identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
CF6B87F3E6388511FF6FFA99FD3EFE3C.text	CF6B87F3E6388511FF6FFA99FD3EFE3C.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Baltalimania asinariensis Atherton & Jondelius 2022	<div><p>Baltalimania asinariensis sp. nov.</p> <p>Figures 3</p> <p>Zoobank registration. urn:lsid:zoobank.org:act: A12B4C50-5E92-4CDF-B49D-748479A4DE01</p> <p>Materials examined. Digital video and photographs of original living specimen, Holotype (SMNH Type-9424)</p> <p>Type locality. <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=8.284167&amp;materialsCitation.latitude=41.06472" title="Search Plazi for locations around (long 8.284167/lat 41.06472)">Cala Stagno Lungo</a>, Asinara Island, Italy, 41°03’53 N, 8°17’03 E</p> <p>Habitat. 0.3–1 m depth, marine, medium sand.</p> <p>Diagnosis. Body length 0.4–0.6 mm. Body clear and without pigmentation. Frontal organ small. Rhabdoid glands in longitudinal rows. Posterior vacuole present. Paired testes and ovaries. Seminal bursa present just posterior to largest egg. Male copulatory organ large, with penis partially invaginated into the seminal vesicle. Penis 17–20 µm long, curved. Antrum masculinum small, ciliated. Male gonopore subterminal.</p> <p>Etymology. This species is named for its type locality, Asinara Island.</p> <p>Description. Living specimen 0.45–0.60 mm long and to 0.12 mm width at midpoint. Free-swimming specimens lively and quick. Elongate with rounded anterior and posterior ends. Body colorless, without pigmentation and clear. Numerous lipid droplets of varying sizes present in digestive parenchyma and throughout the body, clear to yellow in color. Digestive parenchyma extends from just posterior of statocyst to level of posterior egg. Mouth not observed.</p> <p>Frontal organ small, just reaching level of statocyst. Statocyst present 70 µm from anterior end, 10–12 µm in diameter with 6–7 µm statolith. Posterior vacuole present.</p> <p>Epidermis completely ciliated. Cilia 4–6 µm long. Rhabdoid glands clearly distributed in longitudinal rows. Rhabdoid glands partially subepidermal, colorless, 6 µm in length.</p> <p>Ovaries and testes paired. Small seminal bursa present, located just below largest egg and typically with sperm. Bursa indistinct without walls or ornamentation, globular, 26–30 µm long and 16–18 µm wide. Separate female gonopore present at ventral midline ~70 µm from posterior end of animal.</p> <p>Male copulatory organ large, 39–40 µm long and 36–36 µm wide. Globular. Penis invaginated into the seminal vesicle and extending into the antrum masculinum. Isodiametric penis curved, 17–20 µm long. Antrum masculinum short, ciliated. Male gonopore at ventral midline.</p></div> 	http://treatment.plazi.org/id/CF6B87F3E6388511FF6FFA99FD3EFE3C	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E63C851EFF6FFDA8FF76FC95.text	CF6B87F3E63C851EFF6FFDA8FF76FC95.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Baltalimania salinsula Atherton & Jondelius 2022	<div><p>Baltalimania salinsula sp. nov.</p> <p>Figure 4</p> <p>Zoobank registration. urn:lsid:zoobank.org:act: 7464785C-58B6-499C-BDCA-BEF48B373812</p> <p>Materials examined. Digital video and photographs of original living specimen, Holotype (SMNH Type-9425)</p> <p>Type locality. Saltö Badstrand, Strömstad, Sweden; 58°52’41 N, 11°06’56 E</p> <p>Habitat. 2 m depth, marine, medium sand</p> <p>Diagnosis. Body length 0.85 mm. Body pigmentation absent. Frontal organ small. Rhabdoid glands distributed in longitudinal rows. Vacuoles absent. Paired testes and ovaries. Seminal bursa absent. Male copulatory organ with penis partially invaginated into the seminal bursa. Penis 27 µm long, curved. Male gonopore subterminal.</p> <p>Etymology. This species is named for its type locality, Saltö (Latin: sal salt; insula island)</p> <p>Description. Living specimen 0.85 mm long and to 0.18 mm maximum width. Free-swimming specimens elongate with rounded anterior end and pointed posterior. Body colorless, except for parenchyma, which is dark yellow or brown from food. Numerous lipid droplets of varying sizes present in digestive parenchyma and throughout the body, clear to yellow in color. Digestive parenchyma extends from just posterior of statocyst to posterior eggs. Mouth not observed.</p> <p>Frontal organ small, not extending to level of statocyst. Statocyst present 115 µm from anterior end, 15 µm in diameter with 11 µm statolith. Vacuoles absent.</p> <p>Epidermis completely ciliated. Cilia 6–7 µm long. Rhabdoid glands distributed in longitudinal rows. Posterior rhabdoid glands partially subepidermal, colorless, 8–10 µm in length.</p> <p>Ovaries and testes paired. Ovaries anterior to male copulatory organ, present in the posterior ~¼ of the animal. Seminal bursa absent. Vagina and female gonopore not observed.</p> <p>Male copulatory organ close to posterior end, globular with a width of 56 µm and a length of 52 µm. Penis partially invaginated into seminal vesicle. Penis small, 27 µm long, and curved. Male gonopore located at ventral midline.</p></div> 	http://treatment.plazi.org/id/CF6B87F3E63C851EFF6FFDA8FF76FC95	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E633851EFF6FFC4DFE3EF83C.text	CF6B87F3E633851EFF6FFC4DFE3EF83C.