identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
039A87AD4229014C61C7FC13FB0E0BD6.text	039A87AD4229014C61C7FC13FB0E0BD6.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Afrocymbella pseudodelphinea Rutakaza Nzigire & Cocquyt 2026	<div><p>Afrocymbella pseudodelphinea Rutakaza Nzigire &amp; Cocquyt sp. nov.</p><p>http://phycobank.org/106046</p><p>Figs 2–4</p><p>Etymology</p><p>The new taxon shows some morphological resemblances to Afrocymbella delphinea Jeff.R.Stone, M.C.Wilson &amp; Jovanovska recently described from Lake Malawi, hence the epithet pseudodelphinea .</p><p>Type material</p><p>Holotype</p><p>DEMOCRATIC REPUBLIC OF THE CONGO • <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=29.383333&amp;materialsCitation.latitude=-0.4" title="Search Plazi for locations around (long 29.383333/lat -0.4)">Lake Edward</a>, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=29.383333&amp;materialsCitation.latitude=-0.4" title="Search Plazi for locations around (long 29.383333/lat -0.4)">Bugazia</a>; 0°24′00″ S, 29°23′00″ E; ca 912 m a.s.l.; 25 Jun. 1935; from gut content of Oreochromis leucostictus RMCA P. 65674 collected by Hubert Damas; BR [BR4859]. The valve representative of the species is here illustrated in Fig. 2L.</p><p>Description</p><p>Light microscopy (Fig. 2)</p><p>Valves dorsiventral and heteropolar, lanceolate to semi rhomboid-lanceolate. Dorsal margin distinctly arched, ventral margin tumescent. Headpole broadly rounded and slightly rostrate. Protracted footpole, particularly prominent in smaller valves, slightly bent to the ventral side. Valves 34.5–60.0 µm long and 11.0–13.5 µm wide (n = 40). Length-to-width ratio: 3.1–4.4 (3.7). Striae radiate throughout the valve, 13–17 in 10 µm (n = 40), slightly curved, somewhat coarser and sometimes unevenly spaced near the central area (12–15 in 10 µm) and denser towards the poles (16–18 in 10 µm). Shortened stria sometimes present on the dorsal side near the central nodule. Density of the striae in some valves higher on the dorsal than the ventral sides. Striae composed of 26–30 areolae in 10 µm, rarely reaching up to 32 in 10 µm. Axial area narrow, slightly curved, ventrally displaced and somewhat enlarged on the dorsal side near the central nodule. Central area small, elliptical, wider on the dorsal side and often almost absent on the ventral side. A distinct stigmoid present on the central nodule, in the extension of the dorsal middle stria. Raphe curved and slightly sinusoidal. Raphe slit shorter between headpole and central nodule than between footpole and central nodule. Apical pore field (APF) near the footpole small, divided into a dorsal and ventral part by the terminal raphe fissure.</p><p>Scanning electron microscopy (Figs 3–4) Externally, striae composed of apically elongated and ellipsoidal areolae, continuous on the valve mantle. External proximal raphe ends expanded into rounded pores. Raphe slit curved dorsally at both apices, external distal raphe fissures widened and deflected ventrally. Stigmoid externally round. APF at the foot pole small, divided by the terminal raphe fissure into a dorsal and a ventral part. The delimitation of the APF towards the last striae in the valve face can be more or less straight or with two shorter rows of small poroids, shortened by two poroids. Internally, areolae are ellipsoid to circular and located in alveoli occluded with a velum. Internal distal raphe endings slightly elevated into small helictoglossa. Stigmoid internally large, transapically elongated narrow furrow, weakly connected to the shortened middle dorsal alveolus and slightly broadened near the central nodule. Internal central raphe endings complex and composed of an antler-shaped part that spans 3–5 alveoli that is gently convexly curved parallel to the raphe slit and with enlarged ends. The antler-shaped part is connected to the intermissio without a transapically slit. Small pseudoseptum present at both apical poles.</p><p>Girdle consist of at least three bands: a short open band near the apex, a band with a row of small round poroids, about 20 in 10 µm and a rather broad band with one row of elongated poroids, about 40 in 10 µm (Fig. 4A). Septum not observed.