Carcharias cuspidatus (Agassiz, 1844)

Hovestadt, Dirk C. & Da Silva, Carlos M., 2025, A new chondrichthyan (Sharks and Rays) Fossil Assemblage from the Miocene Cacela Fm. at Albufeira (Algarve, Portugal) with two new species: Palaeoecology and Biogeography, Zootaxa 5724 (1), pp. 1-66 : 13-14

Carcharias cuspidatus (Agassiz, 1844)

Plate 2, Figs 1–6

* Lamna ( Odontaspis) cuspidata Agassiz 1844: 290 , pl. 37a, figs 43–50.

Lamna ( Odontaspis) denticulata Agassiz 1844: 291 , pl. 37a, figs 51–53.

Lamna ( Odontaspis contortidens Agassiz, 1843 [ sic]— Probst 1879: 144, pl. 2, figs 33–39.

Odontaspis cuspidata var. hopei (Agassiz, 1844) — Priem 1906: 197, pl. 8, figs 5–10.

Odontaspis cuspidata L. Agassiz, 1844 — Leriche 1910: 286, pl. 15, figs 1–21.

Odontaspis acutissima (Agassiz, 1844) mut. vorax Le Hon, 1871 — Leriche 1926: 394, pl. 8, figs 5–10.

Odontaspis cuspidata (Agassiz, 1844) — Weiler 1928: 10, pl. 2, fig. 15.

Carcharias ( Odontaspis) cuspidata (Agassiz) — Zbyszewski & Almeida 1950: 316, pl. 1, figs 6, 7.

Carcharias ( Odontaspis) taurus Rafinesque— Zbyszewski & Almeida 1950: 318 , pl. 1, figs 12–30.

Odontaspis taurus ( Rafinesque, 1810) — Antunes & Jonet 1970: 133, pl. 4, figs 5, 6,?7, 8–11.

Odontaspis acutissima Agassiz, 1844 — Cappetta 1970: 29, pl. 1, figs 1–22, pl. 2, figs 1–16.

Lamna (Odontaspis) denticulata Agassiz, 1844 — Müller 1983: 58, pl. 12, figs 12–25, 33–34.

Synodontaspis cuspidata (Agassiz, 1844) — Freess 1992: 202, pl. 1, figs 1L, M, N.

Carcharias acutissimus Agassiz, 1844 [ sic]— Balbino 1995: 49, pl. 4, figs 1–5, pl. 5, figs 1–5.

Carcharias cuspidata Agassiz, 1843 [ sic]— Balbino 1995: 51, pl. 5, fig. 6.

Carcharias cuspidatus [ sic] Agassiz, 1843 [ sic]— Müller 1999: 36, pl. 2, figs 20–27.

Carcharias acutissima Agassiz, 1844 — Antunes & Balbino 2003: 142, pl. 1, figs 1–5, pl. 2, figs 1–5.

Carcharias cuspidata Agassiz, 1843 [ sic]— Antunes & Balbino 2003: 142, pl. 2, fig. 6.

Araloselachus cuspidatus ( Agassiz, 1843) — Cappetta 2012: 191, figs 180a–n.

Carcharias cuspidatus [ sic] Agassiz, 1843 [ sic]— Schultz 2013: 61, pl. 5, figs 5a, b, 6a, b ( cum syn.).

Carcharias acutissima Agassiz, 1843 [ sic]— Fialho 2015: 27, pl. 1, fig. 5.

Carcharias acutissimus ( Agassiz, 1843) — Fialho et al. 2021: 6, figs 3j, k.

Carcharias cuspidata (Agassiz, 1844) — Hovestadt 2020: 233, pl. 6, figs 1–6, pl. 7, figs 1–53.

Material. 267 isolated teeth and tooth parts. NHMW 2025 /0177/0012 ( 5 specimens) .

