Stricosus madanii Sabir and Theriot, 2018

Sabir, J. S. M., Theriot, E. C., Lobban, C. S., Alhebshi, A. M., Al-Malki, A. L., Hajrah, N. H., Khiyami, M. A., Obaid, A. Y., Jansen, R. K. & Ashworth, M. A., 2018, Systematics of araphid diatoms with asymmetric rimoportulae or densely packed virgae, with particular attention to Hyalosynedra (Ulnariaceae, Bacillariophyta), Phytotaxa 347 (1), pp. 1-49 : 40-42

publication ID	https://doi.org/ 10.11646/phytotaxa.347.1.1
DOI	https://doi.org/10.5281/zenodo.13708511
persistent identifier	https://treatment.plazi.org/id/A57F87E7-FFE5-EA6E-FF5B-FE83FC32FD6E
treatment provided by	Felipe
scientific name	Stricosus madanii Sabir and Theriot
status	sp. nov.

Treatment

Stricosus madanii Sabir and Theriot sp. nov. ( Figs 104–111 View FIGURES 104–107 View FIGURES 108–111 )

Holotype: — ANSP G.C. 38101

Isotype: — UTKSA 0065

Type locality: —Obhur near Jeddah, Makkah Province, Saudi Arabia (21° 43.535’ N, 39° 06.949’ E).

Material studied: Wild and cultured ( UTKSA 0065, KSA 0171) material isolated from type locality: SA 29, sediment collected from the submerged rocky bottom at the Obhur area of Jeddah, Kingdom of Saudi Arabia (21° 43.535’ N, 39° 06.949’ E).

Description: —Valves of this robustly shaped species were observed to be 51.9–137.4 μm long and 6.1–9.2 μm wide. Sides were parallel for much of the valve length for most valves; a few valves were even slightly concave in the middle, widening towards the poles ( Figs 104–108 View FIGURES 104–107 View FIGURES 108–111 ). Margins became slightly convex towards the apices and converged to a rounded end. Apices were never observed to be capitate. The sternum was prominent but evenly thin along the length of the valve ( Figs 104–107 View FIGURES 104–107 ). Virga spacing was visible in the LM, more prominently than on the valves of most other species, and was measured at 40–43 in 10 μm. The deeply sunken ocellulimbi were 6–14 pores wide and 6–8 pores tall, and overhung by 1–3 spines ( Fig. 109 View FIGURES 108–111 ). The specimens had a rimoportula at each pole with unusual internal morphology. The covers bordering the aperture were elongated and oblique to the transapical axis, but the slit and covers were sinuous ( Figs 110, 111 View FIGURES 108–111 ). The external rimoportula pores were about 1.6–2.4 μm from the end of the valve ( Fig. 109 View FIGURES 108–111 ). Striae were biseriate and walls were bilayered, again with a single pore internally. Girdle bands were open and without pores ( Fig 109 View FIGURES 108–111 ).

Remarks: —Unlike other the species studied here, S. madanii has a very distinct outline and robust appearance, and was relatively wide for its length. The sinuous rimoportula lips and slit were also unique among diatoms studied.

Etymology: —Named in honor of Prof. Dr. Ghazi Obaid Madani, Former President of King Abdulaziz University (KAU), Jeddah, Saudi Arabia, for his contributions to scientific research.