Systematic Palaeontology - 5
Genus Buteogallus Lesson
†Buteogallus borrasi (Arredondo, 1970)
Referred material. San Felipe I: Distal end of right tibiotarsus, MNHNCu 75.4678; distal ends of left tibiotarsi, MNHNCu 75.4665, MNHNCu 75.4693; left tarsometatarsus without trochleae, MNHNCu 75.4666; left tarsometatarsus lacking proximal articular region and trochleae metatarsorum II and III, MNHNCu 75.4667; proximal half of left tarsometatarsus without inner calcaneal ridge of the hypotarsus, MNHNCu 75.4686; proximal end of left tarsometatarsus without calcaneal ridges of the hypotarsus, MNHNCu 75.4692; distal halves of left tarsometatarsi, MNHNCu 75.4687-4688; fragmentary distal end of left tarsometatarsus, MNHNCu 75.4691; proximal end of right tarsometatarsus without inner calcaneal ridge of the hypotarsus, MNHNCu 75.4677; proximal segment of shaft of a right tarsometatarsus, MNHNCu 75.4669; distal end of right tarsometatarsus, MNHNCu 75.4670; distal ends of right tarsometatarsi without trochlea metatarsi III, MNHNCu 75.4689-4690; distal shaft of right tarsometatarsus, MNHNCu 75.4668; left metatarsal I, MNHNCu 75.4694; right metatarsal I, MNHNCu 75.4682; phalanx 1, left digit I, MNHNCu 75.4697; phalanx 1 without distal end, left digit I, MNHNCu 75.4671; phalanges 1, right digits I, MNHNCu 75.4695-4696; ungual phalanges, left digits I, MNHNCu 75.4672, 75.4684-4685; ungual phalanx, right digit I, MNHNCu 75.4683; ungual phalanges, left digits II, MNHNCu 75.4679-4680; ungual phalanges, right digits II, MNHNCu 75.4673-4676; ungual left, MNHNCu 75.4681, and right, MNHNCu 75.4707, phalanges of digit III.
Description. General morphology as in Buteogallus urubitinga (Gmelin, 1788), but about a 33% larger. For a more detailed description see Suárez (2004a), and Suárez & Olson (2007, 2009b).
Measurements. See Suárez & Olson (2007: tables 1–4); Table 6.
Comments. Buteogallus borrasi (Arredondo, 1970) was recorded for this locality by Iturralde-Vinent et al. (2000), and the material under study was described by Suárez & Olson (2007, 2009b). This is the most common accipitrid found in Quaternary deposits along the Cuban archipelago (Suárez 2004a:124; Suárez & Olson 2007: 296), and also in Las Breas de San Felipe. Wetmore (1928: 3–4, figs. 1–2), recorded Geranoaetus melanoleucus (Vieillot, 1819) for Cuba, on the basis of an incomplete left carpometacarpus (AMNH 6190)—plus an ungual phalanx without catalog number—from the thermal baths of Ciego Montero, Palmira Municipality, Cienfuegos Province, noting that it “is exactly similar to Geranoaëtus [sic.] melanoleucus and is identified as that species”. Given the carpometacarpus of B. borrasi is about the size of (G. melanoleucus in square brackets: Proximal width, 8.3–8.4 (8.3) 2 [7.3–8.5 (7.7) 8]; proximal depth, 21.1–22.1 (21.6) 2 [17.8–21.8 (20.1) 8]; depth of metacarpal II at midpoint, 5.7 [4.9–5.6 (5.1) 4].) and very similar in characters to the same element in G. melanoleucus (Suárez unpubl. data), it seems that AMNH 6190 represents the very common Borras’ Hawk, instead of the species recorded in 1928. Unfortunately, at the present stage, the specimens in AMNH have not been located.
Buteogallus cf. †B. fragilis (L. Miller, 1911)
Referred material. San Felipe II: Distal end of right tibiotarsus, MNHNCu 75.4735; distal segment of shaft of left tarsometatarsus, MNHNCu 75.4736.
Description. Smaller when compared with Buteogallus borrasi or “Amplibuteo” woodwardi. Specimen MNHNCu 75.4735 differs from the tibiotarsus of Geranoaetus melanoleucus, and agrees with those of B. fragilis (L. Miller, 1911), in its slightly smaller size, flattened supratendinal bridge (not inflated or domed) with more horizontal orientation, less deep and wider tendinal groove, and medial condyle much more projected mediad. This specimen is identical in small details and size to tibiotarsus RLB E4091, within the series of this bone examined (N = 33). The distal fragment of tarsometatarsus MNHNCu 75.4736, differs from the equivalent element in G. melanoleucus, by having the metatarsal facet in a lower (or distad) position and being slightly smaller, also as in B. fragilis. This specimen is very similar in size and characters to RLB D3604, within the series of tarsometatarsi examined (N = 70) of the latter species. For comparisons between B. fragilis and B. borrasi, see Suárez & Olson (2007: 293).
Measurements. (RLB specimens in parenthesis). Tibiotarsus.—distal width: 15.3+ (15.3–17.8 [16.7] 27). Tarsometatarsus.— least width of shaft: 7.9 (6.4–8.4 [7.3] 33).
