Despite the long research history on the genus Coelastrella, its species diversity and biotechnological potential have not been fully explored. For the first time, cluster analysis of morphological characteristics was done in the representatives of the said genus. The results obtained have shown that morphological similarity does not necessarily indicate a molecular genetic relationship. It the light of it, the taxonomic status of species can reliably be determined using specific DNA region, such as 18S-ITS1-5.8S-ITS2. The V4 and V9 regions of gene 18S rRNA are relatively conservative fragments which are not suitable for species identification. The ITS2 can be used as a \"short barcode\". Among the advanced machine methods for delimitation species, the most effective algorithm for distinguishing Coelastrella species was the Generalized Mixed Yule Coalescent (GMYC) method. This paper represented for the first time our comprehensive review of the works devoted to the analysis of the biotechnological potential of representatives of the genus Coelastrella and shows that fatty acid composition of the three main chemogroups within the studied genus differs. In the future, this may form the basis for predicting the composition of the fatty acid profile of new strains, which is important while searching for organisms with specified biotechnological properties. In conclusion, an integrative approach was employed to describe Coelastrella affinis sp. nov., a new species of the genus Coelastrella with high biotechnological potential. Also, a new description of C. thermophila var. astaxanthina comb. nov. was proposed.

Desmodesmus spp. are one of the most dominant components of phytoplankton, which are present in most water bodies. However, identification of the species based only on morphological data is challenging. The aim of the present study was to provide a comprehensive understanding of the actual distribution of the Desmodesmus species in Saga City, Saga Prefecture, Japan. In the present study, 38 water bodies were surveyed between June 2017 and March 2023. A total of 86 culture strains were established from the samples collected from the 21 sites, and identified by molecular phylogenetic analysis, comparison of ITS2 rRNA secondary structures, and observation of surface microstructure. In total, four new species, including D. notatus Demura sp. nov., D. lamellatus Demura sp. nov., D. fragilis Demura sp. nov., and D. reticulatus Demura sp. nov. were proposed and 17 Desmodesmus species were identified as described species. The present study revealed > 20 Desmodesmus species, exhibiting high genetic diversity in a small area.

Taxonomic notes, together with illustrated characters, on the oriental species of the genus Macrocheilus Hope, 1838 (Carabidae, Helluonini) are provided. One new species, Macrocheilus deuvie sp. n. is described from the Philippines. A key to all species of Macrocheilus in the Oriental Region is also provided.

Five new species of the Macrolycusligulatus species-group, M.expansus sp. nov., M.quartus sp. nov., M.costus sp. nov., M.opacipennis sp. nov. and M.curtus sp. nov., are reported from China and described with macrophotographs of the habitus of both sexes and aedeagi. Macrolycusguangxiensis Li, Bocak & Pang, 2015 is illustrated showing the female habitus and genitalia for the first time. In addition, a distribution map and a key to all species of the M.ligulatus species-group are provided.

UNASSIGNED: Pseudopoda Jäger, 2000 is currently the largest genus in the family Sparassidae Bertkau, 1872, comprising 255 species. Of these, 154 species have been recorded in China, representing 60.4% of the global species.In October 2023, a spider survey was conducted in Shennongjia National Nature Reserve, Hubei Province, China. After examination and morphological comparison, one new species of the genus Pseudopoda was identified and is described here.
UNASSIGNED: In this paper, a new species of Pseudopoda collected in Hubei Province, China, is proposed and named Pseudopodaguanmenshan sp. nov. A detailed description, diagnosis, photographs and distribution map of the new species are provided.

Stauroneis (Naviculales, Bacillariaceae) are widespread, mostly in fresh-water habitats, and account for 343 species. They are described mainly on the basis of morphology and morphometric traits. These characteristics vary during life cycles and may overlap between species, making their identification difficult. We isolated two strains of naviculoid diatoms and examined them using an integrative approach (phylogenetic, morphological, ultrastructural data, and life cycle). Phylogenetic analyses based on chloroplast rbcL gene data showed affinity of the new strains to the genus Stauroneis. Our algae share morphological features typical of Stauroneis but differ from similar species in minimal valve length measurements, valve apex shape, and minimal number of striae in 10 μm. Two strains are distinct from each other in maximal valve length and width, partially valve shape, the number of areolae in 10 μm, and cingulum structure. It was revealed that the strains reproduce via isogamy. Three species delimitation methods (ASAP, PTP, and GMYC) also confirmed that the two closely related new strains represent distinct species. Based on molecular data and phenotypic traits examined within the framework of an integrative approach, we describe two new isolates as Stauroneis urbani sp. nov. and Stauroneis edaphica sp. nov.

