Galkinius Perreault, 2014

Chan, Benny Kwok Kan & Liu, Jennie Chien Wen, 2017, Galkinius Perreault, 2014 or Darwiniella (Anderson, 1992)? A new coral-associated barnacle sharing characteristics of these two genera in Pacific waters (Crustacea, Cirripedia, Thoracica, Pyrgomatidae), ZooKeys 719, pp. 1-22 : 3-4

Genus Galkinius Perreault, 2014

Diagnosis (emended).

Shell wall fused or four plated, flat, with high radial ridges at the junction with coral skeleton. Scutum and tergum fused, the two parts being approximately subequal. Adductor ridge and lateral depressor muscle scars absent, adductor plate and rostral tooth present. Tergal spur well developed and wide. Apertural frill coloured and spotted. Maxilla and cirri with numerous dark spots and bands.

Type species.

Galkinius indica (Annandale, 1924).

Remarks.

In the original diagnosis of Galkinius , the shell consisted of four separated plates and the fused scutum and tergum, which differs from Darwiniella which has a fused shell as well as a fused scutum and tergum. In the present study, a new species of Galkinius was identified as having a fused shell wall. Therefore it is necessary to emend the diagnosis of Galkinius to accommodate this species (see discussion below). Galkinius differs from Darwiniella in having much wider tergal spur and tergal furrow. Height of the adductor ridge of the scutum in Darwiniella is much greater than in species of Galkinius . In Darwiniella , the height of adductor ridge is approximately 2/3 to 1/2 total height of scutum. In Galkinius , height of adductor plate is often approximately 1/3 of the total height of scutum. Maxilla of Galkinius and cirri with large number of coloured spots and bands, when compared to Darwiniella . The apertural frills of Darwniella angularis and D. conjugatum are white, while Galkinius has a coloured or spotted aperture frill.