazimeroensis, O. mosoensis by having more inner series of teeth in upper jaw (3–5 vs. 1–2). Moreover, it differs from O. kasuluensis by having fewer anal-fin rays (7–9 vs. 10); from O. malagarazienisis by having more scales between upper lateral line and dorsal-fin origin (5–7 vs. 3–4) and by having more ceratobranchial gill rakers (8–11 vs. 6–7); from O. mazimeroensis by having more abdominal vertebrae (14–15 vs. 12–13); from O. mosoensis and O. rubrolabialis by having more ceratobranchial gill rakers (8–11 vs. 5–7) and total gill rakers (11–15 vs. 8–10); from O. uvinzae by having fewer horizontal line scales (25–29 vs. 30–32), fewer dorsal-fin spines (17–18 vs. 19– 20) and by position of pterygiophore supporting last dorsal-fin spine (vertebral count: 16–17 vs. 18–19). It is distinguished from O. kalungwishiensis, O. luongoensis, and O. torrenticola by having fewer horizontal line scales (28–29 vs. 30–32) and by having fewer caudal vertebrae (14–15 vs. 17–18). Further, it differs from O. luongoensis and O. machadoi by having fewer series of scales on cheek (0–1 vs. 2–5); from O. kalungwishiensis by having fewer total vertebrae (28–29 vs. 31–33). It is distinguished from S. neodon by having fewer horizontal line scales (28–29 vs. 30–31), more circumpeduncular scales (16 vs. 12), fewer caudal vertebrae (14–15 vs. 16–17), fewer total vertebrae (28–29 vs. 30–32), fewer dorsal-fin rays (8–10 vs. 11–12) and by having hypurals 1 and 2 clearly separated or separated by distinct seam (vs. fused). It differs from H. snoeksi by having fewer scales on cheek (0–1 vs. 2–3), fewer horizontal line scales (25–29 vs. 30–31), more abdominal vertebrae (14–15 vs. 13), fewer caudal vertebrae (14–15 vs. 17), fewer total vertebrae (28–29 vs. 30), more anal-fin rays (7–9 vs. 5–6), more dorsal-fin spines (17–18 vs. 16), more ceratobranchial gill rakers (8–11 vs. 6) and total gill rakers (11–15 vs. 9); from H. bakongo by having more inner series of teeth (3–5 vs. 1–2), more dorsal-fin spines (17–18 vs. 14–15) and in position of pterygiophore supporting last dorsal-fin spine (vertebral count: 16–18 vs. 13–14); from H. moeruensis by having hypurals 1 and 2 clearly separated or separated by distinct seam (vs. always fused). Meristic values of O. indermauri overlap with those of H. vanheusdeni but is distinguished by differences in head mask (e.g. nostril stripe present vs. absent; caudal corner of cheek with blackish element vs. no such element present) and by size and colouration of eggspot-like maculae on anal fin (e.g. deep red centre vs. orange centre in H. vanheusdeni). It is distinguished from O. mporokoso and O. katumbii by having fewer caudal vertebrae (14–15 vs. 16–17), fewer total vertebrae (28–29 vs. 30–31) and by having hypurals 1 and 2 and hypurals 3 and 4 clearly separated or separated by distinct seam (vs. always fused). Further from O. mporokoso by having fewer series of scales on cheek (0–1 vs. 2– 4); from O. katumbii by having fewer horizontal line scales (25–29 vs. 30–31). It is distinguished from O. kimpala by having fewer series of scales on cheek (0–1 vs. 3–4) and by having more dorsal-fin spines (17–18 vs. 15–16). Meristic values of O. indermauri overlap with those of O. gecki but is distinguished by having a wider interorbital width (13.5–18.2 vs. 9.6–12.9 %HL). Description. Morphometric measurements and meristic characters are based on 21 out 32 type specimens. Values and their ranges are presented in Table 6. For general appearance see figure 7. Maximum length of wild caught specimens 68.9 mm SL. Moderately slender species with maximum body depth (24.5–29.9 % SL) slightly posterior or at level of first dorsal-fin spine, decreasing rather gradually towards caudal peduncle (but decreasing relatively quick just before caudal peduncle). Caudal peduncle rather short and deep (ratio of caudal peduncle length to depth: 1.2–1.4). Head length almost one third of standard length. Dorsal-head profile moderately curved without prominent nuchal gibbosity. Eye diameter always larger than interorbital width. Jaws slightly retrognathouswith lower jaw shorter than upper jaw. Posterior tip of maxilla not reaching anterior margin of orbit but slightly before. Lips not noticeably enlarged or thickened. Two separate lateral lines. Squamation. Flank above and below lateral lines covered with cycloid scales, even in smaller specimens. Belly and chest covered by deeply embedded minute scales giving appearance of being scaleless. Ventro-anterior area of pectoral fin with small, deeply embedded cycloid scales. Chest to flank transition with small, embedded cycloid scales. Snout scaleless. Interorbital region with minute, deeply embedded cycloid scales. Nape and occipital region covered with minute to small, embedded cycloid scales becoming slightly larger towards occipital region. Cheek appears scaleless, but rarely small deeply embedded cycloid scales present just below eye; 0–1 scale rows on cheek. Cycloid scales on operculum of variable size (small to medium) and mainly of circular shape; opercular blotch only on anterior margin covered by medium sized scales, main area of opercular blotch scaleless. 5–7 scales on horizontal line from edge of postero-dorsal angle of operculum to anterior edge of operculum. Upper lateral line scales 20–23 and lower lateral line 7–11. Horizontal line scales 27–29. Caudal fin with 0–2 pored scales. Upper and lower lateral lines separated by two scales. 3–5 scales between upper lateral line and dorsal-fin origin. Anterior part of caudal fin covered with 2–3 vertical rows of small cycloid scales with median scales being slightly larger; scaled area of caudal fin extended posteriorly with interradial scales (approximately up to two thirds of caudal fin). Sixteen scales around caudal peduncle. Jaws and dentition. Anterior teeth of outer row of upper and lower jaw bicuspid to subequally bicuspid, large and very densely set; teeth smaller towards corner of mouth, more widely set and becoming unicuspid (rarely tricuspid or subequally bicuspid teeth present on upper jaw near corner mouth). Individual bicuspid teeth with not expanded brownish crown, cusps (tips pointed) slightly compressed and narrowly set, and neck slender. Outer row of upper jaw with 42–59 teeth and outer row of lower jaw with 26–45 teeth (specimens: 35.8–68.9 mm SL); larger specimens generally with more teeth. Inner upper jaw with 3–5 tooth rows and 3–4 rows (rarely 2) in lower jaw, all with small tricuspid teeth. Lower pharyngeal bone (Fig. 7) of single dissected paratype (ZSM 46854, 61.2 mm SL) about as wide as long with anterior keel about 0.6 times length of dentigerous area. Dentigerous area of lower pharyngeal bone about 1.5 times wider than long, with 11+11 teeth (empty tooth-sockets included) along posterior margin and eight teeth along midline. Anterior pharyngeal teeth (towards keel) bevelled and slender; teeth posterior row larger than anterior ones, bevelled (bicuspid; well-developed major and minor cusp). Largest teeth medially in posterior row. Teeth along midline slightly larger than more lateral ones. ......continued on the next page Gill rakers. Total gill raker count 11–15, with 2–4 epibranchial, one angle, and 8–10 ceratobranchial gill rakers. Anteriormost ceratobranchial gill rakers smallest increasing in size towards cartilaginous plug (angle). Anterior gill rakers on ceratobranchial generally unifid, sometimes bifid towards cartilaginous plug. Gill raker on cartilaginous plug shorter than longest ceratobranchial gill raker and epibranchial gill rakers further decreasing in size. Fins. Dorsal fin with 17–18 spines and with 8–10 rays. First dorsal-fin spine always shortest. Dorsal-fin base length between 56.9–65.4 % SL. Posterior end of dorsal-fin rays extending slightly beyond caudal fin base; posterior tip of anal fin reaching slightly before or at caudal fin base. Caudal fin outline subtruncate and composed of 27–29 rays (16 principal caudal-fin rays and 11–13 procurrent caudal-fin rays). Anal fin with 3 spines (3rd spine longest) and 7–9 rays. Anal-fin base length between 16.7–21.9 % SL. Pectoral fin with 14 to 15 rays and length between 19.7–25.6 % SL; longest pectoral ray not reaching or in rare cases almost reaching level of anus (ending approximately 1-2 flank scale widths in front of it). First upper and lower pectoral-fin rays very short to short. Pelvic fin with 1 st spine thickly covered with skin and 5 rays. Pelvic fin base at same level pectoral fin base. Longest pelvic-fin ray not reaching or in rare cases almost reaching anus (ending approximately 1-2 flank scale widths in front of it). Vertebrae and caudal fin skeleton. 