Neobola kinondo Bart, Schmidt, Nyingi & Gathua, 2019
Tana sardine

Family:  Danionidae (Danios), subfamily: Chedrinae
Max. size:  6.48 cm SL (male/unsexed)
Environment:  benthopelagic; freshwater
Distribution:  Africa: Tana River in Kenya (Ref. 121710).
Diagnosis:  Dorsal spines (total): 0-0; Dorsal soft rays (total): 7-9; Anal spines: 0-0; Anal soft rays: 18-23. Diagnosis: Neobola kinondo is readily diagnosed from its presumed closest relative, N. fluviatilis, by higher counts of lateral line scales, 38-47 vs. 37-41; predorsal scales, 20-27 vs. 19-20; and caudal peduncle circumferential scales, 12-16 vs. 10-13; and lower counts of transverse scales, 7-11 vs. 8-10; principal dorsal-fin rays, 7-9 vs. 8-9; and principal anal-fin rays, 18-23 vs. 20-24 (Ref. 121710). Combining lateral line scales and pre-dorsal scales completely separates Neobola kinondo from N. fluviatilis; Neobola kinondo has a combined count of 61 or more scales and N. fluviatilis has fewer than 61 lateral line and predorsal scales (Ref. 121710). Neobola kinondo differs from N. bottegi by its higher numbers of lateral line scales, 38-45 vs. 37-40; and principal anal-fin rays, 18-23 vs. 14-18; and a more triangular pectoral axial scale vs. more lanceolate in N. bottegi (Ref. 121710). Neobola kinondo differs from Engraulicypris moeruensis by its higher numbers of principal anal-fin rays, 18-23 vs. 14, and higher caudal peduncle circumferential scales (Ref. 121710). Neobola kinondo differs from N. nilotica by its lower modal numbers of lateral line scales and principal anal fin rays, 41 and 18 vs. 44 and 22 (Ref. 121710). Neobola kinondo is readily distinguished from N. stellae by its lower count of gill rakers on the first ceratobranchial, 7 vs. 10 (Ref. 121710). Description: Body compressed, depth at dorsal fin averaging 20.9% of standard length, twice as deep as body width at dorsal fin, which averages 10.3% of standard length (Ref. 121710). Head long, averaging 22% of standard length; orbit diameter is large averaging 28% of head length, slightly smaller than interorbital width, which averages 31% of head length; snout short, smaller on average than eye diameter and averaging 26% of head length; mouth large, upturned and terminal, lips equal, extending roughly to anterior third of orbit (Ref. 121710). Pre-dorsal and pre-anal distances long and roughly equal, averaging 63.9% and 62.4% of standard length, respectively; suborbitals broad, covering most of cheek (Ref. 121710). Gill rakers short, seven on the ceratohyal of the anterior most gill arch; pharyngeal teeth in two rows, 4.3, dagger like with hooked tips (Ref. 121710). Dorsal fin short, averaging 10% of standard length, its origin slightly behind anal fin origin, modally with 8 principal rays, fin ray formula ii,7; anal fin long, averaging 23.6% of standard length, modally with 18 principal rays, fin ray formula iii,17; pectoral fin long, averaging 23.4% of standard length, slightly longer than head length and pointed, reaching origin of pelvic fin, modally with 12 principal rays; pelvic fin length 12.3% of standard length, roughly half as long as pectoral fin, modally with 8 principal rays; caudal fin modally with 19 principal rays, 9 in the upper lobe and 10 in the lower lobe (Ref. 121710). Scales thin and highly flexible (Ref. 121710). Caudal peduncle short and narrow, its length averaging 14.2% of standard length and depth averaging 8.9% of standard length (Ref. 121710). Pectoral axial scale small averages 31% of pectoral fin length, with a scalene triangular shape and a fleshy ventral border (Ref. 121710). Colouration: In life, dorsum light brown, with intense silver to white on cheeks, operculum and sides from second scale row on dorsum to ventral body margin; dorsal and pectoral fins unpigmented; pelvic, anal and lower lobe of caudal fin yellow-orange (Ref. 121710). In preservative, the dorsum ground colour is brown lightening to taupe on the upper sides, with a dusting of brown melanophores and myomeres clearly visible through the skin; a distinct lateral stripe, narrow anteriorly and broadening posteriorly, separates the dorsum from the portion of the sides that is intensely silver in life; the silver colour on the cheeks, operculum and sides fades to white in preservative; the fins of preserved specimens are colourless and translucent; the colourless fins and intense silver to white colour on the sides are characters shared by Neobola fluviatilis (Ref. 121710).
Biology:  Found in rivers with swiftly flowing water with large rock outcrops that formed small waterfalls (Ref. 121710). Stomachs dissected from a few specimens were found to contain chironomid larvae, ants, mayflies and various body parts of winged-adult stages of unidentified dipterans (Ref. 121710). Males have breeding tubercles on the top of head, underside of jaws, cheeks, and operculum, with fine tubercles on the pectoral fin and the ventral sides of the body; nuptial males also have an orange patch of pigment in the middle of the lower lobe of the caudal fin (Ref. 121710).
IUCN Red List Status: Vulnerable (VU); Date assessed: 21 July 2020 (B1ab(iii)) Ref. (130435)
Threat to humans:  harmless

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