taxonID	type	description	language	source
03908795FFE64B05FCA98A81DCA7FC34.taxon	description	Results from our phylogenetic analyses found Proconvoluta primitiva clearly nested in the Faerlea clade as sister to the new species Faerlea assembli (Fig. 1). Dörjes (1968) separated Proconvoluta from Faerlea based on the seminal bursa, which is present in Proconvoluta, although small and difficult to distinguish in live specimens, and absent in species of Faerlea. Otherwise, the morphologies of the two genera generally overlap, in particular with the absence of rhabdoid glands and the heavily vacuolated parenchyma. Proconvoluta primitiva is the only species currently recognized for the genus, and so, based on the results of the phylogenetic analyses, Proconvoluta becomes a junior synonym of Faerlea.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFE64B05FC038F00DC2CF927.taxon	description	Marine, free-living or parasitic; seven species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFE64B05FC038F00DC2CF927.taxon	description	• Faerlea tyleri sp. nov.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFE64B07FC2D8DDCDBC9FA6F.taxon	description	Z o o b a n k r e g i s t r a t i o n: u r n: l s i d: z o o b a n k. org: act: C 46 A 5 FAF-F 9 E 0 - 4 C 44 - 8 B 5 C-D 69 CD 8 CD 46 EC Material examined: Holotype (SMNH-Type- 9334) and paratypes (SMNH-Type- 9335): serially sectioned specimens. Digital video and photographs of original specimens. Ty p e l o c a l i t y: S PA I N. M u t r i k u, S i e t e P l ay a s. 43 ° 19 ’ 41.5 ” N, 2 ° 22 ’ 46.7 ” W Habitat: Marine sediments. Subtidal, medium sand. Diagnosis: Species of Faerlea without pigmentation, glassy. Body 0.8 mm long, vermiform with rounded anterior and posterior. Large vacuoles in posterior. Smaller vacuoles present laterally and in the anterior. Frontal glands large. Rhabdoids absent. Testes and ovaries paired. Male system with round seminal vesicle, small antrum. Penis a simple inpocketing of the epidermis. Female system with bursa with a single small, ventrofrontally directed appendage. Gonopores separate. Etymology: This species is named after the Assemble Plus programme, funded by the European Community, which has supported a variety of marine field studies. Description Living specimens approximately 0.8 mm long. Width ~ 50 µm at position of stylet and slightly increasing toward posterior; ~ 75 µm at position of largest egg. Body shape vermiform with rounded anterior and posterior ends. Without body pigmentation or eyespots. Glassy in appearance. Statocyst 10 – 12 µm in diameter located ~ 50 µm from anterior end. Frontal organ present and large. Two large vacuoles present at the posterior end; smaller vacuoles present laterally and in the anterior, though more numerous in the posterior body. Epidermis 4 µm thick, uniformly covered with cilia. Cilia ~ 4 µm long. Rhabdoids absent. Mouth located at the secondquarter of the body, 15 µm long in fixed specimens. Ovaries paired. Female pore clearly separate from male pore, ciliated, opening ventral, ~ 9 µm long. Female atrium present, ~ 11 µm deep in fixed specimens leading to a short vagina and bursa. Bursa present 75 µm from posterior end, 28 µm long and 34 µm wide, with a single ventrofrontally directed cellular appendix. Sperm was not observed in the bursa of any specimen examined. Testes paired, located laterally approximately onequarter of the way from the anterior end of the body. Vas deferens large and clearly evident toward male copulatory organ, with evident sperm. Male copulatory organ present ~ 45 µm from posterior end, spheroid, ~ 35 µm long and ~ 30 µm wide in living specimens. Penis present as a simple inpocketing of the epidermis, 17 µm in fixed specimens, with a shallow male atrium. Male pore large, 15 µm long, ciliated. Remarks There are seven species of Faerlea, following the synonymization of Proconvoluta and Faerlea. Faerlea assembli is most similar to Faerlea primitiva in that they both possess a bursa with a ventrofrontally directed cellular appendage. The two species can be distinguished by the size of the bursa and male copulatory organ, which are more clearly evident and larger in Faerlea assembli, and through the small, brownish-black pigments that are present in Faerlea primitiva and absent in the new species.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFE44B09FC5D8ED4DA8EFC2C.taxon	description	(FIG. 4) Z o o b a n k r e g i s t r a t i o n: u r n: l s i d: z o o b a n k. org: act: D 7 ACB 50 A- 70 AB- 40 E 3 - ADB 7 - 86310945 FB 0 F Material examined: Holotype (SMNH-Type- 9336) and paratypes (SMNH-Type- 9337): serially sectioned specimens. Digital video and photographs of original specimens. Type locality: USA, Hawaii, Waimanolo Beach. 