Comments. Comparisons with other accipitrids (see Appendix 1) and with extensive series of B. fragilis from Rancho La Brea, California, show that the two Cuban specimens are referable to this taxon. This record is the first for Cuba and the Antilles, as well as the first occurrence of the species outside the continental mainland. This raptor is probably another member of the Cuban avifauna derived from populations established in Florida, as the taxon is considered to have been present in that peninsula since the late Pliocene (Emslie 1998). Another extinct hawk, close in general character to those present in B. fragilis—see Howard (1932) for descriptions, comparisons, and discussion of characters that place “Geranoaetus” fragilis under Urubitinga (= Buteogallus)—but much smaller and not referable to the species B. gundlachii (Cabanis, 1855), B. anthracinus (Deppe, 1830), or any of the other member of the genus, is described below.
†Buteogallus royi sp. nov.
Holotype. Left tarsometatarsus, MNHNCu 75.4909. Collected in San Felipe I, C area, on May 12, 2009, by William Suárez and Stephen Díaz Franco.
Measurements (mm) of holotype. Total length: 92.9; proximal width: 13.6+; proximal depth between calcaneal ridges of hypotarsus: 5.8; proximal width at level of tubercle for tibialis anticus: 10.5; least width and depth of shaft at midpoint: 6.7–8.1; least width and depth of shaft at proximal end of metatarsal facet: 7.4–5.5; distal width: 16.1+; width and depth of trochlea metatarsi III: 4.5–6.2; width of trochlea metatarsi II: 3.4; width of trochlea metatarsi IV: 3.3 (see Table 5).
Referred material. San Felipe II: Distal third of right ulna, MNHNCu 75.4737.
Etymology. Species dedicated to the memory of Dr. Roy E. Dickerson, discoverer of Las Breas de San Felipe, and the first to report fossil bird remains in Cuban tar seeps.
Diagnosis. Species similar in size to the living Buteogallus anthracinus and B. gundlachii, but with a tarsometatarsus longer and more robust, with deep and wide anterior metatarsal groove and tubercle for tibialis anticus located more proximad.
Description. Buteogallus royi sp. nov. differs from the extinct hawks B. fragilis, B. daguetti (L. Miller, 1911), B. terrestris (Campbell, 1979) and B. borrasi, as well as the living species B. solitarius (von Tschudi, 1844), B. coronatus (Vieillot, 1817), B. meridionalis (Latham, 1790) and B. urubitinga, due to its smaller size (Table 5). The tarsometatarsus present in B. aequinoctialis (Gmelin, 1788) is smaller. MNHNCu 75.4909 is comparable in size only to those of B. anthracinus and B. gundlachii (for size correlation of these living taxa see Olson 2006), but differs from these species by having the following combination of characters (Fig. 9–10A–C): shaft elongated and columnar (elongated but more gracile in B. anthracinus; consistently shorter and more gracile in B. gundlachii), reduced proximal end that is flaring bilaterally from a more proximal point on shaft (expanded, flaring gradually from a more distal point on shaft in B. anthracinus and B. gundlachii), broad and deep fossa infracotylaris dorsalis (reduced and less excavated in B. anthracinus and B. gundlachii), deep anterior metatarsal groove, very excavated and wide (less excavated and narrower in B. anthracinus and B. gundlachii), tubercle for tibialis anticus located proximad and laterad (distad and medially located in B. anthracinus and B. gundlachii), poorly developed internal metatarsal border (more developed and less flattened in B. anthracinus and B. gundlachii), trochlea metatarsi II more projected mediodistad (less projected in B. gundlachii; moderately projected in B. anthracinus), inner calcaneal ridge of the hypotarsus with base short, only slightly extended distally, and truncated by the medial proximal foramen (similar in some specimens of B. anthracinus; usually more distally extended in B. gundlachii), deep posterior metatarsal groove (less deep in B. anthracinus and B. gundlachii), metatarsal facet less expanded mediad (more medially expanded in B. anthracinus and B. gundlachii), and well developed crista plantaris lateralis (less developed in B. anthracinus and B. gundlachii).
Comments. The Roy’s Hawk, as the other extinct Buteogallus species present in this deposit, was a larger bird when compare with B. gundlachii, the only living species of the genus in Cuba (Wiley & Garrido 2005), which is common in mangroves, coastal swamps of the main island, Isla de la Juventud, and keys (Garrido & Kirkconnell 2011:79). The tarsometatarsus of B. royi sp. nov. is very different from that of B. anthracinus and B. gundlachii, being more similar to B. fragilis in some of its characters (see comparisons and description above; Fig. 9C). The latter species (and the new Cuban taxon described herein), is not referable to genera Buteo Lacépède, Rupornis Kaup, Parabuteo Ridgway, Geranoaetus, or Spizaetus Vieillot either, being similar in most of the characters to Buteogallus, in which it has been accommodated by Howard (1932), and where I maintain both species. The distal fragment of ulna (Fig. 10D–E), tentatively referred to B. royi sp. nov., is also similar in size and general characters to both B. anthracinus and B. gundlachii.
Figure 10. Buteogallus royi sp. nov.: Left tarsometatarsus (Holotype, MNHNCu 75.4909) in anterior (A), medial (B) and posterior (C) views; right ulna (MNHNCu 75.4737) in dorsal (D) and ventral (E) views. Buteo sanfelipensis sp. nov.: Left tarsometatarsus (Holotype, MNHNCu 75.4910) in anterior (F), medial (G) and posterior (H) views. Scale = 2 cm.