Nothobranchius kuhntae (Ahl, 1926)

Last updated 25/10/2000

Photo 1: pair of N.kuhntae from Roloff 's import in 1958 from BEIRA, MOZAMBIQUE.
{Photograph:
E.Roloff in L. Seegers 1985a, DKG-J Supplementheft 1:4}.

 

kuhntae:

First Description

Ahl, E. (1926): "Neue oder selten importierte Fische, I" - Blätter Aquar. Terra. Kunde, 37:222.

Figure 3: Male of the in 1958 from Beira imported population, the wine red colours
are much more pronounced than in present aquarium strains} - {Photo:
E. Roloff in L. Seegers, 1985a, DKG-J Supplementheft 1:6}.

 

Terra Typica

The Type locality of N.kuhntae was Beira, Mozambique.

History

In 1973 a fish appeared in the DKG under the name N.orthonotus but its status remained unclear for several years as many publications considered N.orthonotus and N.kuhntae to represent one and the same species. In 1975, Jubb published in the Journal of the AKA his "Jubb papers" in which he expressed his views that N.kuhntae (Ahl, 1926) and N.orthonotus (Peters, 1844) were to be considered as two separate species. He noticed that in separating these two species, as well as most of the other Nothobranchius species, the breeding colors of mature males and females are most important and that on these characters alone it was possible to separate N.orthonotus from N.kuhntae (Jubb, 1981).

In 1978 he reiterated the view that from the three Nothobranchius species found in Mozambique and more specifically in the Zambezi and Pungwe River floodplains [N.orthonotus, N.kuhntae and N.rachovii] the sexually mature females of N.orthonotus and N.rachovii do not have spots, neither on their fins nor over their body. On the contrary, adult females of N.kuhntae have numerous small dark red spots spread over their flanks, dorsal and anal fins (Jubb, 1978). During a first identification in 1973, Jubb (1973) could however not come to a conclusive decision as to the species' status.

In nature, N.kuhntae can be found in the floodplains of the Pungwe river, from Villa Machado [3420'E - 1920'S] until Beira and towards the northeast the swamps and floodplains near Quelimane [3650'E - 1750'S] (Jubb, 1978). The conceiver of the Nothobranchius genus Dr. Wilhelm Peters, Berlin, explored from 1842 to 1848 the lower Zambezi in Mozambique, from its mouth upstream until Tete. In 1868, Peters published his "Reise nach Mossambique". In this work he described and illustrated with much dedication the fishes he had collected in the Mozambican waters. In order to be able to categorise his species orthonotus, which he had collected in 1844 in the swamps near Quelimane, he proposed the new genus Nothobranchius. In his discussion about orthonotus he even stated "fried, they make up an excellent dish".

Considering that in the mid-seventies the name N.orthonotus had been and still was extensively used in the aquarium literature to define several different Nothobranchius species, Jubb (1978) got interested to re-discover Peters' real N.orthonotus. In his quest he received strong support from Mr. Stuart Grant [exporter of tropical fish from Malawi] and from Mr. H. Affleck, a veterinarian who worked in Mozambique and was stationed near Quelimane. The Type-locality as given by Peters in 1868 corresponded to a swampy area connected to either the Kwakwa River or to the Quelimane River, a hydrological system that lies west of Quelimane and which depends on the Zambezi floods for its seasonal flooding (Jubb, 1978). The entire lower Zambezi with his extensive floodplains can be considered as a single vast ecosystem. Mr. Grant collected N.orthonotus in the floodplains of the lower Shire River, near Chiromo in Malawi [3520'E - 1630'S].

With the description, photographs and collected material provided by Mr. Grant together with the description and collected material provided by Mr. Affleck, Jubb (1978) was able to re-discover the real identity of Peters' orthonotus and to compare this new material with the Type specimen held in the Berliner Museum, Germany. Jubb (1978) also obtained specimens from Mr. D. Plowes from Zimbabwe, who collected in 1970 the floodplains of the Pungwe River; from Mr. Donnelly, an ichthyologist who collected in 1973 in the floodplains near Beira, Mr. Kirk who collected around Lake Chilwa in Malawi and Dr. Furzer who collected in the Gona-Re-Zhou game Reserve near the border with Mozambique and Zimbabwe. More towards the south, Jubb was provided with specimens collected by Dr. U. de Pienaar in the Krüger National Park and Mr. Kok from Natal University who collected the floodplains of the Pongolo River. Thanks to these different collections Jubb (1978) believed he was finally able to clarify the real identity of N.orthonotus and N.kuhntae in Mozambique.

Meristic & Morphometric data

D= 14-16; A= 13-15; Scales along longitudinal line series: 28-30, 26-28 scales around the body in front of the ventral fins (Jubb, 1981)

The origin of dorsal lies over the origin of the anal fin and the insertion of the dorsal fin lies midway between origin of middle rays of caudal fin and posterior edge of preoperculum (Jubb, 1981).

Karyotype: n=?

Synonymes

Fundulus kuhntae Ahl, 1926
Adiniops troemneri Myers, 1926
Nothobranchius "U-05"
Nothobranchius "Beira 91"

Arrived in Germany from the USA in 1973 under the name "N.orthonotus U-05" {Gimplinger, 1978}.

Many authors considered N.kuhntae to represent a mere color variation of N.orthonotus. Recently, there has been a tendency to revert from this hypothesis (Rosenstock, 1995:165).

Jubb (1981) considers that Nothobranchius troemneri, described by Myers in 1926, is also a synonym of N.kuhntae.

Holotype

 

Size

Mature males of N.kuhntae do not reach such a large size as those of N.orthonotus. They are more vividly colored and the females are spotted with red. Radda (1981:4) reports a maximum total length of 65 mm. Rosenstock reports a maximum length of 60-65 mm, but that it definitely also can reach 70 mm (Rosenstock, 1995:166).