</p><p>Taxonomic remarks</p><p>Afrocymbella pseudodelphinea sp. nov. can be distinguished from other taxa of Afrocymbella in having ellipsoid areolae externally and the antler-shaped part of the complex intermissio without the transapically slit but sitting on the central raphe fissures (Fig. 4D arrow). To our knowledge, this is the first observation of alveoli being occluded by an apparent velum in any species of Afrocymbella . The structure is clearly visible in SEM images (Fig.4D). We believe the vela were preserved due to the gentle cleaning procedure (using only H 2 O 2 and no potassium permanganate nor acids such as sulphuric or nitric acid) and the unique origin of our samples (fish gut contents), which likely limited mechanical and chemical damage. The presence of a velum may therefore be a previously undetected but genuine morphological feature within Afrocymbella . Afrocymbella pseudodelphinea is morphologically resembling A. beccarii in general valve symmetry and dimensions. However, the new species can be distinguished by its broader, more rounded valve outline and the presence of round areolae (poroids) visible under SEM, in contrast to the slit-like poroids described for A. beccarii by Krammer (2003).</p><p>An image given in Kociolek &amp; Stoermer (1993a: 73, fig. 4) shows a valve with similar outline features to A. pseudodelphinea sp. nov. This points to the possibility of prior unrecognized observations of the new taxon. The same authors also noted the presence of subfossil A. beccarii specimens with round areolae, although no illustrations of these valves were provided. Without comparative images or reinvestigation of the material, it remains unclear whether those specimens correspond to A. pseudodelphinea . It is possible that the valves with the rounded areolae observed by Kociolek &amp; Stoermer (1993a) are morphologically closer to A. pseudodelphinea and may represent a misidentification or cryptic diversity within A. beccarii .</p><p>The fact that A. pseudodelphinea sp. nov. was observed only in a historical sample (RMCA P.65674), and has not been found in more recent collections, raises questions about its ecological status. It may represent a rarely occurring extant species or a species threatened with extinction. Nonetheless, based on its distinct morphological and consistent characteristics, we are convinced that A. pseudodelphinea is indeed a new species. We hope future molecular data can support this.</p><p>Ecology</p><p>Afrocymbella pseudodelphinea sp. nov. was abundant in the gut of the historical sample of Oreochromis leucostictus (RMCA P.65674), comprising 31.7% of the total algal composition. Diatoms dominated the gut content (78.4%), which was also filled with fine sediment and mud. Most diatom taxa observed were benthic, including Ulnaria (Kützing) Compère sp. (16.4%), suggesting a likely benthic or periphytic habitat for A. pseudodelphinea . Besides Ulnaria sp., other diatoms such as Cyclostephanos damasii (Hustedt) Stoermer &amp; Håkansson and Nitzschia Hassall sp. were observed, as well as various chlorophytes (e.g., Coelastrum Nägeli sp., Tetraedon Kützing sp., Cosmarium Corda ex Ralfs spp., Oocystis Nägeli &amp; A.Braun spp., Scenedesmus Meyen spp.). Cyanobacteria, on the other hand, were rare and limited to the following taxa: Limnococcus limneticus (Lemmermann) Komárková, Jezberová, O.Komárek &amp; Zapomelová (basionym: Chroococcus limneticus Lemmermann) and Merismopedia Meyen spp.</p><p>Several valves of the new species exhibited broken APF, which may reflect mechanical abrasion. While such damage could occur during grazing, it can also result from post-mortem degradation or sediment transport. The collecting site (Bugazia) is characterized by rocky shorelines, supporting the presence of periphytic diatoms. However, due to the non-selective feeding behaviour of O. leucostictus (Trewavas 1983; Keyombe et al. 2017), which consumes both benthic and suspended material, this ecological interpretation should be considered provisional pending further environmental sampling.</p><p>Distribution</p><p>To date, Afrocymbella pseudodelphinea sp. nov. has only been observed in the gut of a single specimen of Oreochromis leucostictus (RMCA P. 65674), collected by Hubert Damas in 1935 in Bugazia at the Congolese part of Lake Edward (Fig. 1). The new species was not found in any other samples of the intestinal contents of the fishes we analysed (only one occurrence among 60 individuals examined), and is therefore likely to have a restricted distribution. However, its rarity may also be due to limited sampling as only two fish specimens from the historical 1935 Congolese collection were available for analysis during the present study. In contrast, a more substantial number of fish specimens (58 individuals) were analysed from recent collections conducted on the Ugandan side of Lake Edward, and A. pseudodelphinea was not detected in any of them. Unfortunately, due to limited access in recent decades, no recent samples from the Congolese side of Lake Edward are available. Therefore, the current distribution of the new species cannot be confirmed or explained. Further sampling, particularly in understudied areas and habitats, is necessary to clarify the ecological niche and distributional range of the new species.