Ophiocoma (Breviturma) krohi Stöhr, Boissin & Hoareau, 2013

Boissin, Emilie, Hoareau, Thierry B., Paulay, Gustav & Bruggemann, J. Henrich, 2016, Shallow-water reef ophiuroids (Echinodermata: Ophiuroidea) of Réunion (Mascarene Islands), with biogeographic considerations, Zootaxa 4098 (2), pp. 273-297 : 283

Ophiocoma (Breviturma) krohi Stöhr, Boissin & Hoareau, 2013 .

(UF-6454, Fig. 3 i, KC759802 )

Material. 2 spms, St. 1; 3 spms, St. 2; 15 spms, St. 3; 5 spms, St. 5; 19 spms, St. 8

Remarks. A species of Ophiocoma that was previously confused with O. dentata was recently described based on material from this survey ( Stöhr et al., 2013). It can be distinguished from O. dentata by the number of arm spines: five (instead of four) spines on the 5th and 6th segments, followed by four (instead of three) and finally three spines on more distal segments. The two species also differ in the density of disc granulation. Specimens are usually smaller than other Ophiocoma (Breviturma) , with a mean DD of about 8 mm; but do not correspond to juveniles of these three species, also observed during this survey. Although the colour pattern is highly variable, four forms can be roughly delineated: (1) mottled olive/brown disc and arms, (2) yellow/beige and brown, with darker lines outlining each arm plate, (3) uniformly black, and (4) black, with sparse white on disc and arms. These colour forms are not differentiated in mtDNA sequences and appear to be intraspecific variations rather than cryptic species. COI sequence data shows little genetic differentiation across the range of this species (Hoareau et al. 2013 as Ophiocoma sp. nov.). Abundance: 3.

Distribution. Described from Réunion, Stöhr et al. (2013) noted that the species is widespread in the IWP, but did not provide specific localities. The UF collections hold material of O. krohi from the Mariana Islands, Wake Island, Society Islands, Samoa, Niue, Palau, Hawaii and Okinawa.

Figures

FIGURE 3. Pictures of species encountered in Réunion Island waters. Pictures were taken of freshly collected specimens except when indicated. Photo credit: BIOTAS.