SPECIES

Ruvu Weaver Ploceus holoxanthus Scientific name definitions

H. Dieter Oschadleus
Version: 1.0 — Published October 25, 2022

Systematics

Systematics History

Ploceus holoxanthus Hartlaub, 1891, Abhandlungen der Naturwissenschaftlichen Vereins zu Bremen 12:22. — Mtoni [near Bagamoyo, eastern Tanganyika].

The holotype is an adult male, collected in January (7) or March (4) 1890 by Friedrich Bohndorff, and held at the American Museum of Natural History (AMNH 724738) (7). January is probably correct for the holotype and female, while March may refer to the additional specimens that Shelley examined.

Description History

The Ruvu Weaver was described by Karel Johan Gustav Hartlaub in 1891, based on two specimens collected by Friedrich Bohndorff, from Mtoni on the Kingani (now Ruvu) River, Tanzania (3). Most authors accepted this new species initially, but in 1916, Zedlitz (8) wrote an extensive review of several golden weavers, claiming that Ruvu Weaver was not distinguishable from the African Golden-Weaver (Ploceus subaureus). At this time no one (including Zedlitz) realized that they had not seen the actual Ruvu Weaver specimens, but instead were looking at African Golden-Weaver specimens (1). Thereafter, other authors followed Zedlitz in keeping Ruvu Weaver as a synonym of African Golden-Weaver. The Ruvu and Yellow Weavers are very similar in plumage, and in specimens the distinctly different eye colors of males is not apparent.

After describing the Ruvu Weaver, Hartlaub sent the specimens to Tring (before 1905 when Shelley studied them; 4). In 1934 most of Rothschild's collection at Tring was sold to the American Museum of Natural History in New York, where the Ruvu Weaver specimens are still housed (7). Shelley (4) had noted that there were four specimens, but LeCroy (7) only listed two, the holotype and a female; Shelley’s two additional specimens were either lost, or are still in a museum somewhere, or were misidentified (but this is less likely because of his detailed description). The missing specimens are not in the Bremen Museum collection, where many of Hartlaub's other type specimens are (9).

From 2003, birds resembling the Ruvu Weaver have been seen and photographed increasingly. Thus, samples of Ruvu Weaver were included in a genetic study on the Ploceidae (10), which showed that it is a valid species, and not closely related to African Golden-Weaver, in spite of a close plumage resemblance. Fjeldså et al. (10) placed Ruvu Weaver in the genus Textor.

Geographic Variation

Ruvu Weaver has a limited global range, and no geographic variation is known.

Subspecies

Monotypic

Related Species

In a phylogenetic study using multiple genetic markers, Ruvu Weaver was found to be very closely related to Southern Brown-throated Weaver (Ploceus xanthopterus) and Kilombero Weaver (Ploceus burnieri), though relationships among these three species was not resolved (10). The males of these recently diverged weaver species are bright yellow with varying amounts of orange or brown on the face, and the females all have a two-colored bill (1). It appears that these three species were part of a clade that also included Golden Palm Weaver (Ploceus bojeri), Taveta Golden-Weaver (Ploceus castaneiceps), and Black-headed Weaver (Ploceus melanocephalus), among several others (10). Further work is needed to fully resolve the relationships among all of these species.

Nomenclature

In his description of this species, Hartlaub noted it was the yellowest of all weavers, thus giving a Greek name meaning "entirely yellow," holoxanthus, with holos meaning complete or entire, and xanthos, meaning yellow (3).

Recommended Citation

Oschadleus, H. D. (2022). Ruvu Weaver (Ploceus holoxanthus), version 1.0. In Birds of the World (S. M. Billerman and N. D. Sly, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.ruvwea1.01