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Baltalimania microcurvum Atherton & Jondelius 2022	<div><p>Baltalimania microcurvum sp. nov.</p> <p>Figure 5</p> <p>Zoobank registration. urn:lsid:zoobank.org:act: 69575F0F-E9FA-412E-B902-F9D0E77C584D</p> <p>Materials examined. Digital video and photographs of original living specimens, Holotype (SMNH Type-9426) and Paratypes (SMNH Type-9427– SMNH Type-9431)</p> <p>Type locality. Saltö Badstrand, Strömstad, Sweden; 58°52’41 N, 11°06’56 E</p> <p>Habitat. 0.5–1 m depth, marine, medium sand</p> <p>Diagnosis. Body length 0.5–0.7 mm. Body colorless, without pigmentation. Frontal organ large. Rhabdoid glands sparsely distributed in longitudinal rows. Vacuoles absent. Paired testes, unpaired ovary. Seminal bursa present without ornamentation. Gonopores separate. Male copulatory organ with penis partially invaginated into the seminal vesicle. Penis 45 µm long, curved. Antrum masculinum unciliated. Male gonopore at ventral midline.</p> <p>Etymology. This species is named in reference to the small, curved penis that is the prevailing morphological character distinguishing it from B. macrospiriferum</p> <p>Description. Living specimen 0.5–0.7 mm in total body length and to 0.13 mm maximum width. Specimens in squeeze-preparation drop-shaped; free-swimming specimens more elongate with rounded anterior and posterior ends. Body colorless, transparent, except for parenchyma, which varies from green or yellowish-brown based on microalgae food. Lipid globules few, mostly smaller in size than statocyst. Mouth located approximately ¼ of the way from the anterior end. Digestive parenchyma extending from mouth to level of the largest, posteriormost egg. Mouth present at approximately ⅓ body length from the anterior end.</p> <p>Frontal organ large, extending posterior to statocyst. Statocyst present 70–80 µm from anterior end, 17–18 µm in diameter with 11–12 µm statolith. Epidermis completely ciliated and ~4 µm wide in longitudinal sections. Cilia 4–6 µm long. Rhabdoid glands relatively sparse, distributed in longitudinal rows. Posterior rhabdoid glands partially subepidermal, colorless, 9 µm in length.</p> <p>Ovary unpaired. Seminal bursa present just posterior to largest egg. Bursa elongate with evident sperm bundle. Bursa without distinct walls, approximately 30–35 µm long and to 45 µm (34–45) wide. Bursal nozzles and appendages absent. Short, unciliated vagina leading to separate female gonopore.</p> <p>Testes paired, located just anterior of the midbody. Male copulatory organ terminal in posterior end, spherical or globular with a width of 48–51 µm and a length of 44–45 µm. Penis partially invaginated into seminal vesicle, extending outward into the unciliated antrum masculinum. Penis slightly curved, 44–45 µm long. Male gonopore located at ventral midline.</p></div> 	http://treatment.plazi.org/id/CF6B87F3E633851EFF6FFC4DFE3EF83C	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E632851AFF6FF9F0FDE9FE93.text	CF6B87F3E632851AFF6FF9F0FDE9FE93.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Baltalimania arcuatum Atherton & Jondelius 2022	<div><p>Baltalimania arcuatum sp. nov.</p> <p>Figure 6, 7</p> <p>Zoobank registration. urn:lsid:zoobank.org:act: 85B18597-A6A7-4135-A0A3-10D2C7C9EC5E</p> <p>Materials examined. Serial sectioned specimen, Holotype (SMNH Type-9432); Digital video and photographs of original living specimens and serial sectioned specimens, Paratypes (SMNH Type-9433– SMNH Type-9452)</p> <p>Type locality. <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=-8.459694&amp;materialsCitation.latitude=37.09261" title="Search Plazi for locations around (long -8.459694/lat 37.09261)">Vale de Covo</a>, Carvoeiro, Portugal, 37°05’33.4 N 8°27’34.9 W</p> <p>Habitat. 1 m depth, marine, fine sand</p> <p>Diagnosis. Body length 0.5 mm. Body clear and without pigmentation. Frontal organ large. Rhabdoid glands numerous in clear longitudinal rows. Posterior vacuole present. Paired testes and unpaired ovary. Seminal bursa without distinct walls present with small, arched bursal nozzle. Male copulatory organ large, with penis partially invaginated into the seminal vesicle. Penis 30–40 µm long, sharply curved. Antrum masculinum large, unciliated. Male gonopore ventral.</p> <p>Etymology. This species is named in reference to the arched shape of the bursal nozzle (Latin: arcuatum arched).</p> <p>Description. Living specimen 0.5 mm long and to 0.09 mm at widest point. Animal broadest in the anterior at level of statocyst, width tapering towards the posterior. Anterior and posterior ends rounded. Body colorless, without pigmentation and clear. Numerous lipid droplets of varying sizes present in digestive parenchyma and throughout the body, clear to yellow in color. Digestive parenchyma extends from ~¼ body length from the anterior to level of the most posterior egg. Mouth present just anterior to midbody.</p> <p>Frontal organ large, extending past level of statocyst. Statocyst present 65 µm from anterior end, 10–11 µm in diameter with 6 µm statolith. Posterior vacuole present. Epidermis completely ciliated. Cilia 4–6 µm long. Rhabdoid glands numerous, distinctly distributed in longitudinal rows. Rhabdoid glands partially subepidermal, colorless, 6 µm in length.