Catenula komodensis Witkowski, Risjani, Yunianta, M. Rybak & Luthfi, 2024

Luthfi, Oktiyas Muzaky, Arsad, Sulastri, Kryk, Adrian, Risjani, Yenny, Yunianta,, Rybak, Mateusz, Peszek, Łukasz, Wróbel, Rafał J., Pappas, Janice L., Bąk, Małgorzata & Witkowski, Andrzej, 2024, New genera and new species of Catenulaceae (Bacillariophyta) from Coral Reef habitat of two Indonesia islands — Bawean and Sulawesi — A morphological approach, PhytoKeys 248, pp. 263-291 : 263-291

Catenula komodensis Witkowski, Risjani, Yunianta, M. Rybak & Luthfi sp. nov.

Type materials.

Holotype: Slide number SZCZ 27552 at repository of University of Szczecin.

Isotype: Slide number SZCZ 28814 at repository of University of Szczecin (Fig. 8 N ) .

Type locality.

Sand and coral boulders of coral reef at Gili Iyang harbour Bawean Island, East Java, Indonesia.

Etymology.

The species name is derived from the Komodo dragon that is endemic to 4 islands: Komodo, Rinca, Flores, and Gili Motang, East Nusa Tenggara, Indonesia.

Distribution.

The diatom species C. komodensis is distributed on Bawean and Sulawesi Islands, Indonesia.

Description.

Light microscopy (Fig. 8 A – K ): The valves are lanceolate, dorsiventral to linear-lanceolate with straight to less convex margins. Apices are narrowly pointed. Thickened silica in the central area was observed clearly on some valves under LM. Valve length 8.3–15.6 µm, n = 13 and width 1.7–2.6 µm, n = 13.

Scanning electron microscopy (Fig. 8 L – U ): Valve face flat, abruptly transitioning to mantle. Raphe filiform, positioned near ventral margin externally and internally (Fig. 8 L – N, T – U ). External raphe slits arcuate; proximal endings simple, dorsally oriented, distantly spaced (1.1–1.9 μm). Distal raphe endings simple, terminating 0.8–2.8 μm from apices. Areolae absent on dorsal and ventral valve surfaces. Dorsal side exhibits shallow or indistinct parallel grooves. Internal raphe slits curved; apical endings deflected dorsally (Fig. 8 T – U ). Internal distal raphe endings simple, without fissures, terminating 1.7–1.8 μm from apices. Helictoglossae indistinct (Fig. 8 S ). Dorsal and ventral sides striated; areolae occluded by dome-like structures. Striae density slightly lower dorsally; secondary silica deposition observed on ventral valve side (Fig. 8 U ). Striae density 34–35 in 10 μm ventrally, 35 in 10 μm dorsally (n = 13).

Figures

Figure 8. Catenula komodensis Witkowski, Risjani, Yunianta, M. Rybak & Luthfi, sp. nov. A – K light micrographs L – U SEM images. L – N external view on entire frustules; note a row of slit-like ventral and dorsal mantles (arrowheads) O detail of proximal raphe ending, externally P detail of apical raphe ending, externally Q – S detail of internal proximal raphe ending, arcuate raphe slit and distal raphe ending, respectively; note a row of linear small protruding flaps (R arrowhead) T – U internal valve view with 2 thickenings of silica on central area and near slit ends (U arrowheads). Scale bar: 10 µm (A – K).