THE NOTHOBRANCHIUS SITE

UFRJ 6661, holotype, male, 23.1 mm SL; Tanzania: District of Pawani: seasonal pool at the left bank of the Mbezi River, road between Mkuranga and Kibiti, near the village of Kitonga, 07°11'14'' S, 39°10'18'' E; collected by W. J. E. M. Costa, B. B. Costa, C. P. Bove, M. A. Barbosa & P. Bragança, 10 Jan 2009.

UFRJ 6662 (1), 6663 (2, c&s), 6664 (1), 6665 (1, c&s)

Nothobranchius ruudwildekampi males are similar to N. korthausae and distinguished from the remaining congeners by the combination of traverse bars on the caudal fin, white distal margins to the dorsal and anal fins, and a blue blotch on the distal portion of the pectoral fins in males. Nothobranchius ruudwildekampi is distinguished from N. korthausae by having minute horizontally elongated dark gray spots on the posterior portion of the pectoral fin in males, absence of subdistal black bars on the unpaired fins in males, absence of a white distal margin on the caudal fin in males, 7–9 red-brown bars on the anal fin in males, and 27–29 caudal-fin rays (after Costa, 2009).

Subgenus: Adiniops

Species group: N. guentheri group

Following its discovery on the coastal mainland of Tanzania in 2000, the several populations that were found had been referred to as N. korthausae, a species known only from Mafia Island off the coast Tanzania, and which showed close similarities in male colouration. The mainland populations were subsequently described by Costa (2009) as N. ruudwildekampi, thereby restricting the distribution of N. korthausae again to the originally defined Mafia Island.

Tanzania: District of Pawani: seasonal pool at the left bank of the Mbezi River, road between Mkuranga and Kibiti, near the village of Kitonga, 07°11'14'' S, 39°10'18'' E.

This species is endemic to seasonal freshwater habitats in coastal Tanzania. It is known from seasonal pools and swamps in the drainages of the Mbezi, Luhule/Luhute river systems, and a minor stream system associated directly with the northern marginal zone of the Rufiji delta, in coastal Tanzania.

Coastal East Africa (564)

1–74 m

Personal observation at collecting sites:

Water temperature: 27.8–32.4 °C

pH: 7.19–7.64

TDS:  156–222 ppm

Conductivity: 312–444 µS

N. melanospilus - 60%

N. luekei - 40%

N. rubripinnis - 36%

N. lucius - 20%

N. albimarginatus - 12%

N. lourensi - 4%​

This species has a semi-annual life cycle.

Embryonic development under captive conditions in peat moss is about two to three months at room temperature.

Maximum size reported: 24.9 mm SL (UFRJ 6665, male)

Diploid chromosome number 2n = 36, NF 38, karyotype structure 2m+34st/a (Krysanov & Demidova, 2018).

Diploid chromosome number and karyotype structure shared with some other members of the N. guentheri species group in Adiniops subgenus.

The specific name is given in honor of Ruud Wildekamp, in recongition for his fine taxonomic work on the genus Nothobranchius.

Vulnerable B1ab(iii) (Nagy & Watters, 2019)

    Costa, W. J. E. M. 2009. Species delimitation among populations of the eastern Tanzanian seasonal killifish Nothobranchius korthausae (Cyprinodontiformes: Nothobranchiidae). Ichtyological Exploration of Freshwaters, 20 (2): 111–126. [taxonomy as Nothobranchius ruudwildekampi]

    Nagy, B. & A. Horváth Kis. 2010. Variation in habitat characteristics and the occurrence of Nothobranchius species in seasonal biotopes of Tanzania. Journal of the American Killifish Association, 43 (5): 130–144. [ecology]

    Nagy, B. 2010. A la recherche de killis sur l’île de Pemba et dans la partie côtière de la Tanzanie. Killi Revue, Killi Club de France, 2010 (5): 3–11. [collecting]

    Nagy, B. 2015. Life history and reproduction of Nothobranchius fishes. Journal of the American Killifish Association, 47 (4-6): 182–192. [ecology]

    Watters, B. R., B. Nagy, P. D. W. van der Merwe, F. P. D. Cotterill & D. U. Bellstedt. 2019. Review of the Nothobranchius taeniopygus species group from central and western Tanzania with descriptions of five new species and redescription of Nothobranchius taeniopygus (Teleostei: Nothobranchiidae). Ichthyological Exploration of Freshwaters, IEF-1110, pp. 1–41. [phylogeny]

    Nagy, B. & B. R. Watters. 2019. Nothobranchius ruudwildekampi. The IUCN Red List of Threatened Species 2019: e.T53904446A58340389. [conservation]