Garra jamila, Moritz & Straube & Neumann, 2019

Moritz, Timo, Straube, Nicolas & Neumann, Dirk, 2019, The Garra species (Cyprinidae) of the Main Nile basin with description of three new species, Cybium 43 (4), pp. 311-329 : 319-322

Garra jamila , new species

( Figs 11-13 , Tabs IV-V)

Material

Holotype. – ZSM 47245 (ex ZSM 46926 #3), 54.2 mm SL, Sudan: Atbara River , artificial stream fed by overflow of irrigation canal near hydroelectric turbine house of Khashm el Girba dam (N14.93° E35.91°), coll. D. Neumann, T. Moritz & J. Fischer, 29 Mar. 2018.

Paratypes. – ZSM 46925 (6 now 2), 34.4-47.6 mm SL, same data as holotype ; AMNH 264146 (2) (ex ZSM 46925 ), 36.0- 37.4 mm SL, same data as holotype ; BMNH 2018.9.3.3-4 (2) (ex ZSM 46925 ), 36.1-42.6 mm SL, same data as holotype ; ZSM 46926 (9 now 6), 30.9-62.7 mm SL, same data as holotype ; DMM IE/15074 (2) (ex ZSM 46926 ), 50.6-52.9 mm SL, same data as holotype .

Diagnosis

Garra jamila differs from all other African Garra species, except G. napata and G. ethelwynnae , in an asquamate area along the dorsum which exceeds well beyond the dorsal fin insertion ( Fig. 6C ) and laterally onto flanks and thus accounting for an incomplete scale row count of only 2 to 2.5 scales (vs. 3 or more) between dorsal fin insertion and the lateral line. It is distinguished from G. ethelwynnae from the Damas River basin ( Eritrea) by an asquamate postpelvic area (vs. squamate) and more scales in lateral line (34- 38 vs. 32-34). Garra jamila is distinguished from G. napata from the Main Nile basin by its well-developed disc [type C] with prominent free posterior flap (vs. intermediate [type B] with very small or absent posterior flap), crenate upper lip (vs. smooth); by its vivid red colouration of the distal end of the anal fin when alive (vs. anal fin lacking any red col- ours); a small dark humeral spot usually as large or smaller than the red postopercular spot (vs. humeral spot twice as large as postopercular spot); fixed specimens with very dark blackish to brown colouration on back and contrasting light belly (vs. entire body grey beige). It is distinguished from G. vinciguerrae by a naked predorsal area that exceeds laterally beyond dorsal fin (vs. at least single, irregular predorsal scales present on nape); middle of dorsal fin membrane with prominent dark horizontal band (vs. no such band); from G. sannarensis by its well-developed disc [type C] (vs. intermediate type B disc); posterior disc flap rounded and of equal width (vs. caudally slightly extended, oval shaped flap with bulky middle); from G. sp. “White Nile” in having prominent stout short barbels, not reaching onto lower lip pad when flexed inwards (vs. barbels nearly touching each other when flexed inwards).

Description

Based on holotype ( Fig. 11 ) and 14 paratypes. The largest specimen ( Fig. 12 , ZSM 46926: SUD-2018/1041) differs from the rest of type series in some phenotypic aspects and is referred to as “the large specimen” if deviating. Maximal recorded size 62.7 mm SL (78.3 mm TL). Counts and proportional measurements in tables IV and V. Laterally compressed and rather deep-bodied Garra , species with moderately or clearly flattened (large specimen) head profile. Disc well developed (type C) and oval shaped (shorter as broad), lateroposterior flap distinct and either well-developed, papillate and nearly as broad as disc ( Fig. 5D ) or disc smooth and more than twice as long as flap and laterally reduced (large specimen, Fig. 5E ); central callus of disc as wide as mouth. Rostral cap not as prominent as in G. vinciguerrae but in comparison to all other Main Nile species well developed and distinct, margin fringed, maxillary barbels well-developed but stout and rather short or very short (large specimen). Dorsal fin origin at centre of body, posterior margin straight to slightly convex; usually 3-4 unbranched rays, one or two minute rays deeply embedded into the anterior fin tissue and recognisable only on X-ray images, followed by one smaller and one larger simple ray and 7 branched rays. Pectoral fins inserting low on body; pelvic fins nearly reaching anal fin insertion. Posterior margin of anal fin convex, three small simple rays, the first deeply embedded into anterior fin tissue and visible only via X-ray imaging, followed by 5 branched rays. Caudal fin emarginated, upper and lower lobes rounded. Scales on body flanks large; chest, belly and postpelvic area scaleless; area in front and around dorsal fin base asquamate, laterally expanding ( Fig. 6C ) on body flanks and thus reducing scale row count to only 2-2.5 com- plete scale rows between dorsal fin insertion and lateral line.