28–29 total vertebrae (excluding urostyle element), with 14–15 abdominal and 14–15 caudal vertebrae. Pterygiophore supporting last dorsal-fin spine inserted between neural spines of 16th and 17th or 17th and 18th vertebra (counted from anterior to posterior). Pterygiophore supporting last anal-fin spine inserted between haemal spines of 15th and 16th or 16th and 17th vertebra, rarely between rips of 14th and haemal spine of 15th vertebra (N=1). Single predorsal bone (=Supraneural bone) present. Hypurals 1 and 2 either clearly separated or separated by distinct seam but never fused into single seamless unit. Hypurals 3 and 4 either fused into single seamless unit or separated by distinct seam. Colouration in life (based on field photographs of adult specimens). Body ground colouration brownish yellow, towards belly more yellowish; dorsum brownish yellow to pale brown; chest below pectoral fins yellow becoming reddish ventrally; belly yellow. Dorsal head surface pale brown dorsally with reddish speckles; ethmoidal area pale brown and densely speckled with reddish spots, especially in dominant males (Indermaur 2014). Iris reddish posteriorly, yellow dorsally, remaining greyish. Upper lip dark grey anteriorly sometimes with reddish speckles; lower lip light greyish, yellowish posteriorly. Cheek pale brown becoming yellowish towards corner mouth and mental area; blackish pear-shaped blotch at caudal-ventral corner, expanding to anterior extension of midlateral band. Branchiostegal membrane along operculum yellow becoming whitish to pale pinkish ventrally. Operculum yellow with black opercular spot, which is fused with anterior extension of midlateral band which is ending just anterior of the eye. Broad blackish lachrymal stripe between orbit and caudal corner of upper lip. A relatively faint greyish nostril stripe, sometimes covered by many reddish speckles. Relatively wide blackish interorbital stripe. Blackish supraorbital stripe connected with nape band. Nape band ending slightly anterior of dorsal-fin origin and fused with dorso-lateral band. Dorso-lateral band slightly below dorsal fin base and visible up to third or fourth anterior vertical bar. Relatively thin midlateral band ending with dark blotch just posterior base caudal fin. 7–9 blackish vertical bars crossing midlateral band and extending onto dorsal fin almost to fin margin; anterior-most vertical bar (just behind operculum) less intensive than remaining bars. Vertical bars wider than space between them. Dorsal-fin membrane yellow without maculae, skin/membrane of first three dorsal-fin spines black creating the appearance of a broad black oblique band between 1 st and 4th spine. Margin of spiny part dorsal fin with fine black outline and red (distally) and transparent submarginal band; rayed part of dorsal fin lacks transparent submarginal band. Anal fin yellow; margin greyish outlined. Posterior half of anal fin with deep-red maculae on membrane (between last four anal-fin rays); maculae elongated proximally becoming more rounded distally (maculae not to fin margin but ending slightly before). In general, these maculae resemble egg-spots: large deep red centre surrounded by faint greyish ring then by ill-defined transparent ring. Caudal fin yellow with deep red maculae as described for anal fin but only with roundish maculae. Caudal fin with reddish marginal band with narrower bluish submarginal band; another submarginal band of red maculae (intensity varies). Outer caudal-fin rays outlined in black. Pectoral fin yellow to orange. Pelvic fin yellowish with dark greyish anterior margin spanning spine and first two rays. Juvenile colouration in life. (based on tank-raised juveniles of approximately 20 to 30 mm SL; Fig. 9). Ground colouration greyish to beige. Patterns and head mask as described for adults. No reddish speckles present. Dorsal and midlateral band, greyish vertical bars on flank as described for adults. Dorsal fin hyaline to beige with vertical flank bars extending onto fin. Anal, caudal, pectoral and pelvic fin hyaline. Colouration in alcohol. Colouration and melanin patterns similar to live specimens, but due the preservation procedure of specimens, i.e., first formalin fixation, transfer to 75 % EtOH etc., specimens tend to lose original colouration (especially melanin patterns more intense than in live specimens). Overall body ground colouration pale brownish to pale yellowish; chest and belly beige to yellowish. Branchiostegal membrane greyish-beige to greyish-brown. Dorsal head surface pale brownish; ethmoidal region greyish-brown. Upper lip brownish and lower lip beige. Cheeks beige to brownish; pear-shaped blotch on lower caudal corner of cheek greyish-brownish and less prominent than in living specimens. Operculum greyish and with opercular spot as described above. Head mask and mid- and dorso-lateral band and vertical bars brownish to greyish. Dorsal fin light greyish except dark grey skin/membrane of first three anterior spines, remaining fin with black margin; extensions of vertical bars on dorsal fin dark grey. Anal fin light greyish; margin outlined in dark grey; no maculae visible. Caudal fin light greyish and margins outlined in black; some thin blackish streaks on membrane between rays may be present. Pectoral fin light grey. Pelvic fin light grey, skin/membrane of pectoral spine and first two rays greyish. Distribution and biology. Orthochromis indermauri is only known from the lower reaches of the Lufubu River (Zambia), the third largest tributary of Lake Tanganyika (Fig. 1). Several cascades and waterfalls seem to represent insurmountable barriers to the upstream movement of the lake ichthyofauna hence the fish communities of the upper and lower reaches are clearly distinct. The Upper Lufubu has faunistic similarities to the Congo and Zambezi systems while the Lower Lufubu shows faunistic influences of Lake Tanganyika (Koblmüller et al. 2012). At the type locality the Lufubu River is rocky with some patches of sand and gravel, about 20 meters wide and on average 50 cm deep (Fig. 8). The water temperature varies throughout the year, 23 °C was measured in July and 28.1 °C in November, the pH ranged between 8.0–8.55, and electrical conductivity around 29 µS (Indermaur 2014, pers. com. Bernd Egger). O. indermauri is benthic-rheophilic and prefers stretches of fast flowing water where it is found between and among large rocks or patches of gravel. No stomach contents were examined, however, underwater observations indicate it scrapes aufwuchs from the substrate and forages between rocks and patches of sand and gravel (Indermaur 2014, pers. obs. FS). Orthochromis indermauri is a maternal mouthbrooder. Females in captivity have comparatively small clutches of between 17 and 21 fry (two spawns, pers. com. Adrian Indermaur). Etymology. The species name indermauri honours the Swiss ichthyologist Dr. Adrian Indermaur, who was the first to document this new species with underwater photographs, videos, and with aquarium observations, thereby contributing to a large extent to our knowledge of behavior and ecology of this species.