21 ° 19 ’ 8.23 ” N, 157 ° 40 ’ 11.92 ” W. Habitat: Marine sediments; mixed fine and medium sand with some organic content; 1.5 m deep. Diagnosis: Species of Faerlea without pigmentation, glassy. Body up to 1 mm long, vermiform with rounded anterior and posterior. Large vacuoles in posterior and laterally. Smaller vacuoles in the anterior. Frontal glands well developed. Rhabdoids absent. Testes and ovaries paired. Male copulatory organ located close the posterior end. Small, round seminal vesicle present with a penis as a simple inpocketing of the epidermis. Bursa or female accessory organs absent. Etymology: This species is named after Seth Tyler in recognition of his contributions to the taxonomy of Acoela. Description Living specimens up to 1 mm long. Glassy and without body pigmentation or eyespots. Body width ~ 67 µm at position of stylet and increasing toward posterior; ~ 100 µm at position of largest egg. Body shape vermiform with rounded anterior and posterior ends. Statocyst to 8 µm in diameter located 67 µm from anterior end. Frontal organ well developed. Large vacuoles present at the posterior end and extending laterally, decreasing in size toward the anterior; smaller vacuoles present in the anterior. Epidermis 4 – 5 µm thick, uniformly covered with cilia. Cilia 3 – 5 µm long. Rhabdoids absent. Mouth located at the second-quarter of the body. Ovaries paired, located in third-quarter of the body. Bursa or female accessory organs absent. Testes paired, located laterally approximately ~ 300 µm from the anterior end the body. Vas deferens more evident toward male copulatory organ, with clear sperm. Male copulatory organ small, ~ 20 µm long and ~ 25 µm deep in fixed specimens, spheroid. Present 55 µm from posterior end in living specimens. Penis present as a simple inpocketing of the epidermis, 9 µm long and projecting outward in fixed specimens. Male pore small, ~ 5 µm long, ciliated. Remarks Faerlea tyleri is the first species of its genus to be documented from Hawaii or the Pacific. In general, the species fits well with the other known species of Faerlea: Faerlea tyleri is fragile due to its heavily vacuolated parenchyma; the position of the testes is far toward the anterior; and the position and composition of the male copulatory organ is consistent with the other species. The species is most similar to F. fragilis and F. glomerata in that it is non-parasitic and does not possess female accessory organs. However, Faerlea tyleri differs from either species in its general body shape, which is more strap-shaped with rounded anterior and posterior ends than either F. fragilis or F. glomerata, and the small size of the male copulatory organ. Additionally, Faerlea tyleri can be distinguished from F. glomerata by the size of the frontal organ, which, although well developed, is smaller in comparison, the more distinctly paired ovaries and wide separation between the ovaries and the male copulatory organ. Faerlea tyleri can be distinguished from F. fragilis by the relatively few vacuoles and the position of the ovaries, which begin further toward the posterior end.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFEA4B09FCA98BF1DCE8FA05.taxon	description	There were several inconsistencies in Faubel & Regier’s (1983) original description of Alluna. First, they stated in the genus diagnosis that A. sublittoralis Faubel & Regier, 1983 was the type and only species, but entitled Alluna vulgaris as the caption of their illustrations. Since no other species description occurred apart from that of A. sublitoralis, and no illustration of A. sublitoralis was provided, Alluna vulgaris can be considered a synonym of Alluna sublitoralis. More importantly, Faubel & Regier (1983) stated in the diagnosis of Alluna that a true seminal vesicle is absent, but they described paired false seminal vesicles attached to a (true) seminal vesicle in the subsequent description of A. sublitoralis, a feature that was also clearly present in the following illustrations. If the genus diagnosis is thus emended to fit its type and only species, its morphology becomes more consistent with species of Actinoposthiidae than with Isodiametridae. Following the family diagnosis of Hooge (2001), Actinoposthiidae includes those species of Acoela with a penis built of either sclerotized or muscular elements that is never invaginated into a seminal vesicle. Alternately and according to the diagnosis of Hooge & Tyler (2005), Isodiametridae includes those species of Acoela with a muscular, isodiametric penis that is partially or completely invaginated into a muscular seminal vesicle, if present. The penis of Alluna sublitoralis is highly muscular, not isodiametric (following the original illustrations, the proximal part of the penis swells to form a bulb), and – different to all other species of Isodiametridae – lies entirely outside of the seminal vesicle. Unfortunately, sequences of Alluna sublitoralis are currently not available for analysis, so the position of the species could not be tested using molecular techniques. However, in consideration of its morphology, the species and genus must be transferred to Actinoposthiidae.