Tyto cravesae Suárez & Olson, 2015, new species
Creators: name: Suárez, William
name: Olson, Storrs L.
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Aves
Strigiformes
Tytonidae
Tyto
Tyto cravesae

description: Tyto cravesae, new species
Craves’s Giant Barn Owl; Lechuza Gigante de Craves (Figs. 2 D; 3A,C; 4C,D,E,G; 5E,F; 6B,C,G,H; 7D,E; 8A)
Holotype. Associated postcranial elements of a single individual MNHNCu 75. 590 (original numbers in collection of William Suárez are indicated in parentheses), consisting of the proximal half of a left humerus (WS 1026E″), proximal end of a right ulna (WS 1114E″), nearly complete right carpometacarpus (WS 1027E″), and a nearly complete right femur (WS 1025E″). Collected by William Suárez on 5 June 1998.
Type locality and age. Cueva de Paredones, about 3 km SW of Ceiba del Agua, Municipality of Caimito, Artemisa (formerly La Habana) Province, Cuba (see Arredondo 1961, 1970, 1971, 1982, 1984; Brodkorb 1969; Morgan & Ottenwalder 1993; Gutiérrez 2010). The type material was collected within the cave and near the place known as “Salón del Pozo” (see Morgan & Ottenwalder 1993), in an amoeboid-shaped patch of red clay matrix (ca. 50 cm in its greatest diameter) in a wall cavity about 1.5 m from the floor of the cave. Quaternary, probably late Pleistocene but not dated (see Morgan & Ottenwalder 1993 for discussion of the age of deposits in Cueva de Paredones). This is the type locality of other Cuban fossil birds such as Pulsatrix arredondoi Brodkorb, Gymnogyps varonai (Arredondo), Ornimegalonyx “ minor ” Arredondo, and Oscaravis olsoni (Arredondo & Arredondo) (see Brodkorb 1969; Arredondo 1971, 1976, 1982, 1984; Arredondo & Arredondo 2002b, Suárez & Olson 2009).
Measurements (mm) of holotype. Humerus: proximal width 22.5, depth of head 6.2, width of shaft at level of distal end of deltopectoral crest 9.7, depth of shaft at level of distal end of deltopectoral crest 9.3, depth of midshaft 8.8. Ulna: proximal depth 13.7. Carpometacarpus: length 70.0, proximal width 7.2, proximal depth 15.3. Femur: length through internal condyle 79.5+ (abraded), proximal width 15.5, proximal depth 9.7, shaft width at midpoint 6.8, shaft depth at midpoint 7.9, depth of internal condyle 10.8.
Paratypes. Topotypes. — Coracoid: sternal end of left (OA 832). Humerus: shaft of left (WS 077). Tibiotarsus: distal end of left (OA 831, paratype of T. noeli). Tarsometatarsus: complete right (MNHNCu 75.596), right lacking distal end (OA 828, paratype of T. noeli), proximal end of right (MNHNCu 75.595, juvenile, formerly WS unnumbered), distal end of right (WS 09I, juvenile).
Cueva del Campo de Tíro, Meseta de Anafe, Municipality of Caimito, Artemisa (formerly La Habana) Province, Cuba. — Femur: left lacking a proximal portion of the shaft (MNHNCu 75.594, formerly WS 218E).
Cueva del Túnel, La Salud, Municipality of Quivicán, Mayabeque (formerly La Habana) Province, Cuba. — Humerus: proximal end of right (OA 826, paratype of T. noeli), distal half of right (OA 804, paratype of T. noeli). Tibiotarsus: distal half of left (MNHNCu 75.593, formerly WS 216). Tarsometatarsus: distal end of left (MNHNCu 75.591, formerly WS 137), distal end of right (MNHNCu 75.592, formerly WS 215).
Cuevas Blancas, Aguacate, Municipality of Quivicán, Mayabeque (formerly La Habana) Province, Cuba. — Femur: Proximal end of left (CZACC unnumbered). Tarsometatarsus: shaft of right (CZACC unnumbered).
Las Breas de San Felipe, Martí, Municipality of Martí, Matanzas Province, Cuba. — Tarsometatarsus: distal end of left (MNHNCu 75.4801) (see Iturralde-Vinent et al 2000).
Measurements of paratypes. See Table 1–2.
Distribution. Fossil localities in Western Cuba, from Artemisa to Matanzas Provinces.
Etymology. After Julie Craves, of the University of Michigan-Dearborn, for her dedication to avian conservation and her boundless appreciation of Cuban friends and birds.
Diagnosis. A species of the genus Tyto that is larger than T. noeli and smaller than T. pollens, about the size of some specimens of T. ostologa but less robust, differing from that species by the longer carpometacarpus, deeper and more ovoid shaft of the femur, tarsometatarsus distinctly flared at the ends, and fossa parahypotarsalis medialis smaller.
