Manta birostris
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publication ID |
https://doi.org/10.11646/zootaxa.1717.1.2 |
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DOI |
https://doi.org/10.5281/zenodo.16045104 |
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persistent identifier |
https://treatment.plazi.org/id/5B7C87E2-FF95-FFD1-FF17-FB89FAD00D70 |
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treatment provided by |
Felipe |
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scientific name |
Manta birostris |
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South African specimens View in CoL
South African specimens were all described externally before morphological measurements were taken or dissections were made. The dorsal surfaces were black in colouration with two pale patches on the dorsal medial surface ( Fig. 2a View FIGURE 2 ) and on the posterior halves of the pectoral fin tips. The ventral surface of all specimens were cream-coloured with small black spots on the ventral surface between the gill slits, centrally above the cloaca and extending outwards for approximately half of the posterior section of the pectoral fin ( Fig. 2b View FIGURE 2 ). All specimens exhibited small, dark, semi-circle shaped patches of colouration posterior to both the fifth gill slits. Light charcoal-coloured streaks were present along the posterior edges of the pectoral fins. All umbilical attachments were entirely closed and whitish in coloration. Tails were thin, with black colouration on the dorsal surface and cream on the ventral surface. No caudal spines were present ( Fig. 2c View FIGURE 2 ), but small depressions were found at the base of the tail. Dermal denticles were evenly distributed across the disc. Eyes with distinctly blue irises. Cephalic lobes rolled spirally outwards (bases of the lobes rolling outwards). Lower jaws possessed tooth bands ranging from 58–77% of the width of the mouth. The upper jaw was edentate.
The three South African specimens ranged in size from 2230–2370 mm disc width (DW) and were 71–75 kg in mass. Detailed morphometric measurements are listed in Table 1 View TABLE 1 . The single male examined had small, uncalcified claspers. Internal examination revealed that all three rays were immature as they exhibited undifferentiated reproductive organs. The spiral valves had 44 turns. The livers were bi-lobed, pink in colour with masses of 3.9 kg, 5.3 kg and 6.4 kg (2370 mm DW female, 2230 mm DW female and 2230 mm DW male, respectively).
Mozambican foetal specimen
The pectoral fins of the foetus were folded dorsally over the body ( Fig. 1b View FIGURE 1 ). Uncurling the pectoral fins facilitated further observations and morphometric assessment. The ventral surface was cream-coloured with small black spots on the mid-ventral surface from between the gill slits to above the cloaca ( Fig. 1c View FIGURE 1 ). Small charcoal-coloured semi-circular patches were present posterior to both the fifth gill slits ( Fig. 1c View FIGURE 1 ). Faint charcoal-coloured streaks were present along the posterior edges of the pectoral fins. There was a pink tinge to the ventral surface. The dorsal surface was black with paler coloration on the pectoral fin tips ( Fig. 1a View FIGURE 1 ). Other small pale patches on the mid to rear dorsal surface were noted where black pigment had clearly been removed. The anterior margins of the cephalic fins were grey to black in colour, with grey tips on the medial surface. The umbilical attachment was open, 10 mm in diameter and red in colour ( Fig. 1d View FIGURE 1 ). The tail was long and unbroken. No caudal spine was present at the base of the tail. Dermal denticles were patchily distributed on both the dorsal and ventral surfaces of the body, with slightly larger denticles on the ventral surface. Denticles were sparse on the pectoral margins on both surfaces. The lower jaw possessed a fully formed tooth band ( Fig. 1e View FIGURE 1 ).
The foetus measured 1328 mm straight-line disc width (DW) and weighed 15.1 kg. Detailed morphometric measurements are listed in Table 1 View TABLE 1 . The liver mass was 1100 g. The iris was blue in colouration. Claspers were small and uncalcified ( Fig. 1f View FIGURE 1 ). No internal yolk sac was present. The spiral valve had 44 turns.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.