Paramormyrops batessi, BATESII (BOULENGER, 1906)

Rich, Madeline, Sullivan, John P. & Hopkins, Carl D., 2017, Rediscovery and description of Paramormyrops sphekodes (Sauvage, 1879) and a new cryptic Paramormyrops (Mormyridae: Osteoglossiformes) from the Ogooué River of Gabon using morphometrics, DNA sequencing and electrophysiology, Zoological Journal of the Linnean Society 180, pp. 613-646 : 625

PARAMORMYROPS BATESII ( BOULENGER, 1906)

Marcusenius batesii Boulenger, 1906: 36 . Syntypes: BMNH 1906.5.26:159–160. Type locality: Kribi River at Efulen, Cameroon. [Note: Collector George L. Bates probably collected these specimens while at the American Protestant Mission at Efulen (2.7666667°N, 10.7166667°E) located near a small tributary of the Kribi River (now Kienke River)].

Paramormyrops batesii – Hopkins et al., 2007: 298.

PARAMORMYROPS CURVIFRONS (TAVERNE, THYS VAN DEN AUDENAERDE, HEYMER & GÉRY, 1977)

Brienomyrus curvifrons Taverne, Thys van den Audenaerde, Heymer & Géry, 1977: 205 , Fig. 2 . Holotype: MRAC 75.24 -P-132. Type locality: Ivindo River near M’Passa, Makokou, Gabon.

Paramormyrops curvifrons – Hopkins et al., 2007: 304.

PARAMORMYROPS GABONENSIS TAVERNE, THYS VAN DEN AUDENAERDE, & HEYMER 1977

Paramormyrops gabonensis Taverne, Thys van de Audenaerde, & Heymer, 1977: 635 , Fig. 1 . Type species. Holotype MRAC 75-24 -P-6 from Ivindo River near M’Passa, Makokou, Gabon.

PARAMORMYROPS HOPKINSI (TAVERNE & THYS VAN DEN AUDENAERDE, 1985)

Brienomyrus hopkinsi Taverne & Thys van den Audenaerde, 1985:49 , Fig.1 . Holotype: MRAC 84-34 -P- 10. Type locality: Ivindo River near Makokou, Gabon.

Paramormyrops hopkinsi – Hopkins et al., 2007: 294.

Figures

Figure 1. (A) Paramormyrops sphekodes (Sauvage, 1877) MNHN A.893 photographed in 1984 by W. Harder at which time the lot contained two specimens, suspended vertically in a tall jar from a glass floater. The original MNHN catalogue shows two specimens accessioned in 1878 under this number. The larger specimen (SL = 113.8 mm) is currently catalogued as A 893; the smaller specimen (SL = 98.7 mm) was subsequently catalogued in 1998 as MNHN 1050-1998. Sauvage’s original description indicates multiple specimens with a largest of 140 mm total length, but he designated no holotype. We regard these specimens as syntypes prior to our designation of the larger as lectotype. (B) Radiograph of MNHN A893.

Figure 2. Electric organ discharge (EOD) waveforms recorded from 40 specimens of P. sphekodes-like mormyrids from the Ogooué River Basin of Gabon suggest the possibility of two species with distinct EOD waveforms. (A) For each specimen, EOD duration is plotted against standard length (SL). (B) Histogram of EOD durations reveals two modal peaks: one for short EODs, <2 ms duration, and one for longer EODs,> 2 ms. (C) EOD waveforms of longer (above) and shorter duration (below) are superimposed after each EOD’s amplitude is normalized to the same peak-to-peak height and centred on the zero-crossing between positive and negative peaks. Blue lines are males and red lines are females. Head positivity is upward. EOD duration is measured between T1 and T2 (in E), first and last points of the waveform that deviate above or below the baseline by more than 2% of the peak-to-peak height. In previous publications, the longer EOD type was referred to by the code name ‘SN4’. The fish with the ‘short EOD’ waveform is new to this study. (D) Histograms of SLs of all 40 specimens separated by EOD-type and by sex/age class show that within each EOD type there are males recognized by their dimorphic anal fins.Within each group, males tend to have the longest duration waveforms.This sex difference is especially pronounced for SN4 males recorded during the breeding season. Fish of both EOD types co-occur at two sites in Gabon: the main channel of the Ogooué River at Doumé and the Sébé River nearby (see map). (E) EOD waveform of specimen CUMV 98177 tag JPS-1238 showing how EOD duration is measured.