THE NOTHOBRANCHIUS SITE

ZMB 31417, lectotype, male; Portugiesisch-Ost-Afrika, Beira (present Beira, Mozambique), (19°49.8' S, 34°54.1' E); 2 Jun 1926, deposited by A. Rachow.

ZMB 21389 (2), 21475 (1)

Nothobranchius rachovii is distinguished from other species of the genus by the following combination of characters: in males, a bright colouration consisting of alternating light blue and orange-red bars on the body and fins, orange-red head, and orange subterminal and black terminal bands in the caudal fin (Shidlovskiy et al., 2010).

Subgenus: Nothobranchius s.s.

Species group: N. rachovii group

Nothobranchius rachovii was established as a species by Ahl in 1926, and that status has since been accepted by all authors.

Populations first observed in 1968 in Kruger National Park of South Africa and subsequently in several river drainages in southern Mozambique were earlier referred to as the black form of N. rachovii; whereas populations from the Kwa-Kwa (Cuacua) and Licuare river systems in Mozambique were also regarded as belonging to N. rachovii until Shidlovskiy et al. (2010) published a redescription of N. rachovii, restricting its distribution to the lower Pungwe, lower Zambezi and lower Shire rivers. Populations from South Africa and southern Mozambique, and those from the Kwa-Kwa (Cuacua) and Licuare river systems in Mozambique were described by Shidlovskiy et al. (2010) as N. pienaari and N. krysanovi, respectively.

Portugiesisch-Ost-Afrika, Beira (present Beira, Mozambique), (19°49.8' S, 34°54.1' E).

This species is endemic to seasonal freshwater habitats in eastern Mozambique and southern Malawi. It is known from temporary pools and swamps or water-filled depressions in the lowland floodplains of the lower Pungwe and lower Zambezi Rivers in eastern Mozambique and the lower Shire river system in southern Malawi and the immediately adjacent part of west-central Mozambique.

Lower Zambezi (561)

Zambezian Lowveld (576)

5–101 m

Water parameters are as follows (Watters, personal data; Kearney, personal data): temperature of 26–30°C; pH of 5.8–6.9; conductivity of 200–2020 µS; and typically turbid (Nagy & Watters, 2019).

N. orthonotus - 19%

This species has an annual life cycle.

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

Maximum size reported: 33.4 mm SL (MRAC A4-039-P-0056-0065, males)

Diploid chromosome number 2n = 16 (Post, 1964; Ewulonu et al., 1985; Krysanov, 1992; Shidlovskiy et al., 2010; Safranova & Krysanov, 2015), NF = 30, karyotype structure 8m+6sm+2st/a (Krysanov & Demidova, 2018).

Diploid chromosome number, fundamental number and karyotype structure unique in the genus.

The specific name is given in honor of Arthur Rachow, German aquarist and amateur ichthyologist.

Least Concern (Nagy & Watters, 2019);

Previous assessment: Least Concern (Bills, 2007)

    Ahl, E. 1926. Neue oder selten importierte Fische, III. Blätter für Aquarien- und Terrarienkunde, 37 (14): 346–348. [taxonomy as Fundulus rachovii]

    Paepke, H.-J. & L. Seegers. 1986. Kritischer Katalog der Typen und Typoide der Fischsammlung des Zoologischen Museums Berlin. Teil 1: Atheriniformes. Mitteilungen aus dem Zoologischen Museum in Berlin, 62 (1): 135–186. [lectotype designation]

    Shidlovskiy, K. M., B. R. Watters & R. H. Wildekamp. 2010. Notes on the annual killifish species Nothobranchius rachovii (Cyprinodontiformes; Nothobranchiidae) with the description of two new species. Zootaxa, 2724: 37–57. [morphometrics, phylogeny, systematics, distribution]

    Nagy, B. & B. R. Watters. 2019. Nothobranchius rachovii. The IUCN Red List of Threatened Species 2019: e.T141973907A58311523. [conservation]