Orthochromis mporokoso sp. nov. Orthochromis sp. ���Kasinsha������ Schedel et al. 2014 Holotype. ZSM 46840 (59.04 mm SL, ex ZSM 41443), Zambia, Kasinsha stream north of Luwinga affluent to Lake Mweru (-9.4894/30.5769). Paratypes. ZSM 41429 (9, 34.0��� 74.48 mm SL), Zambia, Mutoloshi stream above Kapuma Falls at Mporokoso on road Mukunsa-Luwinga (-9.3889/30.0956). ��� ZSM 41443 (4, 40.9���63.2 mm SL), collected with holotype.��� MRAC 2018-006 -P-0009-0011 (3, 48.7���51.9 mm SL) Zambia, Mutoloshi stream above Kapuma Falls at Mporokoso on road Mukunsa-Luwinga (-9.3889/30.0956). Additional material. ZSM 46841 (1, ex 41429, 54.28 mm SL; specimen with deformed jaws), Zambia, Mutoloshi stream above Kapuma Falls at Mporokoso on road Mukunsa-Luwinga (-9.3889/30.0956). Differential diagnosis. Orthochromis mporokoso can be readily distinguished from all species currently placed in Orthochromis species of the genus Orthochromis and O. sp. ���Igamba��� from the Malagarasi drainage system by having more scale rows on cheek (2���4 vs. 0���1). Furthermore, O. mporokoso can be distinguished from O. kasuluensis, O. mosoensis, and O. rugufensis by having more scales on operculum (3���4 vs. 0���2); from O. kasuluensis by having fewer total vertebrae (30 vs. 31���32); from O. rugufuensis by fewer dorsal-fin spines (16���17 vs. 19); from O. mazimeroensis by more horizontal line scales (29���30 vs. 26���28), more abdominal vertebrae (14 vs. 12���13) and more total vertebrae (30 vs. 28���29); from O. rubrolabialis and O. uvinzae by fewer dorsal-fin spines (16���17 vs. 18���20); it has more total gill rakers than O. rubrolabialis (10���12 vs. 8���9) and differs in position of pterygiophore supporting last dorsal-fin spine (vertebral count: 16 vs. 17���18). It differs from O. uvinzae additionally by having fewer scales between upper lateral line and dorsal-fin origin (4���5 vs. 6���8), fewer abdominal vertebrae (14 vs. 15���16), fewer total vertebrae (30 vs. 31���33), position of pterygiophore supporting last dorsal-fin spine (vertebral count: 16 vs. 18���19), position of pterygiophore supporting last anal-fin spine (vertebral count: 14- 15 vs. 16���17); from O. luongoensis and O. torrenticola by having fewer caudal vertebrae (16 vs. 17���18) and total vertebrae (30 vs. 31���33); from O. kalungwishiensis by having fewer total vertebrae (30 vs. 31���33) and fewer horizontal line scales (29���30 vs. 31���32); from O. torrenticola additionally by having fewer anal-fin spines (3 vs. 4) and position of pterygiophore supporting last anal-fin spine (vertebral count: 14���15 vs. 16���17). It can be distinguished from O. stormsi and O. polyacanthus by having fewer scales between upper lateral line and dorsal-fin origin (4���5 vs. 6���9). In addition, it is distinguished from O. stormsi by having more horizontal line scales (29���30 vs. 26���28), more total vertebrae (30 vs. 28���29) and fewer total gill rakers (10���12 vs. 13���15); from O. polyacanthus by having more series of scales on cheek (2���4 vs. 0), fewer dorsal-fin spines (16���17 vs. 18���20) and in position of pterygiophore supporting last dorsal-fin spine (vertebral count: 16 vs. 17���18) as in position of pterygiophore supporting last anal-fin spine (vertebral count: 14���15 vs. 16���17). Meristic values of O. mporokoso overlap with those of O. machadoi, but it can be readily distinguished by having more vertical bars on flanks (13���15 vs. 9���10), which moreover extend mainly ventrally; those of O. machadoi extend mainly dorsally. In addition, it is distinguished in head mask pattern, i.e. V -shape nostril stripe in O. mporokoso vs. straight nostril stripe in O. machadoi; cheek stripe present vs. absent in O. machadoi. It differs from Schwetzochromis neodon by having more circumpeduncular scales (16 vs. 12), fewer inner series of teeth (1���3 vs. 4���6) and fewer dorsal-fin rays (9���10 vs. 11���12). It differs from H. bakongo and H. moeruensis by having more horizontal line scales (29���30 vs. 26���28), more caudal vertebrae (16 vs. 12���15) and more total vertebrae (30 vs. 26���29). Additionally, it is distinguished from H. moeruensis by having more upper lateral line scales (21���23 vs. 19���20); from H. bakongo by having more dorsal-fin spines (16���17 vs. 14���15) and in position of pterygiophore supporting last dorsal-fin spine (vertebral count: 16 vs. 13���14); and from H. snoeksi it is distinguished by having more abdominal vertebrae (14 vs. 13), fewer caudal vertebrae (16 vs. 17), more anal-fin rays (7���9 vs. 5���6), more total gill rakers (10���12 vs. 9), and in position of pterygiophore supporting last dorsal-fin spine (vertebral count: 16 vs. 15) and position pterygiophore supporting last anal-fin spine (vertebral count: 14���15 vs. 13). Meristic values of O. mporokoso overlap with those of H. vanheusdeni, but it lacks eggspots, has a nostril stripe (vs. absent in H. vanheusdeni), exhibits a cheek stripe (vs. absent in H. vanheusdeni), and has higher number of vertical bars on flank (13���15 vs. 6���7). It differs from herein newly described species O. kimpala by having fewer scales between upper lateral line and dorsal-fin origin (4���5 vs. 6���7); from O. indermauri by having more series of scales on the cheek (2���4 vs. 0���1), more caudal vertebrae (16 vs. 14���15), and more total vertebrae (30 vs. 28���29). Meristic values of O. mporokoso overlap with those of O. katumbii but former differs by having more vertical bars on flank (13���15 vs. 7���9) and by head mask pattern (i.e.: cheek stripe present vs. absent in O. katumbii). Meristic values of O. mporokoso overlap with those of O. gecki but former is distinguished by having much wider interorbital (15.3���19.5 vs. 9.6���12.9 % HL) and by lacking eggspots on anal fin vs. present in O. gecki. Description. Morphometric measurements and meristic characters are based on 17 type specimens and one additional deformed specimen. Values and their ranges are presented in Table 2. For general appearance see figure 3. Maximum length of wild caught specimens 74.5 mm SL. Moderately slender species with maximum body depth (24.7���29.3 % SL) at level of dorsal-fin origin, slowly decreasing towards caudal peduncle. Caudal peduncle rather elongated and moderately deep (ratio of caudal-peduncle length to depth: 1.5���2.3). Head length almost one third of standard length. Dorsal head profile slightly curved without prominent nuchal gibbosity. Eye diameter larger than interorbital width. Jaws isognathous or slightly retrognathous. Posterior tip of maxilla not reaching anterior margin of orbit but ending slightly before. Lips not noticeably enlarged or thickened. Two separate lateral lines. Squamation. Flank above and below lateral lines covered with comparatively large ctenoid to cycloid scales, especially in large specimens only few scales of ctenoid appearance. Anterior dorsal and ventral flank area covered by cycloid scales. Belly with comparatively small cycloid scales. Chest covered with even smaller cycloid scales compared to belly squamation; chest to flank transition with larger cycloid scales. Snout scaleless up to anterior margin of orbit. Interorbital, nape, and occipital region with medium sized cycloid scales. Cheeks covered by small cycloid scales; 2���4 scale rows on cheek. Cycloid scales on operculum of variable size (small to medium sized) and shape (ovoid to circular); opercular blotch partially covered by medium sized scales, but posterior margin scaleless. 3���4 scales on horizontal line starting from edge of postero-dorsal angle of operculum to anterior edge of operculum. Upper lateral line scales 21���23 and lower lateral line 9���11. Horizontal line scales 29���30. Caudal fin with 0���2 pored scales. Upper and lower lateral lines separated by two scales. 