Morphology Data of Parakneria alytogrammus
Identification keys
Abnormalities
Main Ref. Kiwela Mutambala, P., E. Abwe, F.D.B. Schedel, A. Chocha Manda, U.K. Schliewen and E.J.W.M.N. Vreven, 2022
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs
Different appearance
Different colors
Remarks

Descriptive characteristics of juvenile and adult

Striking features
Body shape lateral
Cross section
Dorsal head profile
Type of eyes
Type of mouth/snout
Position of mouth
Type of scales
Diagnosis

Diagnosis: From all its congeners in the Congo Basin in general and the Upper Lualaba and Luapula-Mweru systems in particular, Parakneria alytogrammus differs by the combination of its lower number of transversal bands on each of the caudal-fin lobes, 2 vs. 3-5, and the presence of an uninterrupted lateral mid-longitudinal black band in fresh and preserved specimens vs. either a lateral mid-longitudinal band interrupted and forming a series of more or less rounded black spots in other species except in Parakneria damasi; in the latter species a lateral mid-longitudinal band with spots not very clearly separated is documented (Ref. 127997). It further differs from the three Parakneria species currently known from the Upper Lualaba basin, P. damasi, P. lufirae and P. thysi, by the narrow base of its pectoral fin, 4.8-5.6% of standard length vs. 8.2-10.1% for P. lufirae, 8.6% for P. damasi and 7.6-7.9% for P. thysi; in addition, it also differs from P. damasi only by its short pectoral fin, 18.6-18.9% of standard length vs. 24.5%, high head height, 49.2-52.9% of head length vs. 45.2%, and short pelvic fin, 15.0-15.4% of standard length vs. 17.8%; and by the low number of pectoral-fin rays, 16-17 vs. 20; likewise, it also differs from P. lufirae only by its narrow mouth width, 29.7-30.4% of head length vs. 34.6-43.7%, and its short pectoral fin, 18.6-18.9% of standard length vs. 21.2-23.6%; in addition, it also differs from P. thysi by the lack of black vertical blotches below the lateral mid-longitudinal black band vs. present in P. thysi (Ref. 127997). In addition, it differs from P. malaissei, the only species known from the Luapula-Mweru system, by its dorsal and pelvic fins being closer to the caudal-fin base, i.e. by a short post-dorsal distance, 36.4-36.6% of standard length vs. 38.6-41.1%, and a short post-pelvic distance, 40.0-40.6% of standard length vs. 41.4-44.1% (Ref. 127997). Furthermore, P. alytogrammus differs from the remaining Congo basin congeners, except P. abbreviata, by the narrow base of its pectoral fin, 4.8-5.6% of standard length vs. 8.7% for P. vilhenae, 7.1-8.1% for P. kissi, 7.6-7.8% for P. ladigesi and 6.7-8.0% for P. cameronensis; it differs from P. kissi by the high caudal peduncle height, 7.7-8.4% of standard length vs. 7.2%, the high number of total and caudal vertebrae, 41-42 and 12-13 vs. 38 and 10, and by its short pelvic-anal distance, 20.8-21.8% of standard length vs. 23.0-23.9%; it further differs from P. vilhenae and P. cameronensis by its short pectoral-fin length, 17.4-19.0% of standard length vs. 24.4% for P. vilhenae and 20.8-23.8% for P. cameronensis; and from P. cameronensis and P. ladigesi by its deep head height, 49.2-52.9% of head length vs. 41.2-43.2% for P. cameronensis and 40.5-43.4% for P. ladigesi; finally, it also differs from P. abbreviata by the high number of scales on the lateral line, 90-98 vs. 75-76 (Ref. 127997). Lastly, P. alytogrammus differs from P. fortuita, its only currently known congener from southern Africa by having a continuous black band along the lateral line, the presence of a vertical transverse band at the base of the caudal fin vs. two spots, the one behind the other at the base of the caudal fin, the last one being larger than the first one, a well indented caudal fin with two pointed lobes, vs. a moderately indented caudal fin, with two more or less rounded lobes, and a slightly more backward position of its pelvic fin, i.e., inserted below the fourth dorsal-fin ray, vs. pelvic fin inserted below the third dorsal-fin ray; in addition, P. alytogrammus differs from P. fortuita by a short post-pectoral distance, 72.8-73.8% of standard length vs. 77.3%, and a deep body height, 13.5-14.8% of standard length vs. 10.3% (Ref. 127997).