Description and comparisons. Specimens referred to Tyto cravesae are consistently larger and more robust than the equivalent elements in the skeleton of T. noeli, and smaller and much more gracile than those of T. pollens. Juvenile specimens of T. cravesae are also consistently larger and more robust than juveniles or adults of T. noeli (Fig. 6). Qualitative characters in comparison with T. noeli include: femur with a much deeper shaft (Fig.4), being ovoid in cross section (cylindrical or less ovoid with much less deep shaft in T. noeli); distal end with posterior articular surface of the internal condyle larger and more expanded (smaller in T. noeli); distal end of tibiotarsus (Fig.5) with shaft greatly expanded bilaterally and with the tendinal groove wider (shaft not expanded, tendinal groove thinner in T. noeli); tarsometatarsus (Figs.6–8) with shaft relatively shorter but more robust, with anterior metatarsal groove expanded and relatively shallow (shaft relatively longer and thinner, with anterior metatarsal groove thinner and deeper in T. noeli), tubercle for tibialis anticus distally placed (this character can be variable) being separated from the proximal metatarsal foramina (consistently proximad and closer to proximal metatarsal foramina in T. noeli), distal end proportionately less massive (in some individuals) than in T. noeli.
Bones of T. cravesae are less robust, but similar in linear dimensions to some specimens of T. ostologa (Figs. 3, 4, 7, 8; Table 1–2). Most of the pectoral elements of T. cravesae, including coracoid, humerus, and ulna, are very similar in characters when compared with T. ostologa; in contrast, the carpometacarpus and hindlimb elements show consistent diagnostic characters including carpometacarpus (Fig. 3; Table 1) longer with a more slender metacarpal II (shorter and more robust metacarpal II in T. ostologa); femur (Fig. 4, Table 2) with the shaft more ovoid in cross section, so that it is much wider in either lateral or medial view (shaft more cylindrical, less ovoid in T. ostologa); tarsometatarsus (Figs. 6–8, Table 2) with proximal half of shaft relatively more expanded or wider, flaring more gradually proximad (shaft less expanded, flaring more abruptly at the proximal articulation in T. ostologa), anterior metatarsal groove also relatively wider (narrower in T. ostologa), fossa parahypotarsalis medialis smaller (internal view), resulting the medial (inner) border of shaft at this level wider (usually larger, greatly expanded and with thin medial border in T. ostologa), distal end less developed and smaller (much more developed, larger and massive in T. ostologa).
Compared with T. pollens, the femur of T. cravesae has the shaft deeper and ovoid (less deep or ovoid in T. pollens); tarsometatarsus relatively more elongated with the shaft less constricted bilaterally at midpoint (very wide and robust, relatively shorter, greatly constricted shaft bilaterally at midpoint in T. pollens). Other comparable elements of these two species are very similar in qualitative characters, being distinguishable mostly by the discrepancies in size and robustness mentioned above, T. pollens being the largest (Tables 1–2).
Remarks. The species Tyto cravesae seems to be more closely related to T. noeli than to T. ostologa of Hispaniola, which is different in the morphology of the carpometacarpus and proximal end of the tarsometatarsus. Tyto cravesae is, after T. pollens (including T. riveroi), the rarest species of barn owl in the fossil record of Cuba. A deposit formed from ancient pellets of this new species was discovered and excavated by WS in January of 1992, in a cave named Cueva del Campo de Tíro, in the eastern extremity of Meseta de Anafe, near Cayaguasal, Caimito. This deposit was located in a small depression about one meter in diameter and 9 cm at its deepest point, embedded in a dry red-orange soil (see Paratypes of T. cravesae). The deposit was filled with fragmentary material, including bones of juveniles of the extant rodent Capromys pilorides (Say) and juveniles and adults of the extinct Geocapromys columbianus (Chapman), plus scarce remains of Tyto cravesae (W. Suárez unpubl. data). The existence in Cuba of large members of Tyto such as T. cravesae and strigid owls of about the same size and larger (Arredondo 1976, 1982, 1984; Arredondo & Olson 1994) probably contributed to the rarity of T. pollens there in the late Pleistocene, but just how the almost staggering diversity of avian raptors may have partitioned their potential resources of prey remains to be explored.
description: Published as part of Suárez, William & Olson, Storrs L., 2015, Systematics and distribution of the giant fossil barn owls of the West Indies (Aves: Strigiformes: Tytonidae), pp. 533-553 in Zootaxa 4020 (3) on pages 545-548, DOI: 10.11646/zootaxa.4020.3.7, http://zenodo.org/record/240356