3���5 scales between upper lateral line and dorsal-fin origin. Anterior part of caudal fin covered with 4���5 vertical columns of small cycloid scales with median scales slightly larger; scaled area of caudal fin extended posteriorly especially at upper and lower area with minute, interradial scales (approximately up to one third of caudal fin). Sixteen scales around caudal peduncle. Jaws and dentition. Anterior bicuspid teeth of outer row in both upper and lower jaw large and closely set; posterior teeth becoming almost subequally bicuspid; towards corner of mouth teeth smaller and less closely set, may become unicuspid or weakly bicuspid especially in upper jaw. Individual bicuspid teeth with minimally expanded brownish crown, cusps (major cusp with almost horizontal edge) uncompressed and moderately widely set, and neck moderately slender to stout. Outer row upper jaw with 31���44 teeth and outer row lower jaw with 23��� 33 teeth (specimens: 34.0���59.0 mm SL). Larger specimens generally with more teeth. Two to three (rarely one) inner upper and lower jaw tooth rows with small tricuspid teeth. Lower pharyngeal bone (Fig. 3) of single dissected paratype (ZSM 41429, 59.8 mm SL) about 1.3 times wider than long with short anterior keel about 0.4 times length dentigerous area. Dentigerous area of lower pharyngeal bone about 1.5 times wider than long, with 10+10 teeth along posterior margin and 7���8 teeth along midline. Anterior pharyngeal teeth (towards keel) bevelled and slender; those of posterior row larger than anterior ones, bevelled (bicuspid; well-developed major and minor cusp). Largest teeth medially situated in posterior row. Teeth along midline slightly larger than more lateral ones. Gill rakers. Total gill raker count 10���12, with two epibranchial, one angle, and 7���9 ceratobranchial gill rakers. Most anterior ceratobranchial gill rakers very small, increasing in size towards cartilaginous plug (angle). Gill raker in angle slightly shorter than longest ceratobranchial raker and epibranchial gill rakers further decreasing in size. Fins. Dorsal fin with 16���17 spines and with 9���10 rays. First dorsal-fin spine always shortest. Dorsal-fin base length between 50.2���55.6 % SL. Posterior end of dorsal-fin rays ending slightly before or at caudal fin base; posterior tip of anal fin ending slightly before caudal-fin base. Caudal-fin outline subtruncate and fin composed of 26���29 rays (16 principal caudal-fin rays and 10���13 procurrent caudal-fin rays). Anal fin with three spines (third spine longest) and 7���9 rays. Anal-fin base length between 15.2���20.1 % SL. Pectoral fin with 15���16 rays. Pectoralfin length between 21.6���25.7 % SL, longest pectoral ray not reaching level of anus. First upper and lower pectoralfin rays very short to short. Pelvic fin with first spine thickly covered with skin and five rays. Pelvic-fin base slightly posterior of pectoral-fin base. Pelvic fin slightly longer than pectoral fin; longest pelvic-fin ray almost reaching anus (ending approximately 0.5���2 flank scale widths before). ......continued on the next page Vertebrae and caudal fin skeleton. (Fig. 3). A total of 30 vertebrae (excluding urostyle element), with 14 abdominal and 16 caudal vertebrae. The pterygiophore supporting last dorsal-fin spine is inserted between neural spines of 16th and 17th vertebra (counted from anterior to posterior). Pterygiophore supporting last anal-fin spine is inserted between haemal spines of 15th and 16th vertebra, rarely between ribs of 14th and haemal spine of 15th vertebra (N=2). Single predorsal bone (=supraneural bone) present. Hypurals 1 and 2 as well as hypurals 3 and 4 always fused into single seamless units. Colouration in life (based on field photographs of adult specimens). (Fig. 3) Body ground colouration pale brown to light grey; anterior flank with yellow to golden reticulated pattern which becomes less prominent at level of anus and stops at level of caudal peduncle. Dark grey to brownish, interrupted midlateral band from operculum to just posterior caudal fin base, ending in mostly visible blotch; intensity midlateral band varies depending on mood often hardly visible. Midlateral band crossed by 13���15 vertical bars, which extend mainly ventrally, hardly recognizable except for more distinct first 4���5 anterior bars. In some specimens dorsum with irregular dark brown areas, which sometimes connect with midlateral band. Scales on, above and below midlateral band until level of anus with blackish-blue to greyish-blue centres. Dorsum and caudal peduncle pale brown to light grey; chest and belly light beige. Dorsal head surface pale brown to light grey; snout and cheek beige, ventrally brighter. Branchiostegal membrane light beige. Operculum beige to yellowish, sometimes with metallic turquoise speckles, a black opercular spot connecting with anterior extension of midlateral band (interrupted at level of preoperculum) ending in well-pigmented blotch slightly anterior of eye. Another dark grey to brownish element of variable form on ventral corner of operculum. Cheek with small, dark grey to brownish vertical stripe of variable shape and intensity, extending to slightly below eye (not reaching eye). Dark grey to brownish lachrymal stripe ending at posterior end upper lip. Very thin, dark grey to brownish nostril stripe (sometimes interrupted) V -shaped, extending between nostrils. Thin, dark grey to brownish interorbital stripe present; no distinct supraorbital stripe, but area just above eye somewhat darker than remaining dorsal head region. Upper and lower lip beige to pale brown, lower margin of upper lip greyish (darker coloured), lower lip lighter than upper. Dorsal-fin membrane transparent with orange maculae, sometimes arranged in inclined rows; maculae bordered with orange and outlined with black, especially in spinous part of fin. Anal fin transparent to yellow, towards margin becoming more intensively coloured, no maculae or eggspots present. Caudal fin yellowish to greyish with two or three rows of small yelloworange maculae near fin base. Outer caudal-fin rays with black margin. Pectoral and pelvic fins transparent but rays yellowish to greyish. Juvenile colouration in life. No information about juvenile colouration available. Colouration in alcohol. Colouration and melanin patterns similar to live specimens, but due the preservation procedure of specimens, i.e., first formalin fixation, transfer to 75 % EtOH etc., specimens tend to lose original colouration (especially melanin patterns more intense than in live specimens). Overall body ground colouration light brownish; dorsum darker than flank below midlateral band. Chest and belly beige to yellowish-beige. Branchiostegal membrane beige, along operculum and ventrally becoming reddish brown. Dorsal head surface and dorsum brownish, ethmoidal region greyish-brown. Upper lip beige to light greyish anteriorly, lower lip beige. Cheek beige to pale brownish; vertical stripe on cheek faint. Operculum beige to pale brown greyish and with opercular spot as described above (brownish element on operculum less clearly defined than in live specimens and covering almost entire operculum). Head mask brownish. Midlateral band and vertical bars brownish and more intense (especially posterior bars). Dorsal fin whitish to light greyish and margins outlined in black; maculae visible but less intense and greyish. Anal fin whitish to beige; margins blackish outlined. Caudal fin light whitish to beige; margins blackish outlined, small greyish speckles visible on membrane. Pectoral fin and pelvic fin whitish to light grey. Distribution and biology. Orthochromis mporokoso is known from two clear water streams in the vicinity of Mporokoso town. Kasinsha stream (holotype locality, Fig. 1) is about five meters wide with a rocky bottom and on average 50���100 cm deep (Fig. 8). The water temperature at the type locality was 19.5 ��C (15.07.2011, late afternoon) and had a pH of 6.7; at the second sampling locality (Mutoloshi River at Kapuma Falls) a temperature of 19.3 ��C (15.07.2011) and a pH of 7.3 was recorded (pers. comm. H. van Heusden 2017). Orthochromis mporokoso is a benthic-rheophilic species. Etymology. The species name mporokoso is derived from Mporokoso, a town in the Northern Province (Zambia) near the type locality of the species. A noun in apposition., Published as part of Schedel, Frederic Dieter Benedikt, Vreven, Emmanuel J. W. M. N., Manda, Bauchet Katemo, Abwe, Emmanuel, Manda, Auguste Chocha & Schliewen, Ulrich Kurt, 2018, Description of five new rheophilic Orthochromis species (Teleostei: Cichlidae) from the Upper Congo drainage in Zambia and the Democratic Republic of the Congo, pp. 301-349 in Zootaxa 4461 (3) on pages 308-313, DOI: 10.11646/zootaxa.4461.3.1, http://zenodo.org/record/1460091, {"references":["Schedel, F. D. B., Friel, J. P. & Schliewen, U. K. (2014) Haplochromis vanheusdeni, a new haplochromine cichlid species from the Great Ruaha River drainage, Rufiji basin, Tanzania (Teleostei, Perciformes, Cichlidae). Spixiana, 37 (1), 135 - 149."]}