Code

 

Distribution & Habitat

In Mozambique and more particularly in the Zambezi and Pungwe River floodplains one can find three different Nothobranchius species: N.orthonotus, N.kuhntae and N.rachovii (Jubb, 1978). In nature, N.kuhntae can be found in the floodplains of the Pungwe River, from as far west as Vila Machado {3420'E - 1920'S} to Beira and northeast of the swamps and floodplains near Quelimane {3650'E - 1750'S} (Jubb, 1978). It is found in floodplains and swampy areas, which provide suitable seasonal habitats. It occurs together with N.orthonotus or with N.rachovii in certain places (Jubb, 1981). The fact that N.orthonotus and N.kuhntae occur sympatric in the vicinity of Beira may account for the yearlong confusion between both species when dealing with preserved material, but living specimens can hardly be confused.

The known distribution area of N.kuhntae extends from the swamps west of Quelimane; the floodplains of the lower Zambezi and the floodplains of the lower Shire river, where it is being found together with N.rachovii; the temporary pools within the Gona re Zhou Game Reserve in Zimbabwe, where it is being found together with N.furzeri; to the south in temporary pools within the Krüger National Park, South Africa; and finally within the floodplains of the Pongolo River system, Kwazulu, Northern Natal.

Bowmaker et al. (1978) mentions the occurrence of N.kuhntae in the Buzi and Pungwe river drainage basins.

Watters (1998) reported that the N.kuhntae Beira 91 and 98 where collected from the same locality, as where some N.rachovii. The Beira 91 population is still in the hobby and the Beira 98 population was made of only one single trio, which he received and was able to spawn.

Considering this wide distribution area, it is a highly variable species, which in future possibly could be split into several under-species. Presently, it is however still considered as a polytypical species

Description

N.kuhntae has a rather elongated body shape, quite similar to N.furzeri.

Males: under appropriate light, the carmine to bright red caudal and anal fins with darker red spots of courting males are astonishing and in sharp contrast to the turquoise-green sides and the dark red spotted throat region. The lower lip is deep red as well as the external half of the pectoral fins. The dorsal fin is heavily marked with carmine red, red or reddish brown spots, along the extremity of the fin runs an intense white or sky blue marginal band, which however are only clearly marked in particularly colored males. The caudal fin is entirely carmine red or reddish brown with a pale to sky blue or white edge sometimes present. The anal fin is pale olive near its base with carmine red to reddish brown spots forming a solid band towards the extremity. The anal fin is edged with white or pale to sky blue. Ventral fins are carmine red with a pale blue border whilst the pectoral fins are transparent to pale pink with a dark red edge. The body color is yellowish and each scale is edged with carmine red or reddish brown forming a reticulation pattern over the entire body, especially pronounced in the rear part of the body. The scale centers are iridescent sky blue or turquoise. The head is covered with carmine red spots and sexually active males have red to brilliant red spots over their gill cover [operculum]. The eye iris is golden with a dark vertical stripe through the eye. The gill cover and pre-gill cover are iridescent sky blue o pale olive with numerous scattered, prominent carmine red to reddish brown dots on cheeks, chin and head.

Females: females can not display the male coloration, they have a rather dull to pale olive-gray body coloration. However they distinguish themselves from other Nothobranchius females by their small, round, red-black points or dots, which are irregularly distributed over the sides, between dorsal and anal fins, over the posterior part of the body. The unpaired fins are also covered with many similar but smaller spots. The ventral surface is yellowish white. Scales have narrow black edges. The head has a few black dots. [In live fish the presence of red spots separates the females of N.kuhntae from those of N.orthonotus, which are not spotted (Jubb, 1981).

Breeding & Maintenance

N.kuhntae has never been and probably will never be a very commonly available species in the hobby. Contemplating the species on offer over the years showed that where in the seventies it was available once or twice per year, in the eighties and nineties it hardly ever appeared again. The reason for this is supposedly the un-overwhelming colours of the species. According to Gimplinger (1978), this is probably correct when contemplating the fish in a wholesaler's tank, but is assuredly not the case when the fish is brought under the correct lighting and over a correct substrate.

It was first imported in Stuttgart, Germany, in 1973 from the USA under the name Nothobranchius "U 5".

They have similar requirements as the other Nothobranchius species: water with about 10DH hardness is sufficient. Most presently kept aquarium populations of various Nothobranchius species seem to have adjusted quite well to most of our hard tap waters {=calcium-magnesium rich water} Gimplinger (1978).

Concerning the incubation time for the N.kuhntae eggs, Gimplinger (1978) mentions that the about 1-mm large eggs require, depending on the prevailing conditions in one's own storage room, between 7 and 8 months of dry incubation period. The incubation time is of course in relation to the maintenance temperature, the oxygen content and availability in the bags as well as to the humidity level of the peatmoss {each hobbyist should observe and master his own incubation environment}. Gimplinger (1978) obtained above mentioned incubation times with relatively wet peatmoss, when the collected peatmoss was not submitted to a rapid drying-up after collection and by conservation temperatures kept between 28-30C [82-86F]. At lower temperatures [20C or 68F.] and with wet peatmoss {still looking dark brown} one will have to consider even longer incubation times (Gimplinger, 1978).

When developed and poured into fresh water, the eggs will hatch within only a few hours. The young are relatively large in contrast to the small size of the eggs {comparable to young of N.guentheri or N.furzeri} and immediately can take freshly hatched Artemia nauplii.

Gimplinger (1978) further mentions that compared to most other Nothobranchius species N.kuhntae appears to be a short-lived species with a life expectancy similar to N.furzeri.

Bibliography