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFEA4B0AFCA78EDFDA5FFCA8.taxon	description	Dörjes (1968) placed the three species of Baltalimania of the time into different genera, based solely on the presence or absence of a female bursa. Archaphanostoma was created to encompass two species [A. agile (Jensen, 1878) and A. macrospiriferum (Westblad, 1946)] with bursal tissue, leaving the one species that lacked bursal tissue (B. kosswigi Dörjes, 1968) to comprise its own monotypic genus. Subsequently and without mention of Baltalimania, Kånneby et al. (2014) amended the diagnosis of Archaphanostoma to include both species with and without bursal tissue, following phylogenetic analysis of nucleotide sequences from three genes that demonstrated that four new species without bursa (A. fontaneti Kånneby et al., 2015; A. occulta Kånneby et al., 2015; A. sublitorialis Kånneby et al., 2015 and A. ylvae Kånneby et al., 2015) nested within the Archaphanostoma clade. Unfortunately, the amended diagnosis caused Baltalimania and Archaphanstoma to be morphologically indistinguishable. Phylogenetic analyses oppose Dörjes’ (1968) argument that bursal tissue is a good character to differentiate these genera (Figs 1, 5). Although no DNA sequences currently exist for B. kosswigi, the identical generic diagnoses and similarities in the morphologies of B. kosswigi and species of Archaphanostoma without bursal tissue strongly suggest that the two genera are synonymous. Therefore, Archaphanostoma is a junior synonym for Baltalimania.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFEA4B09FF0B88F6D8BEF8F7.taxon	description	Both species of Postaphanostoma included in our analyses, P. glandulosum Dörjes 1968 and P. nilssoni Kånneby & Jondelius, 2013, grouped together as the highly supported sister-group of Mecynostomidae, separate from Isodiametridae. As with Faerlea, once again there has not been any detailed investigation into the body and reproductive musculature or sperm ultrastructure for any species of Postaphanostoma, and so it cannot be definitively stated if the animals of this group possess any of the morphological characteristics of Isodiametridae, Mecynostomidae or any other group. Indeed, the position of P. glandulosum and P. nilssoni as sister of Mecynostomidae in our phylogenetic analyses suggests such detailed morphological investigations should be of high priority for future studies. Unfortunately, no gene sequences of the type species of Postaphanostoma, P. atriomagnum Dörjes, 1968, currently exist. However, there are also no significant morphological characters that distinguish P. glandulosum and P. nilssoni from the remainder of the genus with which to justify a separation, and so, rather than create confusion by forming a new genus in which to transfer the two species, we choose to reassign Postaphanostoma in its entirety to Mecynostomidae until such time as sequences or more detailed morphology can be assessed for the type.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFE94B0CFCCB8BF1DADCFEDF.taxon	description	Dörjes (1968) placed great emphasis on the presence and structure of the bursa in his classification system, and numerous genera were created or separated based on small differences of this organ. When Dörjes (1968) described the species Bursosaphia baltalimaniaformis Dörjes, 1968, he justified the creation of a new genus based on what he interpreted as bursal tissue (‘ bursales Gewebe ’) in which the true bursa was embedded. However, Dörjes (1968) was somewhat unclear in his description of the bursal tissue that surrounds the female system, stating only that it is a tissue that stores foreign sperm, that it is separate from the parenchyma of the rest of the body and that it similarly is present in species of Archaphanstoma (= Baltalimania), which otherwise lack a true bursa. Dörjes (1968) also stated that bursal tissue may occur in other genera, but will typically disappear after a true bursa has formed. Unfortunately, this character has not been assessed for any species with a true bursa in any of the literature outside Dörjes’ (1968) description of Bursosaphia and, therefore, it is unclear how prevalent it is within Isodiametridae. Unfortunately, no sequences of B. baltalimaniaformis are currently available, and so the relationship between this species and other acoels cannot be directly tested at this time. Regardless, results from our phylogenetic analyses suggest that bursal tissue is not a good character for distinguishing genera, since the only species other than B. baltalimaniaformis known to possess it – Baltalimania macrospiriferum and B. agile – do not on their own form a clade, but instead group with species of Baltalimania without bursal tissue (Fig. 1). Given these results, and that there is no difference in the morphology of Bursosaphia and Praeaphanostoma apart from the bursal tissue, we propose to synonymize the two genera, with Bursosaphia the junior synonym for Praeaphanostoma. REASSIGNMENT OF HAPLOGONARIA SCHILLINGI HOOGE & TYLER, 2015 TO THE GENUS PRAEAPHANOSTOMA DÖRJES, 1968 Our results show Haplogonaria schillingi to be nested in Praeaphanstoma and closely