Orthochromis kimpala sp. nov. Holotype. MRAC 2012-031 -P-2096 (84.58 mm SL), Democratic Republic of the Congo, Kalule Nord River, right tributary of Lualaba River, near to the bridge on road Makulakulu-Lubudi (-9.6935/25.8479). Paratypes. ZSM 46849 (2, ex MRAC uncat., 62.7���78.8 mm SL), collected with holotype.��� ZSM 46850 (1, ex MRAC uncat., 44.0 mm SL), collected with holotype.��� MRAC 2015-005 -P-0032-0033 (2, 56.9���62.6 mm SL), Democratic Republic of the Congo, Kalule Nord River, bridge Lubudi-Luena (-9.693472/25.847833). ��� MRAC 2015-005 -P-0034-0035 (2, 56.3���60.5 mm SL), Democratic Republic of Congo, Kalule Nord River, Kyabule village, bridge Mukulakulu-Kolwezi (-9.66725/25.740056). ��� MRAC 2015-005 -P-0036-0037 (2, 57.7���61.3 mm SL), Democratic Republic of the Congo, Kalule Nord River, Kyabule village, bridge Mukulakulu-Kolwezi (- 9.66725/25.740056). Differential diagnosis. Orthochromis kimpala can be readily distinguished from all species currently placed in Orthochromis (sensu de Vos & Seegers, 1998) except O. torrenticola, by presence of eggspot-like maculae on anal fin. Further, it is distinguished from Malagarasi- Orthochromis species, including O. sp. ���Igamba���, by having more scale rows on cheek (3���4 vs. 0 or 0���1 in case of O. mazimeroensis and O. rubrolabialis). Furthermore, O. kimpala differs from O. luichensis, O. malagaraziensis, O. mazimeroensis, O. mosoensis, and O. rubrolabialis by having more scales between upper lateral line and dorsal-fin origin (6���7 vs. 4���5). Additionally, it has fewer dorsalfin spines than O. luichensis, O. malagaraziensis , and O. rubrolabialis (15���16 vs. 17���19). Moreover, it differs from O. rubrolabialis by having more total gill rakers (11���12 vs. 8���9) and by position of pterygiophore supporting last dorsal-fin spine (vertebral count: 14-16 vs. 17-19); from O. mazimeroensis by having more abdominal vertebrae (14���15 vs. 12���13); from O. mosoensis by having more scales (horizontal line) on operculum (3 vs. 0���1). O. kimpala is distinguished from O. kasuluensis, O. rugufuensis and O. uvinzae by having fewer dorsal-fin spines (15���16 vs. 17-20); from O. kasuluensis and O. rugufuensis by having more scales (horizontal line) on operculum (3 vs. 1���2); from O. kasuluensis and O. uvinzae by having fewer scales in upper lateral line (20���22 vs. 23���25) and fewer total vertebrae (28���30 vs. 31���33). Moreover,it differs from O. uvinzae by having fewer horizontal line scales (27���29 vs. 30���32) and by position of pterygiophore supporting last dorsal-fin spine (vertebral count: 14���16 vs. 18��� 19). It can be distinguished from O. kalungwishiensis, O. luongoensis, O. polyacanthus, and O. torrenticola by having fewer dorsal-fin spines (15���16 vs. 17���20); further from O. kalungwishiensis, O. luongoensis, and O. torrenticola by fewer horizontal line scales (27���29 vs. 30���32) and fewer total vertebrae (28���30 vs. 31���33); from O. luongoensis and O. torrenticola by fewer caudal vertebrae (13���16 vs. 17���18); from O. torrenticola by having fewer anal-fin spines (3 vs. 4). Moreover, it is distinguished from O. torrenticola and O. polyacanthus by position of pterygiophore supporting last anal-fin spine (vertebral count: 14���15 vs. 16���17). It is distinguished from O. stormsi by having fewer total gill rakers (11���12 vs. 13���15). It differs from S. neodon by having more scale rows on cheek (3���4 vs. 1���2), fewer horizontal line scales (27���29 vs. 30���31), more circumpeduncular scales (16 vs. 12), fewer inner series of teeth (2���3 vs. 4���6). It differs from H. snoeksi by having fewer horizontal line scales (27���29 vs. 30��� 31), fewer scales on upper lateral line (20���22 vs. 23), more abdominal vertebrae (14���15 vs. 13) and fewer caudal vertebrae (13���16 vs. 17), more anal-fin rays (8���10 vs. 5���6) and more total gill rakers (11���12 vs. 9); from H. bakongo by having more scales between upper lateral line and dorsal-fin origin (6���7 vs. 3���5); from H. moeruensis by having more upper procurrent caudal-fin rays (6���7 vs. 5) and more total caudal-fin rays (26���27 vs. 28���29); from H. vanheusdeni by having more scale rows on cheek (3���4 vs. 0���2). It is distinguished from herein newly described species O. mporokoso by more scales between upper lateral line and dorsal-fin origin (6���7 vs. 4���5); from O. katumbii by having fewer horizontal line scales (27���29 vs. 30���31), and by more scales between upper lateral line and dorsal-fin origin (6���7 vs. 4���5); from O. gecki by having more series of scales on cheek (3���4 vs. 0���2); from O. indermauri by having more series of scales on cheek (3���4 vs. 1���2) and by fewer dorsal-fin spines (15���16 vs. 17��� 18). Description. Morphometric measurements and meristic characters are based on 10 type specimens. Values and their ranges are presented in Table 4. For general appearance see figure 5. Maximum length of wild caught specimens 84.6 mm SL. Moderately slender species with maximum body depth (24.8���30.5 % SL) at level of first dorsal-fin spine, decreasing rather quickly towards caudal peduncle. Caudal peduncle rather short and deep (ratio of caudal peduncle length to depth: 1.2���1.4). Head length almost one third of standard length. Dorsal-head profile rather strongly curved and without a prominent nuchal gibbosity. Eye diameter larger than interorbital width. Jaws isognathous. Posterior tip of maxilla reaching or almost reaching to anterior margin of orbit. Lips not noticeably enlarged or thickened, but upper lip becoming thicker posteriorly. Two separate lateral lines. Squamation. Flank above and below lateral lines covered with comparatively large, well developed ctenoid scales. Anterior dorsal and ventral flank covered by cycloid scales. Margin of belly with deeply embedded medium sized scales; central belly region scaleless. Chest covered with minute, deeply embedded cycloid scales, giving impression of a scaleless chest; chest to flank transition with larger cycloid scales, however, still deeply embedded. Snout scaleless. Interorbital scales minute to small, cycloid and deeply embedded. Nape region covered with small, deeply embedded cycloid scales becoming slightly larger towards occipital region. Occipital region with small to medium sized cycloid scales. Cheek covered by medium sized cycloid scales; 3���4 scale rows on cheek. Cycloid scales on operculum of medium size and variable shape (ovoid to circular); opercular blotch only on anterior margins covered by medium sized scales, main area of opercular blotch scaleless. Three scales on a horizontal line starting from edge of postero-dorsal angle of operculum to anterior edge of operculum. ......continued on the next Upper lateral line scales 20���22 and lower lateral line 8���11. Horizontal line scales 27���29. Caudal fin with 0���2 pored scales. Upper and lower lateral lines