Description: Slightly concave dorsal profile from snout tip to caudal-fin insertion and with similar pre- and post-dorsal curvature; ventral body surface mor or less straight (Ref. 127997). Snout pointed, mouth narrow with both lateral limits marked by an outgrowth in the form of a pointed bullet; space between nostrils and tip of snout with an arch of 10 pores visible as small dots; free posterior opercular margin situated shortly behind level of anterior base of pectoral fins (Ref. 127997). Pelvic fin insertion below the fourth dorsal ray; caudal fin is well indented, i.e., over about two-fifths of its horizontal length, with its lower lobe slightly longer than its upper lobe (Ref. 127997). Specimens with 41-42 vertebrae, which are arranged in 16 pre-dorsal, 29-30 pre-anal, 14-15 vertebrae between anterior base of dorsal and anal fin, 25-26 post-dorsal and 12-13 post-anal vertebrae (Ref. 127997).

Colouration: In life, overall background colour light brown, yellowish-green, with a series of fairly faint, dark-grey or black transversal bands on the upper half of the body and a continuous black band along the lateral line; the band starts on the snout, continues over the eye level and the upper level of the operculum, and extends longitudinally on the body up to the caudal-fin base; it is situated just below the lateral line at the level of the operculum and on the lateral line itself from the level of the anterior base of the dorsal fin onwards to the base of the caudal fin; the black band is bordered towards its upper edge by a rather faint, narrow, yellow-green band; the lateral line itself is whitish yellow in colour; the dorsal surface of the body is rather greenish with fairly faint dark-grey or black transversal bars; these bars are narrower on the pre-dorsal part than on the post-dorsal one, in contact with the black longitudinal band and sometimes forked on the pre-dorsal part of the body and clearly more saddle-like, i.e. rounded and not in contact with the black longitudinal band, on the post-dorsal part of the body; a whitish ventral surface of head, body and caudal peduncle; the upper lateral side of the head, i.e. from the ventral level of the eye to the dorsal surface of the head, is blackish; eye has a dark-brown iris, except for its ventral quarter, which is whitish and with a thin, yellowish-orange edge around the pupil; the upper half of the opercular region is marked by a large black spot, resulting from the extension of the lateral mid-longitudinal black band, also marked by small greenish-yellow highlights; the lower half of the opercular region is whitish; pectoral, pelvic and anal fins more or less whitish, colourless, translucent or even transparent with orangish bases; caudal fin has two oblique black bands on each lobe, with the first ones on both lobes touching each other and forming a semi-circle; its base is marked by a black vertical band that almost touches both the dorsal and ventral midline of the caudal peduncle (Ref. 127997). Preserved specimens have a beige overall body colour; the dorsal surface of the pre-dorsal region usually has a black longitudinal band on the dorsal mid-longitudinal line, with three to four black spots in a continuous row in some specimens; eyes entirely black; the opercular region is marked by a rather blackish spot on its upper half and its lower half becoming silver; the ventral side of the head and body is light yellow or white in colour; most of the vivid colours disappear after preservation, instead the lateral mid-longitudinal black band, slightly paler in the anterior region and darker in the posterior region, and the vertical areas on the caudal fin are conserved (Ref. 127997).

Ease of Identification

Meristic characteristics of Parakneria alytogrammus

Lateral Lines Interrupted: No
Scales on lateral line 90 - 98
Pored lateral line scales
Scales in lateral series
Scale rows above lateral line
Scale rows below lateral line
Scales around caudal peduncle
Barbels
Gill clefts (sharks/rays only)
Gill rakers
on lower limb
on upper limb
total
Vertebrae
preanal
total 41 - 42

Fins

Dorsal fin(s)

Attributes no striking attributes
Fins number 1
Finlets No. Dorsal   
Ventral  
Spines total 0 - 0
Soft-rays total 11 - 11
Adipose fin absent

Caudal fin

Attributes forked; more or less normal

Anal fin(s)

Fins number 1
Spines total 0 - 0
Soft-rays total 9 - 9

Paired fins

Pectoral Attributes  more or less normal
Spines     0
Soft-rays   17 - 19
Pelvics Attributes  more or less normal
Position    abdominal  beneath origin of D1
Spines     0
Soft-rays   10 - 10
Back to Search
Comments & Corrections
cfm script by eagbayani, 17.10.00, php script by rolavides, 13/03/08 ,  last modified by sortiz, 06.27.17