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
Author
Rich, Madeline
Author
Sullivan, John P.
Author
Hopkins, Carl D.
text
Zoological Journal of the Linnean Society
2017
2017-05-05
180
613
646
journal article
3432
10.1093/zoolinnean/zlw004
7e1fd8ac-534b-4a96-8252-1679b0723fe1
0024-4082
5711034
C93D204F-FFF4-4C9B-AD05-52DDF9298384
KEY TO THE SPECIES OF
PARAMORMYROPS
FROM
LOWER
GUINEA
Combined with the summary figure (
Fig. 16
) this key can be used to distinguish among seven described and one undescribed species of
Paramormyrops
from
Lower
Guinea
.
P. retrodorsalis
(Nichols & Grissom, 1917)
,
P. tavernei
(
Poll, 1972
)
and
P. jacksoni
(
Poll, 1967
)
are excluded here as they reside outside this region.
1. Te e t h b i c u s p i d, 7 i n u p p e r j aw, 8 i n l o w e r jaw……...............................………………
P. hopkinsi
Teeth bicuspid,
5 in
upper jaw,
6 in
lower jaw……2
2. 16 or more scales around the caudal peduncle ........…...............………………………………………..3
12 scales around caudal peduncle.....……… ……………………………………………................…..5
3. Lower jaw profile straight, submental swelling reduced or absent…..………………………………….4
Lower jaw profile concave, submental swelling present..……………………..
Paramormyrops batesii
Figure 13.
Variation in
P. ntotom
sp. nov.
illustrated by five specimens from the Ogooué River: CUMV 96811 tag number JPS-1117, female, 117 mm; CUMV 98091 tag number JPS-1175, male 130 mm SL; CUMV 98092 tag number JPS-1176, male, 154 mm SL; CUMV 98134 tag number JPS-1185, male, 176 mm and CUMV 98136 tag number JPS-1187, male 165 mm.
4. Pre-dorsal distance 58–62% SL; CPL 20.7–25.5% SL…………………………………...………..
P.
sp.
OFF
P D D 5 5. 3 – 5 9. 4 % S L; C P L 2 4. 2 – 2 9. 8 % SL…………………………..…………
P. longicaudatus
5. Head profile blunt or U shaped when viewed from above……………..……………............................……6
Head profile sharp or V shaped when viewed from above…...........................…………………………......7
6. Forehead slightly concave viewed from side; HL 24.9–27.6% SL; caudal peduncle slender, its depth 3.7–4.7% SL; interorbital distance 110–133% SNL…….........................................……
P. gabonensis
Forehead rounded: HL 19.5–28% SL; caudal peduncle depth 4.1–7.5% SL; interorbital distance 121– 202% SNL………………………………..
P. kingsleyae
7. Upper profile of head downward sloping, slightly c o n c a v e: m o u t h s u b t e r m i n a l: P r e -p e c t o r a l
Figure 14.
Electric organ discharges (EODs) from
P. ntotom
sp. nov.
EOD waveforms plot voltage versus time. Voltage is normalized by setting the peak-to-peak voltage to 1.0 V. The time base is in (C). (A) EOD of holotype, CUMV 98138 tag number JPS-1189, male, SL 178 mm. The first peak, P1, is head-positive and the second, P2, is head-negative. Overall duration is 5.813 ms, measured between the two red dots. The 20× expanded trace (black) indicates the absence of a head-negative phase preceding P1. Abbreviations are as in Figure 10. (B) Time derivative of EOD shown in (A), indicating two points where
dV/dt
goes through a local maximum leading to inflection points in the EOD (dashed lines). (C) Superimposed EODs from 18 males (blue) and 13 females and juveniles (red) show a clear sex difference in EOD duration. (D) Power spectrum of the EOD of holotype, with magnitude measured in dB relative to the peak power plotted against frequency in Hz. Frequency at peak power indicated by
F
max.
The frequencies where the magnitude of the power spectrum drops 3 dB below the peak power are indicated by
F
low
and
F
hi
. (E) Superimposed power spectra of traces shown in (C) demonstrate that spectral power emphasizes higher frequencies among females compared to males, as expected.
distance large, PPCD more than 3 7 % SL