separated by two scales; 6���7 scales between upper lateral line and dorsal-fin origin. Anterior part of caudal fin covered with 2���3 vertical rows of small cycloid scales; with median scales slightly larger; scaled area of caudal fin extended posteriorly especially at upper and lower area with minute, interradial scales (approximately up to one half of caudal fin). Sixteen scales around caudal peduncle. Jaws and dentition. Anterior teeth of outer row of upper and lower jaw bicuspid to subequal bicuspid, large and moderately closely set; towards corner of mouth, teeth smaller and more widely set and unicuspid. Individual bicuspid teeth with minimally expanded brownish crown, cusps uncompressed and moderately narrowly set, neck moderately stout. Outer row of upper jaw with 30���47 teeth and outer row of lower jaw with 28���38 teeth (specimens: 44.4���84.6 mm SL); larger specimens generally with more teeth. Two to three inner upper and lower jaw tooth rows with small tricuspid teeth (rarely bicuspid). Lower pharyngeal bone (Fig. 5) of single dissected paratype (ZSM 46849, 62.7 mm SL) about 1.2 times wider than long with anterior keel about 0.5 times of length of dentigerous area. Dentigerous area of lower pharyngeal bone about 1.6 times wider than long, with 11+11 (empty tooth-sockets included) teeth along posterior margin and eight teeth along midline. Anterior pharyngeal teeth (towards keel) bevelled to pronounced and slender; those of posterior row larger than anterior ones, bevelled (minor cusp not well developed). Largest teeth medially situated in posterior tooth row. Teeth along midline slightly larger than more lateral ones. Gill rakers. Total gill raker count 11, with 2���3 epibranchial, one in angle, and 7���8 ceratobranchial gill rakers. Most anterior ceratobranchial gill rakers smallest increasing quickly in size towards cartilaginous plug (angle). Gill raker in angle slightly shorter than longest ceratobranchial gill raker and epibranchial gill rakers further decreasing in size. Fins. Dorsal fin with 15���16 spines and with 10���11 rays. First dorsal-fin spine always shortest. Dorsal-fin base length between 51.4���56.9 % SL. Posterior end of dorsal-fin rays reaching or slightly extending beyond caudal fin base; posterior tip of anal fin ending slightly before caudal fin base. Caudal fin outline subtruncate and fin composed of 28���29 rays (16 principal caudal-fin rays and 12���13 procurrent caudal-fin rays). Anal fin with 3 spines (3rd spine longest) and 8���10 rays. Anal-fin base length between 17.4���20.6 % SL. Pectoral fin with 14���16 rays. Pectoral-fin length between 20.6���24.8 % SL; longest pectoral ray not reaching level of anus. First upper and lower pectoral-fin rays very short to short. Pelvic fin with 1 st spine thickly covered with skin and five rays. Pelvic-fin base slightly more posterior than pectoral fin base. Longest pelvic-fin ray not reaching anus (ending approximately 3 flank scale widths before). Vertebrae and caudal fin skeleton. 28���30 total vertebrae (excluding urostyle element), with 14���15 abdominal and 13���16 caudal vertebrae. Pterygiophore supporting last dorsal-fin spine inserted between neural spines of 14th and 15th, 15th and 16th or 17th and 18th vertebra (counted from anterior to posterior). Pterygiophore supporting last anal-fin spine is inserted between rips of 14th (or 15th) and haemal spine of 15th (or 16th) vertebra or between haemal spine of 15th and 16th vertebra. Single predorsal bone (=supraneural bone) present. Hypurals 1 and 2 as well as hypurals 3 and 4 clearly separated (most common state) or fused while any other combination is possible (e.g. hypurals 1 and 2 fused and hypurals 3 and 4 separated or vice versa). Colouration in life (based on field photographs of adult specimens). Body ground colouration pale brown to beige; dorsum, flank and caudal peduncle light brown; belly whitish; chest whitish to yellow. Dark grey to blackish, interrupted midlateral band from operculum to just behind caudal fin base, ending in dark blotch; midlateral band crossed by 7���9 light grey vertical bars (sometimes hardly visible) extending mainly dorsally; at level of upper lateral line most bars fuse forming dorso-lateral band which extends to posterior origin dorsal fin. Scales on flank and dorsum with orange blotch on anterior surface and greenish metallic highlights, especially scales on or row above or below lower lateral line. Dorsal head surface brownish; anterior snout brownish, preorbital area and cheek yellowish to brownish; mental area and ventral parts of preoperculum and cheek light bluish. Operculum yellowish with brownish sprinkles; black opercular spot present. Greyish vertical preopercular stripe of variable intensity is always present, at least in the form of a faint blackish blotch at mid orbit level. Dark grey to brownish lachrymal stripe between orbit and posterior end upper lip. Greyish to brownish nostril stripe (less intense than lachrymal stripe) fused posteriorly with lachrymal stripe. Faint greyish interorbital stripe. Upper lip brownish to olive, beige to light bluish posteriorly and lower lip beige to light bluish. Dorsal fin membrane greyish with orange margins; soft rayed part of dorsal fin with orange maculae arranged in 2���3 rows. Anal-fin membrane greyish, margin of spinous part dark grey; 2���3 orange maculae on soft rayed part anal fin. First macula situated just posterior last anal-fin spine at outer margin of anal fin. Second macula almost in centre of rayed part anal fin. When present, third macula less prominent (smaller and less colourful). Maculae resembling eggspots but without white concentric ring. Caudal fin yellowish with grey margin and four columns of small orange maculae. Pectoral fin yellowish. Pelvic fin yellowish; skin around pelvic fin spine and adjacent membrane of first two rays blackish. Juvenile colouration in live. No information about juvenile colouration available. Colouration in alcohol. Colouration and melanin patterns similar to live specimens, but due the preservation procedure of specimens, i.e., first formalin fixation, transfer to 75 % EtOH etc., specimens tend to lose original colouration (especially melanin patterns more intense than in live specimens). Overall body ground colouration brownish; dorsum and flank brownish. Orange blotches on flank scales no longer visible. Chest and belly beige to light brown. Branchiostegal membrane greyish brown. Dorsal head surface brownish, ethmoidal region greyish brown. Upper lip greyish; lower lip greyish anteriorly becoming beige. Cheek light brown to brownish. Preoperculum greyish. Operculum dark brown to greyish with opercular spot as described above. Head mask dark brownish to grey. Midlateral band, vertical bars and dorso-lateral band brownish. Dorsal fin greyish, lappets with very fine black seam; maculae on soft-rayed part beige. Anal fin greyish; margin dark grey to black, eggspot-like maculae whitish. Caudal fin greyish with dark greyish margin; maculae dark grey. Pectoral fin light grey. Pelvic fin light grey, skin around pelvic fin spine and adjacent membrane of first two rays dark grey. Distribution and biology. Orthochromis kimpala is known from the Kalule Nord River (Fig. 1), a right tributary of the Lualaba River in the Democratic Republic of the Congo. At the type locality the Kalule Nord River has a rocky bottom with some patches of sand and gravel, and is about 5���8 meters wide and on average about 50 cm deep (Fig. 8). Water temperature varied between 21.1 and 26.8 ��C (measured over several years in August and September), pH between 7.95���8.71, electrical conductivity 333.5���359 ��S. The species appears to be benthicrheophilic. Etymology. The species name kimpala refers to the local name for this species: ���Kimpala��� in the Sanga language. A noun in apposition., Published as part of Schedel, Frederic Dieter Benedikt, Vreven, Emmanuel J. W. M. N., Manda, Bauchet Katemo, Abwe, Emmanuel, Manda, Auguste Chocha & Schliewen, Ulrich Kurt, 2018, Description of five new rheophilic Orthochromis species (Teleostei: Cichlidae) from the Upper Congo drainage in Zambia and the Democratic Republic of the Congo, pp. 301-349 in Zootaxa 4461 (3) on pages 318-323, DOI: 10.11646/zootaxa.4461.3.1, http://zenodo.org/record/1460091, {"references":["De Vos, L. & Seegers, L. (1998) Seven new Orthochromis species (Teleostei: Cichlidae) from the Malagarasi, Luiche and Rugufu basins (Lake Tanganyika drainage), with notes on their reproductive biology. Ichthyological Exploration of Freshwaters, 9 (4), 371 - 420."]}