</p></div>	https://treatment.plazi.org/id/039A87AD4229014C61C7FC13FB0E0BD6	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Nzigire, Elysée Rutakaza;Steenberge, Maarten Van;Bazairi, Hocein;Cocquyt, Christine	Nzigire, Elysée Rutakaza, Steenberge, Maarten Van, Bazairi, Hocein, Cocquyt, Christine (2026): Observations of Afrocymbella Krammer (Cymbellales, Bacillariophyta) in the guts of the cichlid fish Oreochromis leucostictus (Trewavas, 1933) from the Edward-George system, East Africa, with the description of a new species. European Journal of Taxonomy 1048: 111-141, DOI: 10.5852/ejt.2026.1048.3241, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3241/14353
039A87AD42240156625CFC80FE0108F3.text	039A87AD42240156625CFC80FE0108F3.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Afrocymbella beccarii (Grunow) Krammer	<div><p>Afrocymbella beccarii (Grunow) Krammer</p><p>Figs 5–7, 9–11</p><p>Afrocymbella beccarii (Grunow) Krammer (Krammer 2003: 131, pl. 145 figs 4–6, pl. 146 figs 2–7, pl. 147 figs 1–9, pl. 149 fig. 3). – Cymbella beccarii Grunow (Grunow 1886: 152, fig. 1: 1–2). – Gomphocymbella beccarii (Grunow) Forti (Forti 1910: 1277).</p><p>Gomphonema brunii Fricke (Fricke 1902: pl. 238: figs 12–14 (as G. Bruni). – Gomphocymbella brunii (Fricke) O.Müller (Müller 1905: 150 part, only fig. 1: 3). – Type: A. Schmidt et al. 1902: pl. 238 figs 13–14.</p><p>Type material</p><p>Type</p><p>“ ABISSINIA” [ERITREA] • “Sciotel, alle falde dello Zedamba” [ Shotel: on the slopes of Zedamba = Tsad-Amba]; 1870; Beccari leg.; holotype: Grunow 1886 fig. 1: 1–2 (no original specimen available) .</p><p>Epitype</p><p>TANZANIA • Lake Victoria (Victoria Nyanza), Mwanza Gulf; 12 May 1983; Hans van den Heuvel leg.; on stones; slide 1008C IOK; Hustedt Collection; BGBM .</p><p>Material examined</p><p>TANZANIA • Lake Victoria, Mwanza Gulf, Nyegezi Bay; 12 May 1983; Hans van den Heuvel leg.; collected on rocks at 10 cm depth; sample MG 28; personal collection Hans van den Heuvel .</p><p>UGANDA • <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=29.885&amp;materialsCitation.latitude=-0.209" title="Search Plazi for locations around (long 29.885/lat -0.209)">lake Edward-George system</a>, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=29.885&amp;materialsCitation.latitude=-0.209" title="Search Plazi for locations around (long 29.885/lat -0.209)">Kazinga Channel</a>; 0°12′32.4″ S, 29°53′06.0″ E; ca 912 m a.s.l.; 24 Oct. 2016; from gut content of Oreochromis leucostictus RMCA 2016.035.P.0266 and RMCA 2016.035.P.1111 collected by 2016 HIPE; BR .</p><p>Description</p><p>LM observations (Fig. 5)</p><p>Valve length 36.0–69.5 µm, valve width 10.0–12.5 µm (n = 20). Length-to-width ratio: 4.4. Valves distinctly dorsiventral and heteropolar, lanceolate to semi rhomboid-lanceolate. Dorsal margin broadly arched, slightly protracted near the apices. Ventral margin weakly convex, barely tumescent in central area, tapering gently toward the apices. Axial area narrow, curved, slightly ventrally displaced. Central area small, broadly elliptical, slightly more arched on dorsal side. Striae parallel to slightly radiate in the middle, becoming more radiate towards the valve apices, sometimes unevenly spaced near the central area (12–14 in 10 µm) and denser towards the poles (15–17 in 10 µm). Stria density different on both sides: slightly higher density on the dorsal side (13–14 striae in 10 µm in the middle part) than on the ventral side (12–13 striae in 10 µm in the middle part). Striae composed of 24–28 areolae in 10 µm (n = 20). Central area small, elliptical, wider on the dorsal side. A distinct stigmoid present on the central nodule, in the extension of the dorsal middle stria. Raphe curved and slightly sinusoidal.