</p> <p>Ovary unpaired, often with numerous large eggs. Seminal bursa present with bursal nozzle. Bursa without distinct walls, ~45 µm long, typically with sperm present in the anterior near the nozzle. Bursal nozzle 7–8 µm wide, arching with thin lateral extensions. Vagina and female gonopore not observed.</p> <p>Testes paired, located ¼ body length from the anterior. Male copulatory organ large, 37–39 µm long and 42–44 µm wide. Globular. Penis partially invaginated into the seminal vesicle, with the tip extending into a large antrum masculinum. Penis sharply curved, “J” shaped, 30–40 µm long. Proximal end of penis surrounded by the prostatic vesicle. Antrum masculinum unciliated. Male gonopore ventral.</p> <p>Genus Praeaphanostoma DÖRJES 1968</p></div> 	http://treatment.plazi.org/id/CF6B87F3E632851AFF6FF9F0FDE9FE93	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E637851BFF6FFE6CFAB3FC24.text	CF6B87F3E637851BFF6FFE6CFAB3FC24.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Praeaphanostoma diatomovorum Atherton & Jondelius 2022	<div><p>Praeaphanostoma diatomovorum sp. nov.</p> <p>Figure 8</p> <p>Zoobank registration. urn:lsid:zoobank.org:act: 091F3968-6642-44CD-9799-37A65EFB701C</p> <p>Materials examined. Serial sectioned specimen, Holotype (SMNH Type-9453); Digital video and photographs of original living specimens and serial sectioned specimens, Paratypes (SMNH Type-9454– SMNH Type-9467).</p> <p>Type locality. <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=11.464444&amp;materialsCitation.latitude=58.25139" title="Search Plazi for locations around (long 11.464444/lat 58.25139)">Klubban</a> beach, Gullmarsfjorden, Sweden, 58°15’05 N, 11°27’52 E; <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=11.474444&amp;materialsCitation.latitude=58.25861" title="Search Plazi for locations around (long 11.474444/lat 58.25861)">Kvarnbukten</a>, Bohuslän, Sweden, 58°15’31 N, 11°28’28 E</p> <p>Habitat. 1–2.5 m depth, marine, silty sand with organic content; 1–1.5 m depth, medium sand</p> <p>Diagnosis. Body length 0.5–0.9 mm. Body pigmentation absent. Frontal organ moderate in size. Rhabdoid glands sparse in rows. Vacuoles absent. Testes paired; ovary unpaired. Seminal bursa present without ornamentation. Short vagina connects to common antrum and gonopore. Male copulatory organ subterminal without penis.</p> <p>Etymology. This species is named in reference to the numerous diatoms present in the digestive parenchyma of the type specimens.</p> <p>Description. Living specimen 0.5–0.9 mm in total body length depending on state of elongation and 0.12–0.2 mm in maximum width at point of largest egg. Specimens in squeeze-preparation drop-shaped; free-swimming specimens more elongate with rounded anterior and posterior ends. Body colorless, transparent, except for parenchyma, which varies from green or yellowish-brown based on microalgae food. Digestive parenchyma extends from ¼ body length from the anterior to level of posterior egg. Mouth present just past ¼ body length from anterior end, ~22 µm in width.</p> <p>Frontal organ extending from anterior end to just posterior to statocyst. Statocyst present 90–110 µm from anterior end, 11 µm in diameter with 8 µm in diameter statolith. Epidermis completely ciliated and ~4 µm wide in longitudinal sections. Cilia 4–6 µm long. Rhabdoid glands present in longitudinal rows, sparse and best visible at the posterior end. Posterior rhabdoids partially subepidermal, colorless, 9–10 µm in length.</p> <p>Ovary unpaired with up to four eggs. Seminal bursa present just posterior to largest egg. Bursa globular or eggshaped with narrower, tapering proximal part; width to 36 µm (24–36 µm) and length to 65 µm (46–65 µm). Bursa typically filled with evident sperm. Bursal nozzles or appendages absent. A short unciliated vagina connects the bursa ventrally to a common antrum and gonopore.</p> <p>Testes paired, located just posterior of the midbody and anterio-lateral to the ovary. Seminal vesicle subterminal in posterior end, spherical or globular with a width of 23–38 µm and a length of 25–38 µm. Penis absent.</p></div> 	http://treatment.plazi.org/id/CF6B87F3E637851BFF6FFE6CFAB3FC24	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E6368518FF6FFBDDFDCCF943.text	CF6B87F3E6368518FF6FFBDDFDCCF943.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Praeaphanostoma neglectum Atherton & Jondelius 2022	<div><p>Praeaphanostoma neglectum sp. nov.</p> <p>Figure 9</p> <p>Zoobank registration. urn:lsid:zoobank.org:act: 010B5C0C-78D2-4EF4-975D-F8D990526E8B</p> <p>Materials examined. Digital video and photographs of original living specimen, Holotype (SMNH Type-9468).</p> <p>Type locality. North of Ellenbogen, Sylt, Germany; 55°03’13 N, 8°27’24 E</p> <p>Habitat. 16 m depth, marine, medium sand</p> <p>Diagnosis. Animal short and wide, 0.6 mm body length and 0.23 mm width. Frontal organ small. Rhabdoid glands highly abundant in longitudinal rows. Unpaired ovary. Bursa present, simple without adornment. Male copulatory organ subterminal with evident small penis. Penis conical, 12 µm long. Vacuoles absent.