Orthochromis gecki sp. nov. Orthochromis sp. “Lubudi” Holotype. MRAC 2012-031 -P-2097 (73.8 mm SL), Democratic Republic of Congo, Lubudi River downstream of Kendo Rapids, near Tshifuntshi Village (-10.5635/24.6354). Paratype. MRAC 2012-031 -P- 2098-2116 (19, 52.1–77.7 mm SL), collected with holotype.— ZSM 46851 (5, ex MRAC uncat., 46.3–62.9 mm SL), Democratic Republic of Congo, Lubudi River at Kendo Rapids, near Tshifuntshi Village (-10.5668/24.6373). — MRAC 2012-031 -P- 2117-2126 (10, 45.9–69.8 mm SL), Democratic Republic of Congo, Lubudi River at Kendo Rapids, near Tshifuntshi Village (-10.5670/24.6374). – ZSM 46852 (1, ex MRAC uncat., 67.1 mm SL), collected with holotype. Differential diagnosis. Orthochromis gecki can be readily distinguished from all all species currently placed in Orthochromis (sensu de Vos & Seegers 1998) except O. torrenticola (which has eggspot-like maculae) by presence of eggspots on anal fin. It is further distinguished from O. kasuluensis by having fewer anal-fin rays (8–9 vs. 10); from O. malagaraziensis by having more scales between upper lateral line and dorsal-fin origin (5–8 vs. 3– 4); from O. mazimeroensis by having more horizontal line scales (29–31 vs. 26–28); from O. rubrolabialis, O. rugufuensis and O. uvinzae by having fewer anal-fin spines (16–17 vs. 18–20) and in position of pterygiophore supporting last dorsal-fin spine (vertebral count: 15–16 vs. 17–19). It is furthermore distinguished from O. uvinzae by having fewer abdominal vertebrae (13–14 vs. 15–16) and by position of pterygiophore supporting last anal-fin spine (vertebral count: 14–15 vs. 16–17). O. gecki is distinguished from O. stormsi by having more horizontal line scales (29–31 vs. 26–28) and fewer total gill rakers (9–12 vs. 13–15); from O. polyacanthus by having fewer dorsal-fin spines (16–17 vs. 18–20), more dorsal-fin rays (10–12 vs. 8–9) and it is distinguished by position of pterygiophore supporting last dorsal-fin spine (vertebral count: 15–16 vs. 17–18); from O. torrenticola by having fewer anal-fin spines (3 vs. 4). Meristic values of O. gecki overlap with those of O. luongoensis, O. kalungwishiensis , and O. machadoi but is distinguished by narrower interorbital width (9.62–12.86 vs. 13.18-21.27 % HL). It is distinguished from S. neodon by having more circumpeduncular scales (16 vs. 12); from H. snoeksi by having more anal-fin rays (8–9 vs. 5–6); from H. bakongo by more horizontal line scales (29–31 vs. 26–28), more dorsal-fin spines (16–17 vs. 15–15) and by position of pterygiophore supporting last dorsal-fin spine (vertebral count: 15–16 vs. 13–14); from H. moeruensis by having more horizontal line scales (29–31 vs. 27–28) and more scales in upper lateral line (21–25 vs. 19–20). Meristic values of O. gecki overlap with those of H. vanheusdeni but is distinguished by having a smaller interorbital width (9.62–12.86 vs. 14.20–20.30 % HL). It is distinguished from herein newly described species O. kimpala by having fewer series of scales on cheek (0–2 vs. 3–4). Meristic values of O. gecki overlap with those of O. mporokoso, O. katumbii, and O. indermauri but is distinguished by having smaller interorbital width (9.6–12.9 vs. 13.0–21.7 % HL). Description. Morphometric measurements and meristic characters are based on 36 type specimens. Values and their ranges are presented in Table 5. For general appearance see figure 6. Maximum length of wild caught specimens 77.7 mm SL. Rather slender and elongated species with maximum body depth (20.2–27.4 % SL) slightly before or at level of first dorsal-fin spine, decreasing rather gradually towards caudal peduncle. Caudal peduncle moderately elongated and deep (ratio of caudal peduncle length to depth: 1.5–2.0). Head length about one third of standard length. Dorsal-head profile moderately curved, from anterior eye region to dorsal-fin origin only slightly curved. No prominent nuchal gibbosity present. Eye diameter larger than interorbital width. Jaws isognathous. Posterior tip of maxilla almost reaching to slightly beyond anterior orbit margin. Lips well developed. Two separate lateral lines. Squamation. Flank above and below lateral lines covered with comparatively large ctenoid scales. Anterior dorsal and ventral flank covered by cycloid scales. Margin of belly with deeply embedded minute to small sized scales; central belly region scaleless. Chest completely scaleless, except for deeply embedded cycloid scales ventro-anteriorly of pectoral fin. Chest to flank transition relatively abrupt with small, embedded cycloid scales. Snout scaleless. Interorbital region scaleless or with minute, deeply embedded cycloid scales. Nape region covered with minute to small, embedded cycloid scales becoming slightly larger towards occipital region. Occipital region with small to medium sized cycloid scales. Cheek covered with small, partly deeply embedded cycloid scales sometimes almost appearing scaleless; 0-2 scale rows on cheek. Cycloid scales on operculum of variable size (small to medium) and variable shape (ovoid to circular); opercular blotch only on anterior margin covered with medium sized scales, main area of opercular blotch scaleless. 1–3 scales in column from edge of postero-dorsal angle of operculum to anterior edge of operculum. Upper lateral line scales 21–25 and lower lateral line 8–12. Horizontal line scales 29–31. Caudal fin with 0–1 pored scale. Upper and lower lateral lines separated by two scales. 5–8 scales between upper lateral line and dorsalfin origin. Anterior part of caudal fin covered with 2–3 columns of small cycloid scales; with median scales being slightly larger; scaled area of caudal fin extended posteriorly, especially at upper and lower end, with minute, interradial scales (approximately up to one half of caudal fin). Sixteen scales around caudal peduncle. Jaws and dentition. Anterior teeth of outer row of upper and lower jaw bicuspid to subequally bicuspid, large and closely set; towards corner of mouth, teeth smaller and more widely set and becoming unicuspid (rarely tricuspid or subequally bicuspid teeth present in posterior upper jaw). Individual bicuspid teeth without or minimally expanded brownish crown, cusps (tips roundish) uncompressed and moderately narrowly set, neck moderately stout. Outer row of upper jaw with 33–49 teeth and outer row of lower jaw with 26–42 teeth (specimens: 46.3–77.7 mm SL); larger specimens generally with more teeth. Upper and lower jaw with 2–4 inner tooth rows with small tricuspid teeth (rarely 5 rows in upper jaw and 1 or 5 in lower jaw); larger specimens generally with more inner tooth rows. Lower pharyngeal bone (Fig. 6) of single dissected paratype (MRAC 2012- 031-P- 2098-2116, 69.1 mm SL) about 1.1 times wider than long with anterior keel about 0.6 times length of dentigerous area. Dentigerous area of lower pharyngeal bone about 1.4 times wider than long, with 10+9 teeth along posterior margin and 6 teeth along midline. Anterior pharyngeal teeth (towards keel) bevelled to pronounced and slender; those of posterior row larger than anterior ones, bevelled (minor cusp not well developed). Largest teeth medially in posterior tooth row. Teeth along midline slightly larger than more lateral ones. Gill