Psammogorgia fucosa (Valenciennes, 1846), nomen dubium

Breedy, Odalisca & Guzman, Hector M., 2020, A revision of the genus Psammogorgia Verrill, 1868 (Cnidaria, Anthozoa, Octocorallia) in the tropical eastern Pacific Ocean, ZooKeys 961, pp. 1-30 : 1

Psammogorgia fucosa (Valenciennes, 1846), nomen dubium Figures 10 , 11

Gorgonia fucosa Valenciennes, 1846: pl. 15

Plexaura fucosa Milne-Edwards & Haime, 1857: 154; Valenciennes 1855: 12.

Psammogorgia fucosa Verrill, 1868b: 417; 1870: 556-557; 1869: 427; Kükenthal 1919: 237; Kükenthal 1924: 107; Harden 1979: 118-119.

Type locality.

Mazatlán, México, Pacific coast ( Valenciennes 1855).

Type material.

Plate 15, figured specimen ( Valenciennes 1846). MCZ ¨spicules du Gorgonia fucosa sclerite slide from MNHN. Holotype figured. Valenciennes material from 'Voyage autour du monde sur la frégate la Vénus, pendant les années 1836-1839' expedition was deposited in the MNHN; however, the specimen was not found in the museum (M. Castelin, MNHN, pers. comm. March 2018). The description below is based on Verrill (1868b), Bayer (1958), the figured specimen of Valenciennes (1846: plate 15), and MNHN sclerite slide (Fig. 10B ).

Diagnosis.

Colony dull reddish. Colonies bushy and irregularly dichotomous. Stems short and up to 12.5 mm in diameter. Branchlets up to 4.5 mm in diameter. Calyces flat, sparsely distributed all around the branches. Coenenchymal sclerites red, pink or colourless, mostly spindles up to 0.22 mm long; wart-clubs, up to 0.18 mm long; and warty radiates. Anthocodial spindles red, up to 0.21 mm long.

Description.

Valenciennes´ figured type was originally presented in natural size (Fig. 10A ). Verrill (1868b) reported this dull reddish specimen to be 25.4 cm long and 22.8 cm wide, with the branches ~ 3.8 mm wide. Approximately five stems arise from the holdfast, the thicker being around 12.5 mm in diameter. The colony branches up to 12 times. The branches are irregularly dichotomous, emerging at angles of 45-120°, mostly ascending in parallel and bifurcating at distances of 12.5 to 50.8 mm. The end branchlets are mostly crooked, scarcely tapering and obtuse or clavate at the tips with a diameter of 3-4.5 mm. Branchlets tips are ~ 12.7 to 25.4 mm long (Fig. 10A ). The calyces occur all around the branches but not close to each other (Fig. 10A ).

The coenenchymal sclerites vary remarkably in diversity of colour, size and form as Verrill has pointed out. Verrill found white, yellowish, light red, deep red and amethystine intermingled sclerites while we observed transparent, red and pink sclerites in the MNHN slide. The MNHN sclerites show a diversity of sclerites that is typical of the genus: mostly irregular warty spindles with acute, blunt or bifurcated ends, and several irregular forms (Figs 10B , 11 ). These sclerites measure 0.10-0.19 mm in length (reaching 0.22 mm according to Bayer (1858)) and 0.04-0.095 mm in width. Spindles commonly lack the naked median space as they are densely covered with warts. Few wart-clubs are found in the sample, 0.10-0.18 mm long and 0.04-0.06 mm wide at the expanded head. Radiates are densely covered by warts measuring 0.09-0.11 mm in length and 0.055-0.07 mm in width (Fig. 11 ). Anthocodial spindles are red, long, slender, and covered with small warts measuring 0.10-0.21 mm long and 0.01-0.02 mm wide (Fig. 11 ).

Remarks and comparison.

Verrill´s description of sclerites was based on the MNHN sclerite slide that was sent to him at the MCZ for analysis, probably by R.A. Kölliker ( Bayer 1958). We have also analysed sclerites from the slide, showing details that are difficult to compare with those of other species. Though, we found larger sizes of the sclerites than sizes given by Verrill (1870), as also observed by Bayer (1958). This species is similar to P. teres , in many aspects (see analysis below). It is indeed possible that P. fucosa is a synonym of P. teres ; however, without a specimen to examine we prefer to keep the status of P. fucosa as dubious.

Distribution.

Tropical eastern Pacific: only reported from the type locality at Mazatlán, México.

Figures

Figure 10. Psammogorgia fucosa Valenciennes, 1846 A original figure of the holotype, Valenciennes 1846: plate 15 B microscopic slide with sclerites deposited at MNHN.

Figure 11. Psammogorgia fucosa Valenciennes, 1846. Coenenchymal and anthocodial sclerites, in stereomicroscope. Photographs: Jennifer Winifred Trimble IZ Curatorial Assistant, MCZ, 2018.