Family Eulacestomatidae, familia nova ―ploughbills

Type genus: Eulacestoma De Vis, 1894

Diagnosis. Small, short-tailed, bull-headed songbirds with olive-citrine plumage; sexes dimorphic, males blackbreasted and -winged with large, flat, circular gape wattles, females plain-plumaged, intrinsically dimorphic in rufous- and olive-winged plumages (possibly age-related) and unwattled; juveniles flushed rufous on wings and sides of breast; head broad, the bill much compressed bilaterally and as deep as long, tomia smooth except for terminal maxillary notch, and narial depression rounded, with inoperculate, holorhinal and internally pervious nostrils opening externally in large rounded apertures, rictal bristles short and inconspicuous; skull with nearimperforate interorbital septum, moderately-winged and -flared ectethmoids that are fused with the lachrymals and flattened with club-like tips against the jugal bar, a narrowed and vertically twisted palatine shelf to conform with bill compression, and broad, shallow and ill-defined temporal fossae that extend over the occiput and are flanked by short, fine postorbital and vestigial zygomatic processes; sternum broad with shallow keel c. ¼–⅓ x sternum width, lateral trabeculae short, c. ⅓ x length of sternum, hardly flared at tips, sternal rostrum reduced; wings short and rounded, primaries 10, with p10 moderately developed, p7–p5 longest, and p8=p4 or p3; humeral fossae single, very deep and trabeculated, the incisura capitis shallow, hardly developed into a tricipital groove, ventral tubercle short and rounded, and pectoral crest lengthened and decurrent below fossae; tail rather short and squaretipped, tail/wing ratio (0.62–)0.65–0.70(–0.72), the rectrices 12, straight-sided without terminal flaring, shallowly acute at tips; feet short but stout, with booted tarsi. Nest and eggs unrecorded. Arboreal, forest-living, weak-flying insectivores, gleaning by prying, digging and pounding actively with bill along tops and undersides of moss- and liverwort-draped branches and limbs; apparently monogamous.

Range and composition. Montane rainforests of New Guinea; one genus: Eulacestoma De Vis, 1894, of one species: E. nigropectus De Vis, 1894.