related to Praeaphanostoma rubrum. Sequences of the 18 S, 28 S and COI genes were published for H. schillingi and used in several phylogenetic analyses before the species was formally described. Jondelius et al. (2011) found the species (denoted there as Haplogonaria ‘ schillingi ’) positioned closely to Pseudaphanostoma smithrii and transferred the species to Pseudaphanostoma on this basis. Later, Nilsson et al. (2011) and Kånneby & Jondelius (2013) used the sequences in their phylogenetic analyses with results congruent to Jondelius et al. (2011), but still listing the species as Haplogonaria schillingi. Of note, at the time of all three publications, no sequences of any species of Praeaphanstoma were available and, indeed, results from our analysis show that P. smithrii is the closest sister to all other species of Praeaphanstoma. Hooge & Tyler (2015) eventually described the species, but found that the male copulatory organ lacks a muscular, tubular penis. Because such morphology is incongruous with the diagnostic character of Isodiametridae, Hooge & Tyler (2015) dubbed the species Haplogonaria schillingi and assumed the molecular data resulted from an error in handling specimens. Our results, with the additional sequence data of Praeaphanstoma longum and especially P. rubrum, contradict the assertion that the position of H. schillingi in the phylogenetic analyses was due to some error. The morphology of H. schillingi is generally consistent with species of Praeaphanostoma. Praeaphanostoma is in part characterized by a moderate to small frontal organ, a muscular seminal vesicle, a seminal bursa with well-defined walls but without nozzles and a welldefined vagina with a sphincter, all characters that H. schillingi also possesses. Praeaphanostoma longum is additionally morphologically similar to H. shillingi in the shared possession of an unpaired ovary, common gonopore, diagonal muscles restricted to the anterior end and a characteristic bright-red pigmentation. The two species differ only in the size of the rhabdoids (small in P. longum, large in H. schillingi), possession of a genital atrium (absent in P. longum, present in H. schillingi) and, of course, the penis (present in P. longum, absent in H. schillingi). Given such similarities, the position of H. schillingi is conceivable, and the absence of a penis could potentially represent a secondary loss. Praeaphanostoma includes several species – including those in our analysis that were the closest to H. schillingi – where the penis is a simple inpocketing of the epidermis, a condition that in Isodiametridae is only otherwise present in Proaphanostoma. Thus, based on the positioning of the species in our phylogenetic analyses and the morphological similarity, we formally reassign Haplogonaria schillingi to Praeaphanostoma in Isodiametridae. REDESCRIPTION OF PSEUDAPHANOSTOMA HYALINORHABDOIDA KÅNNEBY & JONDELIUS, 2013 AND REASSIGNMENT TO PRAEAPHANOSTOMA DÖRJES, 1968 Following a re-examination of the original collection notes and materials, it is clear from both photographs of live animals and from fixed, sectioned animals that Kånneby & Jondelius (2013) incorrectly interpreted the morphology of the reproductive system of Pseudaphanostoma hyalinorhabdoida in their original description. The female bursa was described as the seminal vesicle; the actual seminal vesicle and connecting vas deferens were dismissed as patches of free sperm outside the male copulatory organ, and the penis was not identified. Kånneby & Jondelius (2013) based the inclusion of the species in Pseudaphanostoma on the mistaken lack of female accessory organs and the relationship between this species and Pseudaphanostoma smithrii in their phylogenetic tree. It is clear that this species does possess a female bursa, ciliated vagina and gonopore common to both the male and female system (Figs 6 – 7). The presence of an unadorned female bursa is a characteristic of species of Praeaphanostoma, while species of Pseudaphanostoma lack all female accessory organs. Further, results from our DNA analyses confirm a close relationship between this species with Praeaphanostoma longum and P. rubrum (Fig. 1), neither of which had sequences available when Kånneby & Jondelius (2013) performed their analysis. The morphological inaccuracies of the original description require that the species be redescribed, and the updated morphology and phylogenetic relationships support the transference of the species from Pseudaphanostoma to Praeaphanstoma.