</p> <p>Etymology: This species is named in reference to the more than ten years length of time between specimen collection and species description (Latin: neglectus neglected)</p> <p>Description. Living specimen 0.60–0.65 mm in total body length and 0.23 mm at the midpoint. Body shape elliptical with bluntly rounded anterior end and rounded posterior end. Body colorless, transparent, except for brown-orange parenchyma from food. Mouth located approximately ⅓ of the way from the anterior end. Digestive parenchyma extending to level of posterior egg.</p> <p>Frontal organ small, extending from the anterior end halfway to the statocyst. Statocyst present 125 µm from anterior end, 20 µm in diameter with 15 µm statolith. Epidermis uniformly ciliated. Cilia 8–10 µm long. Rhabdoid glands highly abundant in longitudinal rows, partially subepidermal across body, colorless, 6–9 µm in length.</p> <p>Ovary unpaired, with up to four eggs. Seminal bursa present just posterior to largest egg. Bursa elliptical with allosperm generally present in the anterior portion. Bursa width to 67 µm and length to 36 µm. Bursal nozzles or appendages absent. Female gonopore and vagina not observed.</p> <p>Testes paired, located midbody and just anterior to the ovary. Male copulatory organ subterminal in posterior end, roughly globular with a diameter of 48–50 µm. Penis invaginated into seminal vesicle and extending caudally, straight and gently conical. Penis length 12 µm, conical, width at the base 12 µm and at the tip 3 µm. Male gonopore present.</p> <p>Genus Pseudoposthia WESTBLAD 1946</p></div> 	http://treatment.plazi.org/id/CF6B87F3E6368518FF6FFBDDFDCCF943	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E6358506FF6FF956FB91FC6C.text	CF6B87F3E6358506FF6FF956FB91FC6C.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Pseudoposthia lata Atherton & Jondelius 2022	<div><p>Pseudoposthia lata sp. nov.</p> <p>Figure 10</p> <p>Zoobank registration. urn:lsid:zoobank.org:act: 70BAF94F-C846-4156-84FD-70B58301213A</p> <p>Materials examined. Serial sectioned specimen, Holotype (SMNH Type-9469); Digital video and photographs of original living specimens, Paratypes (SMNH Type-9470– SMNH Type-9480)</p> <p>Type locality. <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=11.220555&amp;materialsCitation.latitude=58.571667" title="Search Plazi for locations around (long 11.220555/lat 58.571667)">Getryggen</a>, Skaggerak, Sweden, 58°34’18 N, 11°13’14 E; <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=11.191667&amp;materialsCitation.latitude=58.56222" title="Search Plazi for locations around (long 11.191667/lat 58.56222)">Vedholmen-Hamnholmen</a>, Skaggerak, Sweden, 58°33’44 N, 11°11’30 E; <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=11.201388&amp;materialsCitation.latitude=58.585" title="Search Plazi for locations around (long 11.201388/lat 58.585)">Vrakholmen</a>, Skaggerak, Sweden, 58°35’06 N, 11°12’05 E; <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=10.990001&amp;materialsCitation.latitude=58.89778" title="Search Plazi for locations around (long 10.990001/lat 58.89778)">Basteviken</a>, Skaggerak, Sweden, 58°53’52 N, 10°59’24 E.</p> <p>Habitat. 6–10 m depth, medium to coarse sand with silt</p> <p>Diagnosis. Animal small and wide, 0.35–0.5 mm long and to 0.25 mm wide. Numerous large rhabdoid glands scattered across body. Vacuoles restricted to the posterior end. Ovaries and testes paired. Bursa absent. Unwalled false seminal vesicle leading to paired false seminal vesicles and paired testes. Male system located ventral to the ovaries and anterior to the largest egg. Gonopore large and distinct, surrounded by muscular sphincter. Penis absent.</p> <p>Etymology. This species is named in reference to the broad width relative to the length of the animal (Latin: lata broad)</p> <p>Description. Animal short and wide, body length 0.35–0.5 mm and width to 0.25 mm. Specimens in squeezepreparation drop-shaped with rounded ends. Anterior or midpoint broader relative to the posterior. Body colorless, transparent, except for parenchyma, which varies from bright green or yellowish-brown based on microalgae food. Mouth present approximately at body’s midpoint</p> <p>Frontal organ moderate, extending from anterior end to just posterior to statocyst. Statocyst present 65 µm from anterior end, 15 µm in diameter with 12 µm in diameter statolith. Epidermis completely ciliated and ~5 µm wide in longitudinal sections. Cilia ~6 µm long. Rhabdoid glands large, numerous and scattered across the body. Rhabdoids partially subepidermal, to 22 µm in length in living specimen.</p> <p>Paired ovaries with numerous eggs. Largest egg medial near the caudal end, just anterior to the posterior vacuoles. Seminal bursa, vagina and female gonopore absent.</p> <p>Male system present anterior of the largest egg. Central false seminal vesicle globular, to 45 µm (38–45 µm) in width, connecting laterally to paired false seminal vesicles and testes. False seminal vesicles lack walls and are non-muscular, comprising of a mass of sperm or possibly spermatophore. Testes located ~⅓ body length from the anterior end. Large and distinct gonopore present just anterior to the central false seminal vesicle, 34–35 µm wide and 18–20 µm long. Gonopore surrounded by muscular sphincter. Penis absent.</p></div> 	http://treatment.plazi.org/id/CF6B87F3E6358506FF6FF956FB91FC6C	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E62B8504FF6FFBE0FE48FE40.text	CF6B87F3E62B8504FF6FFBE0FE48FE40.