Systematics

This species was originally described in 1875 (11 Salvadori, T. (1875). Descrizione di cinquantotto nuove specie di uccelli, ed osservazioni intorno ad altre poco note, della Nuova Guinea e di altre Isole Papuane, raccolte dal Dr. Odoardo Beccari e dai cacciatori del Sig. A. A. Bruijn. Annali del Museo Civico di Storia Naturale di Genova 7:896–976. Close ), and subspecies Zosterops fuscicapilla crookshanki was described in 1935 (9 Mayr, E., and A. L. Rand (1935). Results of the Archbold Expeditions. 6. Twenty four apparently undescribed birds from New Guinea and the D’Entrecasteaux Archipelago. American Museum Novitates 814:1–17. Close ) based on specimens from Goodenough Island. This subspecies has been granted full species status in the past, based mainly on differences in eye-ring size, iris coloration, body size, and a seemingly very different song (4 Pratt, T. K., and B. M. Beehler (2015) Birds of New Guinea. Second edition. Princeton University Press, Princeton, New Jersey, USA. Close , 9 Mayr, E., and A. L. Rand (1935). Results of the Archbold Expeditions. 6. Twenty four apparently undescribed birds from New Guinea and the D’Entrecasteaux Archipelago. American Museum Novitates 814:1–17. Close ). Some authors consider that a population of this species that was discovered on Fergusson Island belongs to Zosterops fuscicapilla crookshanki and therefore reinforces the case for species rank for this subspecies (4 Pratt, T. K., and B. M. Beehler (2015) Birds of New Guinea. Second edition. Princeton University Press, Princeton, New Jersey, USA. Close ). However, birds from Fergusson Island also share traits with the nominate subspecies, like the black crown and head sides, unlike birds from Goodenough Island. Thus, birds from Fergusson Island could represent an intermediate form between nominate and Zosterops fuscicapilla crookshanki, or may represent an undescribed subspecies.

The present species has also been treated as conspecific with Black-headed White-eye (Zosterops hypoxanthus), to which subspecies fuscicapilla is very similar.

Zosterops fuscicapilla crookshanki males have olive-colored head with black loral area (Goodenough Island) or black extending from forehead and lores to crown and head-sides (Fergusson Island), in both cases with a prominent broad white eye-ring; upperparts yellowish olive-green, rump olivaceous, upperwing-coverts and tertials with paler and brighter greenish edgings, outer remiges and tail dull brownish; throat and underparts rather dull yellowish olive; iris silver-gray; bill dark gray to blackish, mandible with base lighter gray; legs gray. The female is similar, perhaps somewhat duller than male.

Previous authors (12 del Hoyo, J., and N. J. Collar (2016). HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions, Barcelona, Spain. Close ), employing a quantitative criteria for species delimitation (13 Tobias, J. A., N. Seddon, C. N. Spottiswoode, J. D. Pilgrim, L. D. C. Fishpool, and N. J. Collar (2010). Quantitative criteria for species delimitation. Ibis 152(4):724–746. Close , 14 Tobias, J. A., P. F. Donald, R. W. Martin, S. H. M. Butchart, and N. J. Collar (2021). Performance of a points-based scoring system for assessing species limits in birds. Ornithology 138:1–14. Close ) (from which scores in brackets are derived), treated Zosterops fuscicapilla crookshanki as a full species based on its markedly broader eye-ring [2]; silver-gray vs brown iris [3, assuming that iris color is pale on Goodenough Island]; less yellow, more olivaceous on rump and underparts [1]; browner tail (ns[1]); larger size [at least 1]; and seemingly very different song on basis of published descriptions (9 Mayr, E., and A. L. Rand (1935). Results of the Archbold Expeditions. 6. Twenty four apparently undescribed birds from New Guinea and the D’Entrecasteaux Archipelago. American Museum Novitates 814:1–17. Close , 4 Pratt, T. K., and B. M. Beehler (2015) Birds of New Guinea. Second edition. Princeton University Press, Princeton, New Jersey, USA. Close ).

Based on a study analyzing the phylogenetic relationships of the numerous species in this genus using many genetic markers, the sister species of Zosterops fuscicapilla is New Guinea White-eye (Zosterops novaeguineae). The affinities with other Australasian Zosterops are not clear (15 Oliveros, C. H., M. J. Andersen, and R. G. Moyle (2021). A phylogeny of white-eyes based on ultraconserved elements. Molecular Phylogenetics and Evolution 164:107273. Close ).

Also called Western Mountain or Yellow-bellied Mountain White-eye (16 Beehler, B. M., and T. K. Pratt (2016). Birds of New Guinea: Distribution, Taxonomy, and Systematics. Princeton University Press, Princeton, NJ, USA. Close ). In Hewa, a Sepik language of northern Papua New Guinea, white-eyes are collectively referred to as Yenuk (17 Thomas, W. H. (1999). Traditional environmental knowledge and its implications for modern conservation among the Hewa of Papua New Guinea. PhD thesis, Arizona State University, Arizona, USA. Close ).

Oya Tabu White-eye is commonly used for subspecies Zosterops fuscicapilla crookshanki, especially when considered a separate species.

No information available.