Description. The first upper anterior tooth ( Pl. 2, fig. 1) has an upright narrow and elongated principal cusp that is slightly distally oblique and five times as high as its base width. The lingual surface is strongly convex and bears a non-enameloid basal band. The mesial cutting edge is convex, and the distal one is slightly sigmoid. A well-developed cusplet is present at each side of the principal cusp, both strongly directed towards the principal cusp. The root is divided into two root lobes by a shallow central groove that diverge at an angle of 90°. The distal lobe is slightly wider than the mesial one. The second anterior tooth ( Pl. 2, fig. 2) is strong similarity to the first, but the principal cusp is slightly more curved near the apex and both cutting edges are slightly sigmoid. The third tooth ( Pl. 2, figs 3a, b) is a lateral one with a slightly sigmoidal and slightly distally inclining principal cusp that is approximately three times as high as its base width, flanked by a well-developed cusplet at each side. The root is divided into two equally wide root lobes by a shallow central groove. The root lobes diverge at an angle of 110°. A lower parasymphyseal tooth ( Pl. 2, figs 4a–c) is significantly smaller in size and mesio-distally compressed. The labiolingually sigmoid principal cusp is high and narrow with minute, poorly developed cusplets at each side. Although their basal parts are visible the root lobes are merged. The lower anterior tooth ( Pl. 2, figs 5a–b) has a high and narrow, slightly sigmoidal principal cusp with a cusplet at each side, that are directed towards the principal cusp. The principal cusp is four times higher as its base width. The root is divided into two almost equally sized root lobes that diverge at an angle of 80°. The lower lateral tooth ( Pl. 2, figs 6a, b) possesses a slightly inclined principal cusp that is two and half times as high as its base width with two mesial and distal cusplets of which the most mesial and distal ones are poorly developed. The root is divided into two equally sized root lobes that diverge at an angle of approximately 110°.

Discussion. Many of the specimens at hand are incomplete. Considering the size of the teeth, the majority represent juvenile or adolescent specimens. Those teeth that are complete and represent adult specimens show the tooth morphology of C. cuspidatus . Miocene specimens formally assigned to C. acutissima have significantly smaller teeth and possess the typical curved upper lateral teeth, being an ontogenetic development ( Hovestadt 2020).

Distribution. Upper Oligocene to Miocene, northwestern and eastern Atlantic, including the Gulf Coastal Plain of the USA ( Cicimurri et al. 2025), from the European Atlantic Frontage down to Angola, Proto-Mediterranean, Paratethys and southwestern Indian Ocean (Capetta 1987; Müller 1999; Schultz 2013), as well as the Gulf Coastal Plain of the USA ( Cicimurri et al. 2025).

Distribution in Portugal. Lower Miocene: (Burdigalian) Lower Tagus Basin ( Zbyszewski & Almeida 1950). Middle Miocene: (Langhian-Serravallian) Lower Tagus Basin ( Zbyszewski & Almeida 1950; Antunes & Jonet 1970; Fialho 2015; Fialho et al. 2021). Upper Miocene: (Tortonian) Lower Tagus Basin ( Zbyszewski & Almeida 1950; Antunes & Jonet 1970), Algarve Basin, Cacela Fm. (this paper); (Messinian) Alvalade Basin, Esbarrondadoiro Fm. ( Balbino 1995; Antunes & Balbino 2003).

Figures

FIGURE 1. Location of thestudy site, Leixão dosAlhos,Oura region,Albufeira municipality,southern Portugal, thegeographical coordinates: 37° 4'58.60"N, 8°14'0.39"W. H—Location of the Auramar Beach Resort Hotel.

FIGURE 2. Sampling site at Leixão dos Alhos, Oura region, Albufeira municipality, Algarve, Southern Portugal. X—Marks the spot shown in the Fig. 3.

FIGURE 3. Fossil shark and ray teeth on the surface of the fine sand bed at the sampling site at Leixão dos Alhos, Oura region, Albufeira municipality, Algarve, Southern Portugal (see Fig. 2). 1—Carcharhinus cf. brevipinna; 2—Myliobatiformes indet.; 3—Carcharias cuspidatus; Pb—Very rounded mainly quartz pebbles.

FIGURE 4. Taxa identified in the search sample assemblage with their absolute and relative abundances within the sample. Taxa in bold, together, represent 66.9% of the assemblage. Specimens in the search sample: 2260. Total number of specimens examined (search + bulk sample): 2579.

FIGURE 5. Taxa identified in the bulk sample assemblage with their absolute and relative abundances within the sample. Out of a total of 431 chondrichthyan remains collected, 319 were identified.Taxa in bold, together, represent 55.5% of the assemblage. They are the most representative ones for palaeoecological interpretation as, presumably, they were the most abundant species in the chondrichthyan coastal fauna of this region of southwestern Iberia during the Late Miocene Tortonian. Specimens identified in the bulk sample: 319. Total number of specimens examined (search + bulk sample): 2579.

FIGURE 6. Estimation of palaeobathymetry based on the most common species (shaded area). Taxa in bold italics, to the left, are those represented in the study assemblage, now extinct. Species in normal italics are present day equivalents. B—Ranking of the species in the bulk sample (Fig. 5). S—Ranking of the species in the search sample (Fig. 4). Together, these species represent approximately 65% (1689 out of 2579) of the specimens in the study assemblage. The depth range of living representatives, at specific or generic level, was gathered from Compagno (1984), Vialle et al. (2011), Ebert et al. (2021), and online data available at www.fishbase.org of Froese & Pauly (2019).