taxonID	type	description	language	source
03DC878DFFACC92232ADFF1BFF308057.taxon	materials_examined	Material examined. LPVCMRMS 2022.701, LPVCMRMS 2023.702, Mostaganem, Algeria, 35 ° 57 ’ 55.80 ’’ N / 0 ° 05 ’ 30.85 ’’ E, May 2022, April 2023, 2 specs.	en	Benarous, Ahlam, Mezali, Karim (2026): Checklist of echinoderms caught as by-catch along the Algerian coast, with newly recorded species. Zootaxa 5750 (4): 547-563, DOI: 10.11646/zootaxa.5750.4.5, URL: https://doi.org/10.11646/zootaxa.5750.4.5
03DC878DFFACC92232ADFF1BFF308057.taxon	description	Description. Two specimens examined, minor radius “ r ” 24 mm and 10.5 mm, wet weight 9.20 g and 1.92 g, major radius “ R max ” 51 mm and 27 mm respectively. Body particularly flattened, pentagonal, irregular contour, wide proximal arms, triangular, approximately as long as wide, with a slight ridge marking the center of each arm (Figure 3 A). Abactinal surface orange (disappeared once preserved) with a darker center (Figure 3 D). Same color on the midline of the arms, covered with very small plates forming longitudinal and transverse rows, separated by slight grooves, each bearing 6 to 10 fine and short spines (Figure 3 E). A small madreporite plate located almost at the center (Figure 3 G). Actinal surface whitish. Each arm has a fine and straight ambulacral groove, in which two rows of light orange podia bearing suckers (Figure 3 B – C). Plates arranged in longitudinal and transverse rows, slightly larger than those on abactinal surface. Each plate bears a group of small, fine spines, their size decreasing towards the edges (Figure 3 H). Adambulacral plates bear a longitudinal row of five spines on their inner edge, joined along part of their length by a membrane, and an oblique row of four smaller spines on the outer edge (Figures 3 F, 3 I). Pedicellariae are absent in this species.	en	Benarous, Ahlam, Mezali, Karim (2026): Checklist of echinoderms caught as by-catch along the Algerian coast, with newly recorded species. Zootaxa 5750 (4): 547-563, DOI: 10.11646/zootaxa.5750.4.5, URL: https://doi.org/10.11646/zootaxa.5750.4.5
03DC878DFFADC92232ADFD3EFD498772.taxon	materials_examined	Material examined. LPVCMRMS 2024.801, LPVCMRMS 2024.802, LPVCMRMS 2024.803, LPVCMRMS 2024. 804, LPVCMRMS 2024.805, LPVCMRMS 2024.806, Annaba, Algeria, 36 ° 54 ’ 18.00 ’’ N / 7 ° 46 ’ 23.54 ’’ E, May 2024, 6 specs	en	Benarous, Ahlam, Mezali, Karim (2026): Checklist of echinoderms caught as by-catch along the Algerian coast, with newly recorded species. Zootaxa 5750 (4): 547-563, DOI: 10.11646/zootaxa.5750.4.5, URL: https://doi.org/10.11646/zootaxa.5750.4.5
03DC878DFFADC92232ADFD3EFD498772.taxon	description	Description. Six specimens examined, minor radius “ r ” 35.5 mm, 26.5 mm, 23 mm, 21 mm, 19.5 mm, and 13.5 mm, wet weight 58.12 g, 24.50 g, 19.56 g, 16.88 g, 16.89 g and 4.32 g respectively, major radius “ R max ” 51.5 mm, 34.1 mm, 33 mm, 30.5 mm, 26 mm, and 20 mm respectively. Body pentagonal, robust, resistant, arms slightly marked and curved, corners pentagon end with marked point (Figure 4 B). Bordered by large visible marginal plates (Figure 4 C), with 8 to 12 superomarginal plates on each side that are more prominent than the inferomarginal plates. These superomarginal plates show intraspecific variation, being longer than wide in some specimens and wider than long in others. Abactinal surface orange to brown (Figure 4 A), covered with plates arranged in longitudinal rows (Figure 4 D). These plates show fine granulation, including the madreporite plate (Figure 4 E). Actinal surface lighter in color (Figure 4 H), ambulacral grooves narrow with two rows of podia, covered with larger plates (Figure 4 F). Adambulacral plates covered by large granules arranged in several rows; the inner row comprises five slightly elongated granules and the second row only three; then rather irregular granules arranged in three more or less visible rows (Figure 4 G), these latter granules are hardly larger than those observed on the ventral plates. The other type of granulation is uniform across the entire body, slightly more pronounced on the actinal surface.	en	Benarous, Ahlam, Mezali, Karim (2026): Checklist of echinoderms caught as by-catch along the Algerian coast, with newly recorded species. Zootaxa 5750 (4): 547-563, DOI: 10.11646/zootaxa.5750.4.5, URL: https://doi.org/10.11646/zootaxa.5750.4.5
