Psammogorgia teres Verrill, 1868

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 teres Verrill, 1868 Figures 15 , 16

Psammogorgia teres Verrill, 1868b: 416-417; Hickson 1915: 554; Kükenthal 1919: 237-238; Kükenthal 1924: 108; Harden 1979: 120.

Type material.

Lectotype (designated herein). YPM 1556b, dry, Pearl Islands, Gulf of Panamá, Panamá, F.H. Bradley, 1866-1867, no additional data.

Paralectotype. YPM 1556a, c, same data as the lectotype.

Type locality.

Pearl Islands, Panamá.

Diagnosis.

Colonies red or orange when preserved but brighter when alive. Colonies bushy and branch laterally and irregularly dichotomous. Stems vary from few millimetres up to 5 cm long, and 6 mm in diameter. Holdfasts encrusting with thin coenenchyme, often with polyps. Calyces flat, sparsely distributed all around the branches. Calyces with thorny, irregular spindles and wart-clubs around the calyx rim. Coenenchyme compact. Coenenchymal sclerites red, orange or colourless, mostly irregular warty spindles with acute or bifurcated ends and asymmetrical forms with prominent warty tubercles up to 0.20 mm long; wart-clubs with wide heads, up to 0.16 mm long; warty radiates and crosses. Anthocodial spindles pale yellow or colourless, flat or spiny, up to 0.26 mm long and in collaret and points arrangements. Coenenchymal sclerites red, orange and colourless, anthocodial rods pale yellow and colourless.

Description.

The lectotype is a red orange dry colony, which was brighter when alive ( Verrill 1868b), with 25 cm long and 20 cm wide (Fig. 15A, B ). The colony is bushy and laterally branched with an irregularly dichotomous pattern which branches up to 12 times (Fig. 15A, B ). The stem is 5 mm long and is 6 mm in diameter, arising from an oval holdfast with around 3.1 cm in diameter that bifurcates in two main branches. These branches are 5-6 mm thick at the base diminishing toward the tips to branchlets of around 3 mm in diameter (Fig. 15A ). The branches emerge at angles of 45-90°, ascending mostly parallel to each other and bifurcating the same way. Branchlets are mostly perpendicular to the branch of origin and slightly curved. Terminal branchlets are 5 to 60 mm in length (Fig. 15A ). Calyces occur all around the branches, being flat and with a polyp rim 0.4-1.0 mm in diameter and, mostly separated between each other by 0.5-4.0 mm with an average of 3.5 mm (Fig. 15B ). Calyces have concentration of thorny, irregular spindles and wart-clubs appearing usually around the calyx rim. The coenenchyme is compact with a finely granulated surface. The coenenchymal sclerites are very variable in size and form, being red, orange or colourless and mostly composed of irregular warty spindles with acute or bifurcated ends, and some asymmetrical forms with prominent warty tubercles (Figs 15C , 16A ). Spindles are 0.11-0.20 mm long and 0.07-0.12 mm wide. Wart-clubs have wide leafy heads and are 0.07-0.16 mm long and 0.045-0.10 mm wide (Fig. 16B ). Warty radiates are 0.07-0.13 mm long and 0.06-0.09 mm wide (Fig. 16C ); and some crosses, 0.95-0.11 mm by 0.08-0.11 mm (Fig. 16C ). The anthocodial armature is well developed and composed of pale-yellow to colourless spiny spindles and flat warty sclerites arranged in collaret and points, measuring 0.13-0.24 mm in length and 0.02-0.04 mm in width (Figs 15C , 16D ).

Remarks and comparison.

While the largest anthocodial sclerite measured in the lectotype was 0.24 mm long, Verrill (1886b) mentioned a slightly larger length of 0.26 mm. This is in accordance to the anthocodials of other specimens revised in this study. The syntype YPM1556b closely fits Verrill´s (1868b) description of the colony and the sclerites. For this reason, we designate this as the lectotype to clearly establish the species identity.

Psammogorgia teres has a colony morphology similar to that of P. fucosa (Table 1 ), but it has different sclerite sizes and colours in comparison with the type’s sclerite slide (Table 2 ). In P. teres , spindles and wart-clubs are shorter while anthocodials and radiates are larger than in P. fucosa (Table 2 ). Anthocodials of P. fucosa are red but colourless in P. teres , which is a diagnostic feature of this species.

In comparison with P. arbuscula and P. gracilis , P. teres differs in the external morphology represented by colonies with thicker branches and flat calyces; and relative abundance and sizes of sclerites (Tables 1 , 2 ).

Distribution.

The species occurs in Pearl Islands, Panamá (type locality) and also in in the Chiriquí Gulf, Panamá. However, the species presents a wider regional distribution in the tropical eastern Pacific. It was sampled by us, along the Pacific coast of Costa Rica, El Salvador, Nicaragua, and Ecuador, and encountered in collections from the Pacific coasts of México and Colombia.

Figures

Figure 15. Psammogorgia teres Verrill, 1868. YPM 1556 b A colony B detail of branches C Coenenchymal and anthocodial sclerites.

Figure 16. Psammogorgia teres Verrill, 1868. YPM 1556 b A spindles B Wart clubs C Radiates and crosses D anthocodial spindles.