A new Cichlid from lake Tanganyika:

Julidochromis dickfeldi sp. N. (Staeck 1975).

(Pisces, cichlidae)
The new cichlid fish of the genus Julidochromis, described in the following account was collected in January 1975 during the course of a study on the fishes of the Zambian part of lake Tanganyika, undertaken by a group of German ichthyologists and aquarists in the region of Sumbu national park.
Although a total of specimens were collected, the number of fishes available for mesuration was very small, as twelve of them were carried alive to Europe. The rest, which died shortly after the capture, were for the most part in such bad condition that they could not be used for the description, which is consequently based only on tow specimens of 65,9 (holotype) and 62,4 mm (paratype) in standard length. The holotype and paratype (figures in brackets) are deposited in the collection of muse royal de l’afrique centrale at Tervuren (reg. Nos 75-23-P-1 and 2).
 
DESCRIPTION
Maximum depth of body 4,61 (4,52) times, length of head 3,56 (3,23) times in the standard length. Body elongated, 1,18 (1,33) times as deep as broad.
Head 1,78 (2,03) as long as broad, with convex upper profile; snout 2,58 (2,38) times in length of head and 1,51 (1,93) times as long as the diameter of the eye, which is 4,30 (4,60) times in length of head and 1,58 (1,48) times in interorbital width. Interorbital width 2,72 and 1,58 (1,48) times in interorbital width. Interorbital width 2,72 (3,11) times in length of head.
Mouth narrow, extending to below nostril. Lower jaw 4,20 (6,23) times in the length of head and much shorter than upper jaw. Teeth very small, conical, forming a villiforme band in each jaw with
Canines in front, the outer of witch are large and strongly curved. Gills rakers short, four on lower part of anterior arch. Dorsal XXIV 5; soft rays longer than spines; longest spine 2,01 (2,22), longest soft ray 1,65 (2,12) times in length of head. First spine very short.
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Pectoral 1,46 (1,69) times in length of head 5,19 (5,47) times in standard length. Ventral extended into a filament, reaching or passing the origin of anal. Caudal rounded. Caudal peduncle 1,69 (1,71) times as long as deep. Anal papilla short, not exceeding 1 mm in length.
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Scales ctenoid, very small on nape, thorax, and anterior part of the back. Operculum and pre-operculum partly covered with very small scales.
 
Total length of holotype 76,5 mm (paratype 70,7 mm). Largest know size 85 mm in total length.
As there are only two preserved specimens of species, it was not thought advisable to make an examination of the internal characteristics.
COLOUR
General body colour brown, in the lower half of the sides frequently with a bluish or sooty sheen. Lower half of head fawn. On the snout and occiput several irregular black cross bars and spots. With three black longitudinal stripes on each side of the body. One from the end of the snout to the base of caudal, a second from the upper margin of the eye to the upper edge of caudal, a third along the base of dorsal fin.
On the cheeks and between the eye and the posterior rim of the operculum the lowermost of these stripes is edged with metallic blue. Upper half of iris metallic green, lower half black. Pectorals transparent. Other fins dusky grey, frequently with a bluish sheen. Dorsal, anal, and caudal with small fawn spots and bright bleu edges. In preserved specimens the body colour tends to become grey or whitish.
OCCURRENCE AND BEHAVIOR
Within an examined coastal strip of about 80 km in total length the occurrence of the new Julidochromis was limited to a few kilometres of rocky shore between cape Kachese and cape Kamwankoko, i. E. north and south of the mouth of the Mugela river.
It lives in shallow water, at depth of one to three meters.
 Field observations with goggles, snorkel, and flippers proved that this cichlid is fairly common in the described habitat. It is, however, difficult to detect and even more difficult to catch, as it always moves in close contact with the rocks and immediately withdraws under stones or into crevices if disturbed. For the most part strictly territorial fish is distributed in pairs over its habitat. The focal point of its territory is a cave, on the roof of witch the eggs are deposited. It frequently lives side by side with Julidochromis regani, although the latter species generally prefers deeper water.
RELATIONSHIP
At present the genre Julidochromis is composed of two different species-groups, witch differ both of them morphologically and ecologically and constitute two different evolutionary lines. Both of them comprise two closely related species. One of these species-groups is composed of Julidochromis regani and J. marlieri, the other of J. ornatus and J. transcriptus.
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Matthes (1962) points to the feat that the two forms of each species-group might possibly be taken to represent only two subspecies, for a few specimens were found, which seem to be intermediate forms between the two members of cache of the different lines.
 In the present state of our knowledge it seems rather difficult to give the new form a satisfactory classification within the Genus Julidochromis. Apart from its body and its caudal peduncle, which seem to be more elongated, there are on the basis of morphologic features no real grounds to justify recognition as a distinct species, for it is more or less identical with both J. ornatus and J. transcriptus.
It shown to be distinct, however, by its coloration and by features of its ecology. J. ornatus and J. transcriptus generally live in the intermediate zone between the rocky and the sandy shore, while J. regani and J. marlieri  prefer a rocky biotop (cf. Matthes 1962). The tact that J. dickfeldi was only found in a rocky habitat, in which it frequently co-existed with J. regani, seems to indicate that this species occupies an ecological niche, differing from that of the other two members of its species-group. In the present state of our knowledge we, therefore, think it best not to consider the three forms of this line conspecific, but to maintain the hitherto existing classification by distinguishing J. ornatus and J. transcriptus specifically and adding the new form as another species. It is named after all dickfeldi, whose idea it was to undertake the expedition to Zambia.

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