rakers. Total gill raker count 9–12, with 1–2 epibranchial, one angle, and 7–9 ceratobranchial gill rakers. Anteriormost ceratobranchial gill rakers smallest, increasing in size towards cartilaginous plug (angle). Anterior gill rakers on ceratobranchial unifid, towards cartilaginous plug sometimes bifid or trifid. Raker on cartilaginous plug largest in size and in most cases trifid, sometimes bifid. Epibranchial gill rakers then decreasing in size. Fins. Dorsal fin with 16–17 spines and with 10–12 rays. First dorsal-fin spine always shortest. Dorsal-fin base length between 52.1–61.0 % SL. Posterior tip of dorsal-fin rays reaching slightly beyond caudal fin base; posterior tip of anal fin reaching slightly before or at caudal-fin base. Caudal fin outline subtruncate and composed of 27–29 rays (16 principal caudal-fin rays and 11–13 procurrent caudal-fin rays). Anal fin with 3 spines (3rd spine longest) and 8–9 rays. Anal-fin base length between 15.6–20.7 % SL. Pectoral fin with 15–16 rays. Pectoral-fin length between 19.6–25.0 % SL; longest pectoral ray not reaching level of anus; first upper and lower pectoral-fin rays very short to short. Pelvic fin with 1 st spine thickly covered with skin and 5 rays. Pelvic-fin base at level or slightly anterior of pectoral-fin base. Pelvic fin ending at same level as pectoral fin; longest pelvic-fin ray not reaching anus (ending approximately 2-3 flank scale widths before). Vertebrae and caudal fin skeleton. 29–31 total vertebrae (excluding urostyle element), with 13–14 abdominal and 16–18 caudal vertebrae. Pterygiophore supporting last dorsal-fin spine inserted between neural spines of 15th and 16th or 16th and 17th vertebra (counted from anterior to posterior). Pterygiophore supporting last anal-fin spine is inserted between haemal spines of 15th and 16th vertebra or between rips of 14th and haemal spine of 15th vertebra. Single predorsal bone (=supraneural) present. Hypurals 1 and 2 in most types fused into either single, seamless unit or separated by clearly distinct seam. Hypurals 3 and 4 always fused into single seamless unit, except for one paratype which has clearly separated hypurals. ......continued on the next page Colouration in life (based on field photographs of adult specimens). Body ground colouration brownish to greyish; dorsum, flanks and caudal peduncle greyish, beneath lower lateral line becoming yellowish; belly yellow; chest anteriorly whitish and remaining area yellow. Dark grey interrupted midlateral band from eye (anteriorly extended midlateral band) to just behind caudal-fin base ending in well pigmented vertically elongated blotch. Midlateral band crossed by 7–9 greyish vertical bars; at level of upper lateral line they sometimes fuse with each other forming dorso-lateral band sometimes interrupted and ending at posterior end of dorsal fin. On ventral flank at level of pectoral fin vertical bars sometimes fuse to ventro-lateral band (less intensive then previous mentioned ones) that ends well before level of anus. Iris dorsally yellow remaining greyish. Dorsal head surface, ethmoidal area, preorbital area greyish; cheek greyish near eyes, yellowish below and with vertical stripe-like pattern centrally (less distinct than other stripes of face mask). Preoperculum light greyish-yellow; operculum greyish, black opercular spot outlined with yellow. Branchiostegal membrane brownish to orange. Dark grey lachrymal stripe ending slightly anterior of caudal end upper lip. Greyish nostril stripe caudally fused with lachrymal stripe (beneath eye); interorbital stripe greyish. No clearly defined supraorbital stripe or nape band but recognizable to some extent by darker (grey) colouration than remaining dorsal head surface. Upper lip and lower lip yelloworange; upper and lower margin of upper lip greyish. Dorsal-fin membrane brownish (especially spinous part) to yellowish (soft rayed part); margin orange; brownish to dark greyish maculae from about posterior half of spiny part to end soft-rayed part arranged in several almost vertical columns. Anal-fin membrane transparent proximally becoming yellowish distally (soft rayed part), margin of spiny and soft-rayed part black becoming yellow to brownish towards posterior tip; 3–6 orange eggspots (large orange centre surrounded by yellow concentring ring and outlined by more or less ill-defined transparent margin) on anal fin in both sexes. Eggspots arranged into 1–2 rows, first eggspot located centrally on fin just behind last anal spine. Caudal fin yellowish, orangey distally, margin outlined in grey-black; caudal with brownish maculae arranged into 3–4 vertical columns. Pectoral fin transparent, rays greyish. Pelvic fin deep black (especially skin around spine) except for small yellow central portion of rayed area. Juvenile colouration in live. (based on wild caught juveniles of approximately 25 mm SL; Fig. 9). Ground colouration beige, belly whitish. Patterns and head mask as described for adults but less prominent. Brown to greyish vertical bars on flank appear wider than in adults, dorso-lateral band and ventro-lateral band not visible. Last vertical bar on caudal fin base roundish blotch extending onto caudal fin (not a vertical bar as in adults). Dorsal fin brownish with several hyaline patches, margin not orange. Anal fin light brownish-orange; no eggspots on anal fin present. Caudal fin brownish-orange, no maculae present. Pectoral fin hyaline. Pelvic fin white to yellowish. Colouration in alcohol. Colouration and melanin patterns similar to live specimens, due the preservation procedure of specimens, i.e., first formalin fixation, transfer to 75 % EtOH etc., specimens tend to lose original colouration (especially melanin patterns more intense than in live specimens). Overall body ground colouration brownish; dorsum and flank brownish becoming brighter ventrally. Chest and belly light brown to beige. Branchiostegal membrane dark greyish. Dorsal head surface brownish; ethmoidal area greyish brown. Upper and lower lip beige; upper and lower margin of upper lip greyish brown. Cheek light brown to brownish; cheek stripe dark brown. Operculum dark brown becoming somewhat darker ventrally; with opercular spot as described above. Head mask dark grey. Midlateral band, vertical bars, dorso-lateral band and ventro-lateral band dark brown. Dorsal fin greyish brown becoming greyish beige caudally, margin blackish with very fine black seam; maculae on spiny and soft-rayed part dark grey. Anal fin beige with blackish distal margin and dark grey at posterior margin; eggspots on anal fin faded and not visible in preserved specimens. Caudal fin beige to light greyish with dark greyish margin; maculae dark grey. Pectoral fin beige to light grey. Pelvic fin deep black except small central portion of rayed part greyish. Distribution and biology. Orthochromis gecki is known from the Lubudi River a left-hand tributary of the Lualaba River in the Katanga region, Democratic Republic of the Congo (Fig. 1). It was also found to be present in the Mukuleshi River. At the type locality the Lubudi River has a rocky bottom with patches of gravel and sand, and is about 15 meters wide and about 50 cm deep; upstream the river is much deeper with 3 meters or more (Fig. 9). O. gecki seems to be a maternal mouthbrooder. One of the female paratypes (MRAC 2012-031-P- 2117-2126; 57.0 mm SL), was found mouthbrooding when preserved and carried around 12 comparatively large eggs. Fixed eggs are brownish and oval and ca. 3.8 mm long and 2.5 mm wide. Etymology. The species is named in honour of Mr. Jakob Geck who is a passionate, German fish naturalist, thanking him for his dedicated volunteer work and untiring support for the ichthyology section of the ZSM. His great experience in keeping rheophilic cichlids contributed to the knowledge of behaviour and ecology of many cichlid taxa, including O. katumbii and O. indermauri.