Wednesday, April 26, 2023

For real

Even my non fiction includes dead bodies... dead fish to be precise. Today a new article, which includes two new genera and five new species, and which I worked on with Jean Huber (Paris, France) since 2019, is officially published:Meinema, Eduard & Jean H. Huber (2023): Review of Pantanodontidae (Cyprinodontiformes) and its fossil and extant genera Pantanodon Myers, 1955 and †Paralebias Gaudant, 2013 with descriptions of two new recent genera and five new species.- Killi Data series, April 24, 2023: 21-73

To describe Aliteranodon ndoano n.sp., an x-ray of the type specimen of was needed. As NMR (Het Natuurhistorisch / Museum of Natural History, Rotterdam) does not have the equipment to produce radiographs, these fish, barely two centimeters in size, were scanned at the X-ray department at the "neighbors" of the museum: the Erasmus Medical Centre. A lot of hospital staff stopped by to see what was going on. And it was funny to see the tiny specimen in the middle of a hospital bed... (Watch the video on Instagram). The drawing (in process) is of Pantanodon podoxys.

This article also includes notes on fossil species. One of them, overseen by previous workers, was found in 2010 in The Netherlands. Read more about this unique specimen in this blogpost. The fossil notes will be part of a catalog on fossil cyprinodonts (including both egglaying and livebearing killifish). The first edition, scheduled for autumn 2023, will include idealized sketches indicating how the fossil species may have looked like in real life. The series is intended to clarify several misidentifications and uncertainties in order to produce an up to date catalog of all fossil cyprinodonts (first time ever!) including more than 150 species, of which at least 90 are still valid. [Check out details on this catalog here, scroll to the bottom of the page.]

Image above: Aliteranodon ndoano n.sp. (A) male KEN 10-10; (B) female KEN 10-10 (both not preserved); (C) locality KEN 10-09: seasonal pool. Clear water, somewhat brown in color, maximum depth ca. 50 cm; 30.0°C; pH 7.20; total dissolved solids 263 ppm. (D) locality KEN 10-10: brackish water; 30.1°C; pH 7.71; total dissolved solids approx. 22,500 ppm. Photos courtesy: Béla Nagy.

Abstract: Pantanodontinae described by Myers (1955) with monotypic genus (Pantanodon) and species (podoxys) have recently been elevated to family level in Cyprinodontiformes following molecular evidence, and parallelly fossil European cyprinodonts, previously placed in †Paralebias Gaudant 2013, were recently reassigned to the extant East African genus Pantanodon Myers 1955, as the only genus in Pantanodontidae, with all extant and fossil species sharing the laterally placed pelvic girdle and the adaptation of the pelvic fins in males. In this study the status and biogeographical distribution of all species (and all known institutional records) within Pantanodontidae is reviewed. Pantanodon is shown to be a diversified group of related species, recent, extant or fossil. Based on new data, on reassessments of old data and on new diagnoses, a division of Pantanodontidae into four genera is proposed: Pantanodon (nominotypical Tanzanian genus), Malagodon nov.gen. (Malagasy genus), Aliteranodon nov.gen. (Kenyan genus), three genera including (recent) East African species, and †Paralebias which includes all fossil Pantanodontidae European species. Pantanodon podoxys Myers, 1955 is revalidated as a distinct species and a closely related species from Tanga (Tanzania) is described as P. propinquus n.sp. Within Aliteranodon nov.gen., a recently collected species from Koreni (Kenya) is herein described as A. ndoano n.sp. and designated as its type species. Several more species are assigned to this new genus: Haplochilichthys stuhlmanni Ahl, 1924 with which Pantanodon podoxys was previously synonymized is revalidated with a new combination and its type locality is proposed as Pangani, in north-eastern Tanzania, after a detailed review of Stuhlmann’s collecting trips between 1894 and 1901; a misidentified species from Ngomeni (Kenya) is formally described as A. rostratus n.sp. and two misidentified miniature species from Tanzania are formally described as A. bucinus n.sp., from Zanzibar Island, and A. filimbi n.sp., from Bagamoyo mainland. Oryzias madagascariensis Arnoult, 1963 is designated as type species of Malagodon nov.gen.; Haplochilichthys jeanneli Pellegrin, 1935 is reviewed and a lectotype is designated following suspicions it may be placed in Pantanodontidae. Based on five significant osteological differences between recent and fossil species reestablishment of the fossil genus †Paralebias is proposed with a subdivision into three species-groups. For the first time the unique larval stage of A. stuhlmanni and A. ndoano n.sp. is disclosed.