03DC878DFFADC92832ADF85AFD6783DA.taxon	materials_examined	Material examined. LPVCMRMS 2023.901, LPVCMRMS 2023.902, LPVCMRMS 2023.903, Mostaganem, Algeria 35 ° 57 ’ 55.80 ’’ N / 0 ° 05 ’ 30.85 ’’ E, April 2023, 3 specs. LPVCMRMS 2024.904, LPVCMRMS 2024.905, LPVCMRMS 2024.906, Annaba, Algeria, 36 ° 54 ’ 18.00 ’’ N / 7 ° 46 ’ 23.54 ’’ E, May 2024, 3 specs.	en	Benarous, Ahlam, Mezali, Karim (2026): Checklist of echinoderms caught as by-catch along the Algerian coast, with newly recorded species. Zootaxa 5750 (4): 547-563, DOI: 10.11646/zootaxa.5750.4.5, URL: https://doi.org/10.11646/zootaxa.5750.4.5
03DC878DFFADC92832ADF85AFD6783DA.taxon	description	Description. Six specimens examined, Annaba: wet weights 11.6 g, 15.12 g, and 21.8 g, diameter 3.8 cm, 5.6 cm, and 6.3 cm, height 2.4 cm, 4.6 cm, and 4.4 cm, respectively. Mostaganem: 106.5 g, 110.8 g, and 117.8 g, diameter 8.5 cm, 9.4 cm, and 10.8 cm, height 6.4 cm, 7.5 cm, and 7.9 cm, respectively. Body pentagonal, conical, circular contour, red with white stripes (Figure 5 A) flattened oral side (Figure 5 C). Meridian monochrome stripes often inconspicuous (Figure 5 D). Primary ambulacral tubercles present on each 2 plates (figure 5 D), numerous secondary ambulacral tubercles irregularly arranged. Large primary interambulacral tubercles present on every plate (figure 5 D), few secondary interambulacral tubercles above the ambitus, and more numerous and larger below. Spines sparse and few above ambitus, much more numerous and crowded on oral side, this spines of two sizes; primary spines long, reddish on the base, green and white on the apex. However, other variations are observed (Figure 5 A), secondary spines short; coloration varies from reddish to whitish (Figure 5 D). Numerous white ventral spines (Figure 5 C, 5 F). Generally, Gracilechinus acutus has the same appearance as Echinus melo Lamarck, 1816, and both species that have the same ecological niche are often confused. The main differences between the two species are as follows: a conical shape in Gracilechinus acutus, versus a spherical shape in E. melo; the test and spines of E. melo are often green; the arrangement of the primary interambulacral tubercles, which are present on all plates in G. acutus, but appear only on every second plate in E. melo; secondary tubercles small in E. melo and large in G. acutus, and the median zig-zag line is present only in E. melo. The arrangement of the primary interambulacral tubercles is one of the key features that distinguish G. acutus from other species in the genus Echinus, and has contributed to its reclassification as Gracilechinus acutus.	en	Benarous, Ahlam, Mezali, Karim (2026): Checklist of echinoderms caught as by-catch along the Algerian coast, with newly recorded species. Zootaxa 5750 (4): 547-563, DOI: 10.11646/zootaxa.5750.4.5, URL: https://doi.org/10.11646/zootaxa.5750.4.5