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Pseudoposthia hanssoni Atherton & Jondelius 2022	<div><p>Pseudoposthia hanssoni sp. nov.</p> <p>Figure 11</p> <p>Zoobank registration. urn:lsid:zoobank.org:act: 0E41935C-E677-427A-BA6C-EB5683043453</p> <p>Materials examined. Digital video and photographs of original living specimens, Holotype (SMNH Type-9481) and Paratype (SMNH Type-9482).</p> <p>Type locality. <a href="http://tb.plazi.org/GgServer/search?materialsCitation.longitude=11.064445&amp;materialsCitation.latitude=58.581112" title="Search Plazi for locations around (long 11.064445/lat 58.581112)">Väderöarna</a> naturhamn, Skagerrak, Sweden, 58°34’52 N, 11°03’52 E</p> <p>Habitat. 4–6 m depth, coarse sand and rocks with some shell hash</p> <p>Diagnosis. Body length 0.45 mm long and to 0.15 mm wide in squeezed preparation. Frontal organ well-developed. Rhabdoid glands numerous and scattered. Several large vacuoles present in posterior half of the body. Ovaries and testes paired. Bursa absent. Unwalled false seminal vesicle located ventral to the ovaries and anterior to the largest egg, leading directly to the gonopore posterior to the penis. Glandular penis straight, 9–10 µm long. Gonopore large and distinct, surrounded by thick muscular sphincter.</p> <p>Etymology. This species is named in honor of the late Dr. Hans G. Hansson, expert in North Atlantic marine fauna and long-time staff member at Tjärnö marina laboratorium.</p> <p>Description. Animal short and wide, body length 0.45 mm and width to 0.15 mm in squeeze-preparation. Specimens widest at midbody with broadly rounded anterior end and pointed rounded posterior end. Body colorless, transparent, except for parenchyma, which varies from bright green or yellowish-brown based on microalgae food. Digestive parenchyma extends from first ¼ body length to just anterior of posterior vacuoles. Mouth present just anterior to body’s midpoint. Several vacuoles present laterally in posterior half of the body.</p> <p>Frontal organ well-developed. Statocyst present 50 µm from anterior end, 11–12 µm in diameter with 7-8 µm in diameter statolith. Epidermis completely ciliated and ~5 µm wide in longitudinal sections. Cilia ~6–8 µm long. Rhabdoid glands numerous and scattered across the body. Rhabdoids partially subepidermal, 8–10 µm in length in living specimen.</p> <p>Paired ovaries with numerous eggs. Largest egg medial and slightly posterior to midpoint. Seminal bursa and female gonopore absent.</p> <p>Seminal vesicle present ventral to the ovaries and anterior of the largest egg. False seminal vesicle globular, 22–25 µm in width and to 40 µm long (25–40 µm), extending anterio-laterally to testes.</p> <p>Testes located ~⅓ body length from the anterior end. Gonopore large and distinct, present at midbody, surrounded by a large muscular sphincter. Gonopore 25 µm wide and 12–14 µm long. Small, lightly muscular penis present, 9–10 µm long, straight, connecting directly to the gonopore. Penis highly glandular. Two lateral false seminal vesicles connect to a central false seminal vesicle. False seminal vesicles lack walls and are non-muscular, comprising of a mass of sperm or possibly spermatophore. As typical for the genus (Westblad 1946), the central false seminal vesicle is unconnected to the penis, instead remaining posterior to the penis and directly opening into the gonopore (Figure 11D).</p></div> 	http://treatment.plazi.org/id/CF6B87F3E62B8504FF6FFBE0FE48FE40	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E6298505FF6FFDCCFA1EFADA.text	CF6B87F3E6298505FF6FFDCCFA1EFADA.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Baltalimania ax 1959	<div><p>Baltalimania</p> <p>Soon after its establishment, the three species comprising Baltalimania ax 1959 were split into two genera based on the presence or absence of bursal tissue (Dörjes 1968). Archaphanostoma DöRJES 1968 was erected for those species that possessed an indistinct bursa without a muscular wall (i.e. bursal tissue) while the bursa-less Baltalimania kosswigi DöRJES 1968 remained in a monotypic genus. Following a phylogenetic analysis of nucleotide sequences from three genes that resulted in species with and without bursas nesting together in a single clade, Atherton &amp; Jondelius (2021) synonymized Archaphanostoma and Baltalimania such that Baltalimania comprised a set of nine species, four with and five without bursal tissue.</p> <p>With the addition of the four new species presented here, the results from our phylogenetic analyses reinforces the close relationships of species of Baltalimania with and without bursal tissue, and indicates that bursal tissue within Baltalimania was independently lost in at least two separate evolutionary lines (Figure 1). Our results are thus in accordance with the conclusions of previous studies (Jondelius et al. 2011; Atherton &amp; Jondelius 2021) that found bursal tissue is not a good character with which to differentiate genera of Isodiametridae.