Fregilupus Lesson, 1831

Hume, Julian Pender, 2014, Systematics, morphology, and ecological history of the Mascarene starlings (Aves: Sturnidae) with the description of a new genus and species from Mauritius, Zootaxa 3849 (1), pp. 1-75 : 8-10

Genus Fregilupus Lesson, 1831 .

Fregilupus Lesson, 1831 , p.324. Type (by monotypy): Upupa capensis Gmelin = Upupa varia Boddaert. Lophopsarus Sundeval, 1872 , p.40. Type: Upupa varia Boddaert.

Etymology. A composite word from the old genus Fregilus Cuvier, 1817 , chough (now Pyrrhocorax ), and Upupa Linnaeus, 1758 , hoopoe), from the curved bill of the Réunion crested starling, which by early settlers on the island was called Huppe (hoopoe) from its crest and stout curved bill.

Revised Diagnosis. Only the relevant skeletal elements of Fregilupus are described here. For further descriptions of cranial and post-cranial material, see Murie (1874), Milne-Edwards & Oustalet (1893), Berger (1957), Bock (1962) and Morioka (1996). Fregilupus is distinguished from other Mascarene sturnids by the following characters:

Cranium: in dorsal view, rounded, somewhat bulbous posteriorly; frontal narrow; in posterior view, crista nuchalis transversa rounded with distinct prominentia cerebellaris; foramen magnum large; in lateral view, foramen. n. optici small, almost equal in size to fonticuli orbitocraniales; processus postorbitalis elongate.

Rostrum: long and narrow with narrow, oval-shaped narial openings; rostrum maxillare narrow and strongly decurved.

Mandible: rostrum mandibulae narrow and sharply pointed; processus mandibulae medialis small; processus retroarticularis distinct; single large fenestra rostralis mandibulae.

Sternum: short and wide, particularly at caudal end; processus craniolateralis long and blade-like; spina externa bifurcated, projections narrow; in lateral view, apex carinae reduced; carina sterni shallow; in dorsal view, trabecula intermedia the same distal extent as margo caudalis; fenestra medialis reduced.

Coracoid: comparatively reduced in total length; shaft robust.

Humerus: robust with straight shaft; proximal and distal ends cranio-caudally flattened; tuberculum ventrale reduced; two pneumatic fossae; pneumatic fossa II completely enclosed and separated from pneumatic fossa I by medial bar; small circular depression on proximal side of tuberculum ventrale; processus supracondylaris dorsalis small with little proximad extension; crista deltopectoralis reduced, shallow in dorsal view.

Radius: robust; facies articularis radiocarpalis distinctly indented.

Ulna : impressio brachialis reduced.

Carpometacarpus: processus extensorius blunt.

Pelvis: extremely robust; ala preacetabularis ilii narrow; ala ischii broad; fenestra ischiopubica large and ovalshaped.

Femur: robust, particularly at proximal and distal ends; shaft straight with little expansion proximad and distad of mid-length; sulcus intercondylaris deeply excavated; facies articularis acetabularis large; in cranial aspect, sulcus patellaris indistinct proximal to condyles.

Tibiotarsus: long and robust; shaft broad and expanded, particularly near distal end; tuberculum retinaculi m. fibularis indistinct; crista cnemialis cranialis broad and expanded; impressio ligamenti collateralis medialis deep emphasising a ridge distal to crista cnemialis cranialis.

Tarsometatarsus: long and robust; shaft comparatively straight; trochleae not expanded lateromedially; impressio retinaculi extensorii with small bridge; crista medialis hypotarsi large and expended distad; foramen vasculare distale large and distinct; in dorsal aspect, distinct proximal ridge on facies dorsalis; proximal extension of fossa metatarsi I lacking medial ridge; in plantar view, trochlea metatarsi III distinctly larger than trochlea metatarsi II; fossa parahypotarsalis medialis not situated in deep groove.

Remarks. There has been considerable confusion over the affinities and provenance of Fregilupus . The first account supposedly to mention the bird was penned by Flacourt (1658: 166) in his list of birds of Madagascar, where he described a bird called the Tivouch (Tiuouch) . He merely stated: “ Tivouch is the hoopoe, it is speckled black and grey, and has a beautiful feathered crest (my translation)." Newton (in Murie 1874) doubted that this was referable to Fregilupus , and considered it to be a description of a true Upupa , the Madagascar Hoopoe Upupa epops marginata , which is barely distinct from the Eurasian nominate, Upupa e. epops . Fregilupus was also called the Huppe (=Hoopoe) by the local inhabitants of Réunion, due to its morphological similarities with the Eurasian hoopoe (long, decurved bill and crest). That Fregilupus was thought to occur in the Cape and Madagascar is based in part on mistakes by De Montbeillard (in Buffon 1779: 463) and Levaillant (1807: 43), who both believed that the Tivouch was referable to Fregilupus . This erroneous provenance was followed by all subsequent authors, until Vinson (1868: 627) asserted that Fregilupus was restricted to Réunion. Therefore, as a result of this misidentification, Fregilupus varius was placed in Upupa by a number of authorities. However, it was also variously placed amongst birds of paradise and bee-eaters ( Levaillant 1807: 43), choughs ( Vieillot 1817: 3; Lesson 1831: 324), cow-birds or Pastors ( Wagler 1827: 90) and Icteridae ( Gray 1870: 28) .