03DC878DFFADC92832ADF85AFD6783DA.taxon	discussion	Species diversity In this study, we identified 26 species of echinoderms collected as by-catch in the three sectors of the Algerian coast (West, Central, and East). Among the groups identified: 1) the Asteroidea were the most diverse class (with 9 recorded species), representing the highest proportion of the echinoderms (34.62 %), including 2 species that were recorded for the first time: Anseropoda placenta in the western Algerian coast, and Peltaster placenta in the East; 2) Echinoidea with 7 species (26.92 %), including the newly recorded Gracilechinus acutus; 3) Ophiuroidea represented by 6 species (23.08 %); 4) Holothuroidea by 3 species (11.54 %), and 4) Crinoidea by a single species (3.85 %). (Figure 6 A). Most echinoderm species counted in this study were captured on the western sector (almost 77 %), representing the highest species diversity observed in Algerian coast. In contrast, the Central and Eastern regions each report an identical proportion (61.54 %) (Figure 6 B). The updated census of echinoderm species along the Algerian coast, based on previous work: Allain et al. (1977); Mezali & Semroud (1997); Mezali (1998); Bakalem (2008); Mezali & Thandar (2014); Mezali et al. (2020, 2021, 2022, 2024); Khodja et al. (2021); Benarous & Mezali (2024), completed by the results of the present study, allowed the identification of a total of 72 echinoderm species (Table 2). Within the 72 recorded species, there are 19 Holothuroidea, 19 Ophiuroidea, 16 Asteroidea, 15 Echinoidea and 3 Crinoidea. Among these echinoderms recorded along the Algerian coast, Holothuroidea and Ophiuroidea are the most represented with an equal proportion of 26.39 %, followed by Asteroidea (22.22 %), Echinoidea (20.83 %), and the Crinoidea, which have the lowest percentage (4.17 %) (Figure 7). ...... continued on the next page According to Coll et al. (2010) (the only recent study that surveyed echinoderms across the entire Mediterranean basin), the Mediterranean Sea hosts a total of 154 echinoderm species, representing approximately 2.2 % of the marine biodiversity in the Mediterranean basin. In comparison, 72 echinoderm species have been recorded along the Algerian coast, representing 46.75 % of all echinoderm species in the Mediterranean. This shows that the Algerian basin represent an important echinoderm biodiversity reservoir. The echinoderms species recorded in the present study as by-catch, represent 36.11 % of the echinoderm diversity in Algerian coast and 16.88 % of that in the entire Mediterranean. Thus, echinoderms species captured as by-catches represents more than 1 / 3 of Algeria’s echinoderm diversity, confirming its potential as a supplementary data source for assessing benthic communities. The variation of the echinoderms specific richness among the three sectors of the Algerian coast reflects influence of environmental factors such as depth, substrate type, hydrodynamics, and the anthropogenic pressures. Moreover, the Algerian coast holds a strategic position in the Mediterranean Sea, with a coastline stretching over 2,148 km representing nearly 70 % of the southwestern Mediterranean, making it an ideal place for studying biodiversity and ecosystem conservation. The obtained data highlight the need to strengthen targeted monitoring and conservation efforts, particularly in hotspots areas, such as the western sector, in order to preserve benthic biodiversity and ensure sustainable management of marine ecosystems. It is essential to diversify sampling methods by integrating by-catch in order to obtain additional information for a more comprehensive assessment of local biodiversity. These neglected accidental catches are valuable biological resources that contribute to the enrichment of faunistic knowledge, especially for benthic organisms, particularly echinoderms and other marine invertebrates. Moreover, the relatively high diversity observed in the catches from small-scale fisheries suggests that artisanal gears could be an effective tool for longterm benthic biodiversity monitoring programs.	en	Benarous, Ahlam, Mezali, Karim (2026): Checklist of echinoderms caught as by-catch along the Algerian coast, with newly recorded species. Zootaxa 5750 (4): 547-563, DOI: 10.11646/zootaxa.5750.4.5, URL: https://doi.org/10.11646/zootaxa.5750.4.5