</p> <p>Of note, B. arcuatum sp. nov. is only the second species of Baltalimania to possess a bursal nozzle, the other being B. marcusi (HooGE =&amp;= RocHa 2006). Unlike B. marcusi, the nozzle of B. arcuatum appears as a single unit instead of of multiple disparate components that in theory function together along a single spermatic duct through which sperm pass on the way to the ovary (Petrov et al. 2006; Hooge &amp; Tyler 2003). As no DNA sequences are currently available for B. marcusi, it is not possible at this time to assess the homology of the nozzles by molecular phylogenetics, but the complete absence of bursal tissue as well as the presence of several different bursal types (e.g. indistinct without walls and unadorned, indistinct with a nozzle of a single unit, or indistinct with a nozzle of multiple disjoint units) within closely related species makes Baltalimania a particularly interesting candidate for future studies on bursal development. Further, as the bursa receives allosperm, there is potential for coevolution between it, the male copulatory organ, and sperm morphology among isodiametrids.</p> <p>Overall, the four new species of Baltalimania fit well with the other species of the genus, which are characterized primarily by the presence of a large, muscular seminal vesicle as well as by a bursa that is either absent or present but indistinct and without discernable walls. They also all have numerous lipid globules and rhabdoid glands in distinct longitudinal rows. The previous and new species of Baltalimania can all be relatively easily distinguished from each other based on a few morphological characters, summarized in Table 2 as well as Table 1 of Kånneby et al. (2014).</p> <p>A key to the genus is presented below. With the inclusion of the four new species, Baltalimania now comprises a total of 13 species.</p> <p>Key to Baltalimania</p> <p>1. Bursal tissue present................................................................................... 2</p> <p>- Bursal tissue absent................................................................................... 8</p> <p>2. Ovary unpaired....................................................................................... 3</p> <p>- Ovaries paired........................................................................................ 6</p> <p>3. Bursa with nozzle..................................................................................... 4</p> <p>- Bursa unadorned...................................................................................... 5</p> <p>4. Bursal nozzle roughly S shaped; penis very short, ~13 µm; antrum masculinum and posterior vacuole absent...................................................................................... B. marcusi (HooGE=&amp;= RocHa =2006)</p> <p>- Bursal nozzle arched; penis 30–40 µm partially extending into an unciliated antrum masculinum; posterior vacuole present..................................................................................... B. arcuatum sp. nov.</p> <p>5. Penis large, 150–300 µm, partially extending into a large, ciliated male antrum........ B. macrospiriferum WESTbLaD=1946</p> <p>- Penis small, ~45 µm, partially extending into a small unciliated antrum masculinum............. B. microcurvum sp. nov.</p> <p>6. Animal ~ 1 mm in body length; penis large, 200 µm or longer.................................................. 7</p> <p>- Animal 0.4–0.6 mm in body length; penis small, 17–20 µm.................................. B. asinariensis sp. nov.</p> <p>7. Antrum masculinum ciliated............................................................. B. agile JENSEN =1878</p> <p>- Antrum masculinum unciliated................................................. B. histobursalium (DöRJES=1968)</p> <p>8. Ovary unpaired....................................................................................... 9</p> <p>- Ovaries paired....................................................................................... 12</p> <p>9. Posterior vacuole present.............................................................................. 10</p> <p>- Posterior vacuole absent............................................................................... 11</p> <p>10. Penis 55–60 µm; anteriolateral vacuoles present.................................... B. occulta (kåNNEbY= bt a¡.=2014)</p> <p>- Penis 30–50 µm; anteriolateral vacuoles absent...................................... B. ylvae (kåNNEbY= bt a¡.=2014)</p> <p>11. Body length ~ 1.7 mm; penis 80–90 µm, partially extending into a ciliated antrum masculinum; gonopore terminal............................................................................... B. sublittoralis (kåNNEbY= bt a¡ K =2014)</p> <p>- Body length 0.4–0.9 mm; penis 25–40 µm, partially extending into an unciliated antrum masculinum; gonopore subterminal......................................................................... B. fontaneti (kåNNEbY= bt a¡ K 2014)</p> <p>12. Body length 1–1.3 mm; frontal organ well-developed; vacuoles present; male organ located ~⅓ body length from the posterior end................................................................................. B. kosswigi ax 1959</p> <p>- Body length 0.85 mm; frontal organ small; vacuoles absent; male organ located close to the posterior end.................................................................................................... B. salinsula sp. nov.</p></div> 	http://treatment.plazi.org/id/CF6B87F3E6298505FF6FFDCCFA1EFADA	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E6288502FF6FFAACFA1EF962.text	CF6B87F3E6288502FF6FFAACFA1EF962.