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFED4B0EFF328BF1D9E7F9A1.taxon	description	Kozloff (2000) proposed the genus Ancylocirrus after finding secretory granules in the lumen of the cirrus and in the vagina of its one species, A. ornatus Kozloff, 2000. The only details presented about these granules were that they were colourless, ~ 3 – 5 µm in diameter and likely secreted by the male system, since they were associated with sperm masses and present in the female system only after insemination. Kozloff (2000) stated that such secreted granules had not been reported in any other genera at the time and was thus sufficient for the establishment of a new genus. Sequence data is not available for Ancylocirrus ornatus at this time. However, while secretory granules such as those described by Kozloff (2000) may not be a character that has typically been assessed in the past (although, see e. g. Aphanostoma album Dörjes, 1968; Baltalimania histobursalium; Diatomovora amoena Kozloff, 1965), we can confirm that it is present across multiple species of Acoela (Fig. 8), including in at least one species of Praeaphanostoma (P. rubrum; Fig. 8 D). Further, based on our own personal observations, we hypothesize that far from being unique to one species, such secretions are probably common, especially in species with larger and more glandular male copulatory organs, such as can be found in species of, for example, Baltalimania (Fig. 8 B, C). Ancylocirrus is further characterized by the morphology of the reproductive system: a long, curved cirrus invaginated into a seminal vesicle; a small, unciliated antrum masculinum; a long, muscular vagina; and, finally, a conspicuous seminal bursa without adornment. This morphology, along with the general body shape and pigmentation, fits in its entirety with species of Praeaphanostoma. While Ancylocirrus ornatus does differ in that it has pigmented eyespots, genera with species both with and without eyespots are widespread throughout Acoela (e. g. Amphiscolops Graff, 1904; Isodiametra; Nadina Ulajnin, 1870; Otocelis; Proporus Schmidt, 1848) and the character is unlikely to be of much taxonomic importance. Thereby, Ancylocirrus is designated a junior synonym of Praeaphanostoma.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF24B11FE8288D5DB08FD2C.taxon	description	Marine, free-living, 16 species: • Aphanostoma virescens Ørsted, 1845	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF24B11FC4289D4DCB5FB15.taxon	description	Marine, free-living or parasitic; six species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF14B12FED48ADAD882FADC.taxon	description	Marine, free-living; nine species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF14B12FED48ADAD882FADC.taxon	description	• Baltalimania sublittoralis (Kånneby et al., 2015), comb. nov. • Baltalimania ylvae (Kånneby et al., 2015), comb. nov.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF14B12FEB38EE0DAF4F8DF.taxon	description	Marine, free-lining; two species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF14B12FC4C88F1DCC9FB5C.taxon	description	Marine, free-lining; one species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF14B13FCA28D9BDAEEFF51.taxon	description	Two other species of Isodiametridae have a pharynx (Isodiametra helgolandica and Praeaphanstoma longum). Species of Pharyngia can be separated from both based on the absence of a seminal bursa.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF14B12FC378EB5DCC9F93E.taxon	description	Marine, free-lining; one species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF04B13FE998A02DA8CFAF2.taxon	description	Marine, free-lining; 16 species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF04B13FE898EA9DBBAFC11.taxon	description	Marine, free-living; 17 species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF04B13FC0788CDDCDCFA80.taxon	description	Marine, free living; one species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF04B14FCE78EB9DA9CFEDF.taxon	description	Marine, free-lining; eight species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF74B14FE8D8A91DA57FCBF.taxon	description	Marine, free-living; one species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF74B14FC788BF0DCC9FE72.taxon	description	Marine, free-lining; one species:	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
03908795FFF74B15FCA28AC7DA8EFDA5.taxon	description	Rimicola can be distinguished from most of the other genera of Isodiametridae by the absence of rhabdoid glands, a muscular seminal vesicle a n d f e m a l e a c c e s s o r y o r g a n s. I t i s c l o s e s t i n morphology to Pseudoposthia, which also lacks a true seminal vesicle and bursa, but Pseudoposthia can be differentiated through the absence of an antrum masculinum and the presence of rhabdoids and a glandular organ associated with the male copulatory organ. Rimicola is also similar in morphology to other species of Faerlea (Mecynostomidae). Species of both lack rhabdoids and a seminal bursa and have a small antrum masculinum. Unlike Rimicola, species of Faerlea are characterized, among other things, by a short penis with associated glands and a muscular seminal vesicle. Further investigation, including obtaining DNA sequences, is needed to assess the position of the genus within Isodiametridae and Acoela.	en	Atherton, Sarah, Jondelius, Ulf (2022): Phylogenetic assessment and systematic revision of the acoel family Isodiametridae. Zoological Journal of the Linnean Society 194: 736-760, DOI: 10.1093/zoolinnean/zlab050