The new genus, Cerogamasus gen. nov., with the type species Cerogamasus tibetensis sp. nov., is established. The new genus is easily distinguished from other genera of Parasitidae because the dorsal idiosoma in both sexes bears more than 40 pairs of setae, of which fewer than 7 pairs of podonotal setae are smooth; the seta z5 of the dorsal hexagon is similar to j5 and j6 in form (pilose or distally pilose) while different in length (z5 longer); the seta al of the palpfemur is pectinate, and al1 and al2 of the palpgenu are entire; the gnathotectum is trispinate; peritrematal shields in females are posteriorly free; and the palptrochanter in males has a pointed ventral protuberance. C. anhuiensis sp. nov., C. guizhouensis sp. nov. and C. multidentatus sp. nov. are described based on adult samples; C. tibetensis sp. nov. is described based on deutonymph and adult samples. Cycetogamasus coreanus Athias-Henriot, 1980, is transferred to Cerogamasus gen. nov. as a new combination.

Quill mites of the family Syringophilidae are widely distributed parasites of birds inhabiting the interior of feather quills. In this paper, we provide detailed information on the host spectrum and distribution for six previously described species of syringophilines associated with starlings with new host and locality records. Additionally, we describe three new species: Aulonastus indonesianus Marcisova, Skoracki, and Patan sp. n. from the Common Hill Myna Gracula religiosa Linnaeus in Indonesia (Java) and the White-necked Myna Streptocitta albicollis (Vieillot) in Indonesia (Celebes); Aulonastus anais Skoracki and Patan sp. n. from the Golden Myna Mino anais (Lesson) in Papua New Guinea; and Syringophiloidus poeopterus Skoracki and Patan sp. n. from the Abbott\'s Starling Poeoptera femoralis (Richmond) in Tanzania. Finally, we explore the host-parasite interactions within the system comprising starlings and syringophiline mites.

Galactosomum nagasakiense n. sp. (Digenea: Heterophyidae), the causative parasite of trematode whirling disease of marine fish, is described, based on the specimens collected from the black-tailed gull, Larus crassirostris in Nagasaki Prefecture, Japan. The new species belongs to the cochleariformum group, and is different from the three species in the group: G. cochleare (Diesing, 1850) in the larger oral sucker and phaynx and smaller eggs, G. cochleariformum (Rudolphi, 1819) in the smaller oral sucker and pharynx and smaller eggs, and G. spinetum (Braun, 1901) in the uterus which extends anterior to the ventrogenital sac. Metacercariae collected from the brain of several marine fish developing trematode whirling disease are also described. Considering low host specificity of the second intermediate hosts, the endemic nature of the trematode whirling disease may be attributed to the infection of a particular population of the final host and/or a limited geographical distribution of the first intermediate host.

OBJECTIVE: This paper aims to describe Plenivitellinum kifi n. gen., n. sp. (Digenea: Azygiidae) infecting the gastrointestinal tract of the African tigerfish, Hydrocynus vittatus Castelnau, 1861 (Characiformes: Alestidae) in the Kavango River, Namibia. We revise the diagnosis of Azygiidae Lühe, 1909 to accommodate this new species.
METHODS: The worm was heat-killed, fixed in 10% neutral buffered formalin, stained in Van Cleave\'s and Ehrlich\'s hematoxylins, cleared in clove oil, and mounted on glass slide using Canada balsam.
RESULTS: The new azygiid resembles species of Otodistomum Stafford, 1904 by having an elongate body, a ventral sucker that is wider than the oral sucker and that is in the anterior half of the body, a pre-testicular ovary, a uterus that primarily occupies the inter-caecal space between the ovary and the ventral sucker, and a vitellarium that is restricted to the hindbody and that is confluent posteriorly in the post-testicular region. The new genus differs from all species of Azygiidae by having the combination of a ventral sucker that is wider than the oral sucker (vs. narrower), an elongate prostatic sac that extends posteriad to near the posterior margin of the ventral sucker (vs. an ovoid prostatic sac that is wholly anterior to or slightly overlaps the anterior margin of the ventral sucker), a vitellarium that nearly fills the post-testicular space and that extends posteriad beyond the caecal tips (vs. a vitellarium that is separate posteriorly or that is restricted to the anterior half of the post-testicular space and does not extend posteriad beyond the caecal tips), and an I-shaped excretory bladder (vs. Y-shaped).
CONCLUSIONS: This study documents the first record of an azygiid from Africa and the first record of an azygiid infecting a characiform fish.