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Praeaphanostoma DoRJES 1968	<div><p>Praeaphanostoma</p> <p>P. diatomovorum sp. nov. joins P. schillingi (HooGE =&amp;=TYLER 2015) as the second Praeaphanostoma without a penis, a morphology that is incongruous with the proposed diagnostic character of Isodiametridae: a tubular isodiametric penis with inner circular muscles fibres and outer non-anastomosing longitudinal fibres (Hooge &amp; Tyler 2005). Hooge &amp; Tyler (2015) originally described P. schillingi as a species of Haplogonaria DöRJES 1968 because of this discrepancy and assumed the molecular data was due to error. Atherton &amp; Jondelius (2021) later reassigned the species to Praeaphanostoma based on results from their phylogenetic analyses as well as the morphological similarities between P. schillingi and P. rubrum DöRJES =1968. With P. diatomovorum sp. nov., our results strengthen the inclusion of P. schilingi in the genus and suggest that an isodiametric penis should not necessarily be a diagnostic feature of the genus or family.</p> <p>Unfortunately, without the definitive presence of a penis, the generic diagnosis of Praeaphanostoma does overlap with the generic diagnosis of Haplogonaria. Since no sequence data is available for any species of Haplogonaria, current phylogenetic analyses cannot clarify the situation. Representation of Haplogonaria in a comprehensive phylogenetic analysis must be prioritized in the future to establish the relationships between species of Haplogonaria and Praeaphanostoma and to help uncover apomorphic characters for the two genera.</p> <p>P. diatomovorum sp. nov. can be easily distinguished from P. schillingi by the smaller body size and by the lack of bright red body pigmentation. Further, P. diatomovorum sp. nov. can be distinguished from the majority of species of Haplogonaria by its general body shape and size as well as the moderate size of the frontal organ. Finally, it differs from H. minima (WESTbLaD 1946) and H. psammalia FaubEL 1974 by the amount of rhabdoid glands (sparse vs numerous), the size of the bursa (~65 µm in length vs 100–150 µm) and the lack of a bursal cap; and from H. arenaria (ax 1959) by its less well-developed testes, the presence of a short vagina and the absence of vacuoles.</p> <p>Praeaphanostoma neglectum sp. nov. possesses many typical features of the genus: a walled seminal bursa without appendages, a muscular seminal vesicle with an embedded penis and a small frontal organ. However, it is distinguished from the other species by the combination of an unpaired ovary, an absence of vacuoles, and a body length less than 1 mm.</p> <p>With the inclusion of the two new species presented here, there are a total of 18 nominal species of Praeaphanostoma described globally. A key to the genus is presented below.</p> <p>Key to Praeaphanostoma</p> <p>1. Ovary unpaired....................................................................................... 2</p> <p>- Ovaries paired....................................................................................... 11</p> <p>2. Vacuoles present...................................................................................... 3</p> <p>- Vacuoles absent...................................................................................... 6</p> <p>3. Large vacuoles restricted to posterior half of animal; posterior tactile bristle present; gonopore common........................................................................................... P. chaetocaudatum DöRJES 1968</p> <p>- Vacuoles numerous along entire body; tactile bristle absent; gonopores separate.................................... 4</p> <p>4. Seminal vesicle located near mid-body; posterior tail long, tapering, heavily vacuolated; male and female gonopores well separated............................................................................ P. brevifrons DöRJES 1968</p> <p>- Seminal vesicle located closer to posterior end; male and female gonopores close together........................... 5</p> <p>5. With numerous gland cells surrounding the distal portion of the seminal vesicle; penis lumen without glandular materials............................................................................. P. vitreum EHLERS =&amp;= DöRJES 1979</p> <p>- Gland cells surrounding the seminal vesicle few or absent; dense nuclei and glandular material present in penis lumen............................................................................. P. wadsworthi HooGE =&amp;=TYLER 2003</p> <p>6. Body without pigmentation............................................................................. 7</p> <p>- Body pigmentation present.............................................................................. 9</p> <p>7. Body long, 3.5 mm; penis curved, ~200 µm long........................................... P. longum DöRJES 1968</p> <p>- Body length less than 1 mm; penis small or absent........................................................... 8</p> <p>8. Rhabdoid glands sparsely present; penis absent........................................... P. diatomovorum sp. nov.</p> <p>- Rhabdoid glands abundant in rows; penis distinct, 12 µm in length.............................. P. neglectum sp. nov.