Amphipholis Ljungman, 1866

Alitto, Renata A. S., Bueno, Maristela L., Guilherme, Pablo D. B., Domenico, Maikon Di, Christensen, Ana Beardsley & Borges, Michela, 2018, Shallow-water brittle stars (Echinodermata: Ophiuroidea) from Araçá Bay (Southeastern Brazil), with spatial distribution considerations, Zootaxa 4405 (1), pp. 1-66 : 40

Genus Amphipholis Ljungman, 1866

Type taxon. Amphipholis januarii Ljungman, 1866 .

Diagnosis. Disc with scales dorsally and ventrally, without spines. Radial shields contiguous for almost their entire length or separated proximally by up to four scales. Two lateral oral papillae, distal one much larger and widened. Two tentacle scales. Three to four arm spines, usually small and pointed ( Ljungman 1867; Verrill 1899a; Thomas 1962; Clark 1970; Tommasi 1970; Albuquerque 1986).

Comments. Amphipholis was described from Amphipholis januarii collected from Rio de Janeiro, Brazil ( Ljungman 1866). In 1872, an identification key was constructed with a total of 27 species ( Ljungman 1872). Amphipholis has undergone several revisions. One of these divided the genus into three groups according to the number of tentacle scales ( Fell 1962). This proposal was not accepted by Thomas (1966), who recommended organizing into three genera, including Micropholis (now Microphiopholis ) and Axiognathus . This classification was accepted by Tommasi (1970), but questioned by Clark (1970) due to the proximity between A. januarii and A. squamata , type taxon of genus Axiognathus and Amphipholis respectively. Currently, Axiognathus is invalid and accepted as Amphipholis ( Stöhr et al. 2016) . Amphipholis is similar to Amphiodia , but the main difference between them is the shape and size of the distal oral papilla. In Amphipholis it is large, greater than the proximal one, rectangular and wide, tending to cover the oral slit. In Amphiodia the distal lateral oral papilla is circular or triangular ( Verrill 1899a). Currently, 26 species are accepted ( Stöhr et al. 2016), two of which are recorded from Brazil ( Barboza & Borges 2012): A. januarii Ljungman, 1866 and A. squamata ( Delle Chiaje, 1828) .