Although Fregilupus had been long considered a member of Upupidae , it differs markedly in osteology from Upupa epops . The latter species differs from Fregilupus by the following key diagnostic characters and also in morphometrics (see appendix 1):

Cranium: in dorsal view, less bulbous posteriorly; frontal wide; in posterior view, crista nuchalis transversa small with less distinct prominentia cerebellaris; in lateral view, foramen. n. optici extremely reduced compared with large fonticuli orbitocraniales.

Rostrum: extremely long and narrow, about 2.5 times cranium length, with very small narial openings; rostrum maxillare narrow and strongly decurved.

Mandible: rostrum mandibulae long and narrow; processus retroarticularis lacks medial projections; single reduced fenestra rostralis mandibulae.

Sternum: short and narrow, particularly at caudal end; spina externa not bifurcated; in lateral view, apex carinae rounded, not projecting beyond spina externa; carina sterni deep; in dorsal view, trabecula intermedia shorter than margo caudalis.

Coracoid: processus lateralis extends further laterally; sulcus m. supracoracoidei enclosed with a bony bridge.

Scapula: short and straight.

Humerus: robust with curved shaft; processus supracondylaris dorsalis small with little proximad extension; crista deltopectoralis distinctly triangular and extends further distad; fossa pneumotricipitalis indistinct; processus supracondylaris dorsalis lacks proximal projection; caput humeri reduced.

Radius: distinct tuberculum bicipitale radialis.

Ulna : more pronounced extension of olecranon.

Carpometacarpus: os metacarpale minus extends further distally from os metacarpale majus; processus extensorius sharply pointed, not rounded.

Pelvis: less robust; ala preacetabularis ilii and ala postacetabularis ilii narrow; more numerous foramina intertransversaria.

Femur: comparatively robust, with thick shaft and little expansion at distal end; sulcus intercondylaris shallow; facies articularis acetabularis reduced.

Tibiotarsus: short and straight; greatly expanded distal end; shaft broad and expanded, particularly proximal to distal end; crista cnemialis cranialis not extended laterally into a hook; pons supratendineus absent.

Tarsometatarsus: short and gracile; trochleae metatarsi II expanded mediad; impressio retinaculi extensorii without bridge; crista medialis hypotarsi large and expanded distad; single enclosed sulcus hypotarsi.

Schlegel (1857: 338), albeit briefly, was the first person to suggest the sturnid affinities of Fregilupus , followed by Hartlaub (1861: 53), who made a detailed study of the skin and placed it alongside the monotypic Madagascar starling genus, Hartlaubius (now Saroglossa ). Based on this evidence, Sundeval (1872: 40) proposed the generic name Lophopsarus (=crested starling), but according to the rules of the International Commission on Zoological Nomenclature (1999), this more appropriate name remains a junior synonym of Fregilupus .

Murie (1874) made a detailed anatomical study of the only known skeleton of Fregilupus held at the UMZC, which confirmed its sturnid affinities. There were originally two spirit specimens of Fregilupus deposited at the MNHN by the natural historian, Julien Desjardins (see below); one was exchanged with the MCZH, and the other was exchanged with the AMNH ( Jouanin 1962). Miller (1941) partly dissected the MCZH Fregilupus spirit specimen, and based on the comparative study of the pelvic and pectoral girdles and the syrinx, concluded that it differed little from Eurasian Starling Sturnus vulgaris . Despite the earlier conclusions, Amadon (1943) had reservations about the relationships of Fregilupus , suggesting that it might belong to Vangidae , but that more data were needed. He disregarded this view after examining skin specimens, and considered it to be a starling, noting morphological similarities with SE Asian Sturnus ( Amadon 1956) . Berger (1957) dissected the AMNH spirit specimen and cast some doubt on a sturnid relationship, although he provided little evidence in support of an alternative. He further remarked on suggestions made by Amadon and Ernst Mayr therein, that there might be a possible relationship with prionopid shrikes ( Prionopidae ), so it appears that Amadon was still uncertain about the relationships of Fregilupus . As Dorst (1960a, b) also proposed that Fregilupus might be related to vangas, Morioka (1996) compared cranial osteology with the Sickle-billed Vanga Falculea palliata and concluded that there was no direct relationship. MtDNA analysis has since confirmed that the affinities of Fregilupus lie within Sturnidae and that it is distantly related to SE Asian genera ( Zuccon et al. 2008; see below).