</p><p>SEM observations (Figs 6–7)</p><p>Footpole narrowing, rounded with APF, headpole rostrate. APF externally with small round poroids. Stigmoid externally round. Raphe curved and slightly sinusoidal. External proximal raphe fissures expanded into small rounded pores. External distal raphe terminal fissures deflected towards the ventral margin. Striae continue uninterrupted onto the valve mantle. External areolae slit-like poroids. APF small, divided by the terminal raphe fissure into a dorsal and a ventral part. The delimitation of the APF towards the last stria on the valve face in two steps with two shorter rows of small poroids, shortened by one and two poroids respectively. Internally, no vela occluding the alveoli observed. Stigmoid a large, elongated slit, distally not connected to the shortened middle dorsal alveolus and proximally widened near the central nodule. Internal central raphe endings complex and composed of an antler-shaped part that spans 5 alveoli that is only slightly convexly curved parallel to the raphe and with slightly bent and enlarged endings. The antler-shaped part is connected to the intermissio through a short transapically slit. Girdle consists of at least three open bands: a rather broad band with one row of elongated poroids, about 50 in 10 µm. Septum not observed.</p><p>Taxonomic remarks</p><p>Afrocymbella beccarii described by Grunow (1886) from “ Abissinia ” and A. brunii described by Fricke (1902) from German East Africa (comprising present day Rwanda, Burundi and Tanzania) were regarded as conspecific by Müller (1905).Afterwards, among others Forti (1910), Hustedt (1949), Van Meel (1954), Gasse (1986), Kociolek &amp; Stoermer (1993a), Cocquyt (1998) and Krammer (2003), followed Müller’s (1905) interpretation by treating A. brunii as a synonym of A. beccarii . However, Shinohara et al. (2014) re-evaluated this interpretation and recognised A. brunii and A. beccarii as two distinct species based on differences in valve morphology.</p><p>Based on a comparative analysis of historical illustrations and our own observations, we support the synonymisation of A. brunii with A. beccarii . The valves illustrated by Shinohara et al. (2014: fig. 2a–h) do not closely resemble A. brunii as originally described by Fricke (1902), but instead show a greater resemblance to a large species of Afrocymbella, A. pergracilis Krammer (Krammer 2003: pl. 150, figs 1–5). Moreover, the findings of Shinohara et al. (2014) were based on the investigation of material from Lake Malawi, not including the epitype material from Mwanza Gulf in Lake Victoria (Tanzania) or, by absence of it, material close to the type locality. Despite these discrepancies, Stone et al. (2022) followed the interpretation of Shinohara et al. (2014) and identified morphologically resembling valves as A. brunii in material from lakes Tanganyika and Malawi (Stone et al. 2022: figs 148–151).</p><p>Stone et al. (2022) described a species of Afrocymbella, A. cocquytiana, from the Kalambo Falls near the southern end of Lake Tanganyika on the boundary between Tanzania and Zambia that shares significant morphological similarities with A. beccarii .</p><p>Ecology</p><p>Afrocymbella beccarii was observed in low numbers in the guts of the two specimens of Oreochromis leucostictus (2.1% in RMCA 2016.035.P.0266 and 8.7% in RMCA 2016.035.P.1111). The guts were dominated by planktonic Cyanobacteria, namely Microcystis Kützing spp. (74.9% in RMCA 2016.035.P.0266 and 22.6% in RMCA 2016.035.P.1111), Planktolyngbya contorta (Lemmermann) Anagnostidis &amp; Komárek (3.7% in RMCA 2016.035.P.0266 and 16.04% in RMCA 2016.035.P.1111) and Chroococcus limneticus (16.34% in RMCA 2016.035.P.1111). This dominance of Cyanobacteria can be explained by the fact that these fish were caught at the mouth of Kazinga Channel (near Katwe Bay), an offshore site, where water is under influence of the rich waters of Lake George entering Lake Edward via the Kazinga Channel. Stoyneva-Gärtner et al. (2020) already reported that Cyanobacteria are by far the most abundant group at that place. Moreover, the dominant Cyanobacteria are planktonic species, suggesting that the fish were feeding on the plankton. We noted that the APF of A. beccarii valves observed were intact. These observations may suggest that A. beccarii was ingested by O. leucostictus as part of incidental planktivorous ingestion rather than by grazing on benthic or epiphytic biofilms. According to Cholnoky (1968), the pH optimum for A. beccarii, the most widely-distributed species of the genus, is around eight.