</p> <p>9. Body brown-olive in color............................................... P. thalasophilum EHLERS =&amp;= DöRJES 1979</p> <p>- Body pigmentation red................................................................................ 10</p> <p>10. Rhabdoid glands sparse; genital atrium absent; muscular penis present......................... P. rubrum DöRJES 1968</p> <p>- Rhabdoid glands numerous; genital atrium present; penis absent..................... P. schillingi (HooGE =&amp;=TYLER 2015)</p> <p>11. Gonopores separate.................................................................................. 12</p> <p>- Gonopore common................................................................................... 13</p> <p>12. Seminal bursa with muscular walls; vaginal sphincter well-developed; rhabdoid glands arranged in longitudinal rows.................................................................................... P. parvum RIEGER =&amp;= oTT 1971</p> <p>- Seminal bursa musculature and vaginal sphincter weak; few rhabdoid glands scattered.......... P. sizilianum (RIEDL 1954)</p> <p>13. Vacuoles numerous along entirety of the body.............................................................. 14</p> <p>- Large vacuoles absent or restricted to posterior body half..................................................... 15</p> <p>14. Vagina lined with microvilli and granular gland cells.............................. P. foramivora HooGE =&amp;=TYLER 2008</p> <p>- Vagina without microvilli and granular gland cells............................. P. musculosum EHLERS =&amp;= DöRJES 1979</p> <p>15. Vacuoles absent; vagina without sphincter....................................... P. gusana HooGE =&amp;=EPPINGER 2005</p> <p>- Posterior vacuoles and vaginal sphincter present............................................................ 16</p> <p>16. Pigmented eyespots present......................................................... P. ornatus (kozLoFF 2000)</p> <p>- Eyespots and body pigmentation absent................................................................... 17</p> <p>17. Genital atrium inconspicuous; penis tubular without lobes......................... P. baltalimaniaformis (DöRJES 1968)</p> <p>- Genital atrium large; penis with paired distal, finger-like lobes.......... P. hyalinorhabdoida (kåNNEbY=&amp;= JoNDELIuS =2013)</p> </div>	http://treatment.plazi.org/id/CF6B87F3E6288502FF6FFAACFA1EF962	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
CF6B87F3E62F8503FF6FF934FC2DFB87.text	CF6B87F3E62F8503FF6FF934FC2DFB87.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Pseudoposthia WESTbLaD 1946	<div><p>Pseudoposthia</p> <p>Only a single species of Pseudoposthia, P. macrogonopora, was previously known, and its reproductive system notably also does not follow that which is typical of Isodiametridae. In this case, P. macrogonopora does not possess a muscular seminal vesicle with an invaginated isodiametric penis but rather a false seminal vesicle unconnected to the muscular penis (Westblad 1946). Its reproductive system is additionally unusual for Acoela in that the seminal vesicle is not fully posterior to the ovaries. Sequences of P. macrogonopora are presented here for the first time as well as two additional new species of Pseudoposthia. Results from our phylogenetic analyses find the clade does nest within Isodiametridae with high support (Figure 1).</p> <p>The reproductive systems of both new species are similar to that of P. macrogonopora, both in the anterior position of the male system, the false seminal vesicle unconnected to a penis and the lack of female accessory organs. Additionally, all three species are unpigmented and possess numerous rhabdoid glands scattered across the body. P. hanssoni sp. nov. can be differentiated from P. macrogonopora by its smaller body size, a smaller sized penis that is also straight, and by the large vacuoles that are restricted to the posterior body half only. P. lata sp. nov. can be distinguished from P. macrogonopora and P. hanssoni sp. nov. in its general body shape, the medium size of the frontal organs and by the fact that the muscular penis is absent. Table 3 summarizes the primary morphological differences between the three species.</p> <p>Emended diagnosis. Body without pigmentation. Frontal organ present, often well-developed. Rhabdoid glands numerous, scattered. Mouth ventral, located approximately at the body’s midpoint and slightly anterior to the male gonopore. Ovaries and testes paired. Seminal bursa, vagina and female gonopore absent. Male reproductive system and gonopore present anterior to the posteriormost portion of the ovary. Male gonopore ventral, surrounded by a heavy muscular sphincter. Penis, when present, without ejactulatory duct and unconnected to a seminal vesicle. False seminal vesicle without walls or musculature present, connecting directly to the gonopore posterior to the penis. Numerous gland cells associated with penis and male gonopore.</p></div> 	http://treatment.plazi.org/id/CF6B87F3E62F8503FF6FF934FC2DFB87	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.		MagnoliaPress via Plazi	Atherton, Sarah;Jondelius, Ulf	Atherton, Sarah, Jondelius, Ulf (2022): Diversity in the family Isodiametridae (Acoela): New species bring back old problems. Zootaxa 5169 (5): 401-424, DOI: https://doi.org/10.11646/zootaxa.5169.5.1