Colouration. – In life very colourful Garra species with pinkish or golden body directly after capture, in large specimen red; head, cheek, flanks scales and back dark green to olive scales and strongly pigmented; pigmented areas on flank scales often confined to anterior scale centres near scale pocket membranes; number of lighter scales with unpigmented posterior margin increasing towards belly ( Fig. 13 ). Iris bright orange or red. Spot on posterior dorsal corner of opercle deeply red and of same size as in directly bordering dark-green ‘humeral’ spot on first lateral line scale. Pectoral, pelvic and anal fins yellowish, anal fin anteriorly red, unbranched rays of pectoral and pelvic fin with distinct white margin. Caudal peduncle with distinct dark, slightly rectangular bar. Caudal fin membrane vividly yellow, dark grey melanophores along rays and increasing in number towards proximal part in subadults, in adults forming conspicuous horizontal stripes in the fin centre; upper lobe and ventral half of lower lobe of caudal fin and lower margin of anal fin tinted intensively red. Centre of dorsal membrane at base of branched rays 2 or 3 to 6 with four to five prominent conflu- ent dark spots; towards middle of fin with conspicuous and broad dark grey or black band ( Fig. 7C ); anterior distal fin margin at unbranched and first three branched membranes red, towards its free distal end hyaline.

In preserved specimens, greenish body colouration turns into dark brown ( Figs 11-12 ); belly pale with marked border to dark lateral and dorsal body flanks; pigmentation differ- ences between anterior and posterior scale parts reversed or not traceable. First scale of lateral line behind opercle with dark blotch, dark vertical bar at the end of caudal peduncle visible. Pectoral, pelvic and anal fins pale opaque white; dark markings in dorsal fin visible in preserved specimens.

Distribution

Known so far only from the type locality: only in upper stretch of a small artificial stream fed by a pipe connecting to the headworks of the irrigation canal branching immediately at the Khashm el Girba dam on the Atbara River ( Figs 1 , 14 ) .

Figures

Figure 1. – Records of Garra species from the Main Nile basin (dotted line). Star – Garra vinciguerrae; diamond – G. napata; square – G. jamila; triangle – G. sannarensis; cross – G. sp. “White Nile”; numbers indicate the cataracts of the Nile river.

Figure 5. – Underside of head show- ing the different types of sucking-discs. A: Garra vinciguerrae; B: G. napa- ta; C: G. sannarensis; D: G. jamila, holotype; E: G. jamila, large speci- men; F: G. sp. “White Nile”. Scale bars = 5 mm.

Figure 6. – Scaled (dark) and unscaled (light grey) areas in dorsal view. A: Garra vinciguerrae; B: G. napata; C: G. jamila; D: G. sannarensis.

Figure 7. – Dorsal fin melanophore pattern. A: Garra vinciguerrae; B: G. napata; C: G. jamila; D: G. sannarensis.

Figure 11. – Garra jamila sp. nov., holotype, ZSM 47245 (ex ZSM 46926#3), 54.2 mm SL, Sudan:Atbara: Khashm el Girba, 29 Mar. 2018. Scale bar = 10 mm.

Figure 12. – Garra jamila sp. nov., large specimen, ZSM 46926#6, 62.7 mm SL, Sudan:Atbara: Khashm el Girba, 29 Mar. 2018. Scale bar = 10 mm.

Figure 13. – Live specimens of Garra jamila sp. nov. All from Khashm el Girba, Atbara, Sudan, 29 Mar 2018.A: ~ 35 mm SL; B: ~50 mm SL; C: 62.7 mm SL (ZSM 46926#6).

Figure 14. – Small artificial stream below Khashm el Girba dam (29 Mar. 2018). A: Type locality of G. jamila viewed downstream; B: Type locality viewed upstream.