</p><p>Distribution</p><p>In this study, A. beccarii was identified in the gut contents of two specimens of Oreochromis leucostictus (RMCA 2016.035.P.0266 and RMCA 2016.035.P.1111), collected near Mwenya at the mouth of the Kazinga Channel (Lake Edward, Uganda) during the 2016 HIPE campaign (Fig. 1). This represents a novel observation of the species for Lake Edward although in an intestinal context.</p><p>Previous East African records include benthic samples from Bugazia, Kamande, and mouth of the Mosenda River on the Congolese side of Lake Edward, as well as planktonic occurrences from Bugazia, Kamande, and Hangi (Hustedt 1949). The species was also found in phytoplankton from Lake George and the Kazinga Channel (Hustedt 1949), and in bottom mud samples from Lake Edward (Gasse 1986). Haworth (1977) confirmed its presence in both Lake Edward and Lake George. Additional benthic and planktonic occurrences have been reported from Lake Kivu localities including Goma, Kisenyi, Keshero, and Gabiro-Nangero in Rwanda and DRC, as well as the Semliki River (DRC) (Hustedt 1949). Krammer (2003) reported A. beccarii as widespread across the East African Rift Valley lakes, including Lake Victoria (e.g., Mwanza Gulf, Tanzania), Lake Tanganyika, and even a temporary lake near the desert margin in Libya, although the latter lacks a precise source. Cocquyt et al. (1993) listed it in the algal flora of lakes Victoria, Tanganyika, and Malawi. Kociolek &amp; Stoermer (1993a) found A. beccarii (under its synonym A. brunii) as an epiphyte in Lake Turkana (Kenya) and in sediment cores from Lake Tanganyika. Mpawenayo (1996) observed this taxon in the Rusizi plain in Burundi, while Golama (1996) recorded A. beccarii as an epiphyte on stones near the Wagenia Falls in Kisangani (DRC). Ross (1983) mentioned records of the species from Benin (formerly Dahomey), Lake Chad, Libya, Sierra Leone and Zimbabwe beside lakes Malawi, Tanganyika, Kivu, Edward, Victoria and Turkana. De Toni &amp; Forti (1914), reported A. beccarii as epiphytic in Tarhuna, a locality in Libya rather close to the Mediterranean Sea. For west Africa, Woodhead &amp; Tweed (1958) cited A. beccarii among the algae of Dahomey (present-day Benin). Afrocymbella beccarii was originally described as Cymbella beccarii Grunow (1886) from “ Abissinia ”. An additional record was reported from Sciotel, located in Eritrea (Forti 1910). Under its synonymy name Afrocymbella brunii the taxon was reported from Lake Edward (Rich 1933) as well as in the plankton of Lake Malawi and surrounding water bodies including Lake Malomba, Lake Ngozi, the Mbasi River, and the Songwe River (Müller 1905), supporting the species’ broad historical and geographical distribution.</p><p>An ANCOVA on valve width in relation to valve length, applied to Afrocymbella pseudodelphinea sp. nov., A. beccarii from Lake Edward, A. beccarii from Mwanza Gulf, and A. cocquytiana from the Kalambo River (Stone et al. 2022) show significant differences in valve shape among populations and species of Afrocymbella (p = 0.00012) (Fig. 8). Afrocymbella beccarii from Lake Edward exhibited the steepest slope (0.161), which may indicate a rapid decrease in valve length during the vegetative reproduction, resulting in wider valves for the smaller cells. In contrast, A. beccarii from Mwanza Gulf showed a shallower slope (0.058), reflecting a more slender valve length decrease. Concerning A. pseudodelphinea and A. cocquytiana, the first taxon displayed a moderate slope (0.075), while the latter showed the lowest slope (0.047), indicating compact, narrow valves with minimal widening relative to length. All slopes differ significantly by ANCOVA (interaction term F(3, 99) = 7.64, p = 0.00012). The differences in allometric highlight morphological divergence both between species and among populations within A. beccarii .</p></div>	https://treatment.plazi.org/id/039A87AD42240156625CFC80FE0108F3	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Nzigire, Elysée Rutakaza;Steenberge, Maarten Van;Bazairi, Hocein;Cocquyt, Christine	Nzigire, Elysée Rutakaza, Steenberge, Maarten Van, Bazairi, Hocein, Cocquyt, Christine (2026): Observations of Afrocymbella Krammer (Cymbellales, Bacillariophyta) in the guts of the cichlid fish Oreochromis leucostictus (Trewavas, 1933) from the Edward-George system, East Africa, with the description of a new species. European Journal of Taxonomy 1048: 111-141, DOI: 10.5852/ejt.2026.1048.3241, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3241/14353
