taxonID	type	description	language	source
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: RM 2.1122, type specimen (Supporting Information, Fig. S 1). Original publication: Steen (1934).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: RM 2.1122 was found in an upright tree stump. Te skull is distinguished by elongate, parallel-sided lateral margins and slender tabular horns that protrude posteriorly far beyond the posterior margin of the skull (Steen 1934). Te maxilla shows an undifferentiated dentition, like Archeria (Holmes 1989), but the morphology is conical or peg-like, unlike the chisel-shaped teeth in Archeria (Holmes 1989) or the recurved apices in Proterogyrinus (Panchen 1970, Holmes 1984). Te vertebral centra known from RM 2.1122 are deeply amphicoelous, distinguishing it from Dendrerpeton and other temnospondyls (Steen 1934). Both single- and double-headed ribs are present (Steen 1934). Tere is no evidence of the forelimbs but the scapulocoracoid is preserved, as well as four clavicles (Carroll 1967). Te pelvis present in the same block as RM 2.1122 was considered by Steen (1934) to be of unknown affinity, but Carroll (1967) associated it with Calligenethlon. It is gracile and bears an extremely slender posterior process and a posteriorlyleaning dorsal process.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: RM 2.1193 a (Supporting Information, Fig. S 2), type specimen of Atopotera moneres Steen, 1934, but was later referred to Calligenethlon watsoni (Carroll, 1967). Original publication: Steen (1934).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: Tese skulls were found in upright lycopsid tree trunks at Joggins. RM 2.1193 was originally named ‘ Atopotera moneres ’ by Steen (1934) but was referred to Calligenethlon by Carroll (1967). Both skulls are clearly embolomeres and are not significantly different from the type of Calligenethlon (Carroll 1967). Tis referral added further knowledge of the anatomy of the cheek margin and anterior skull of Calligenethlon. In all instances, the cheek region was disarticulated from the skull table, possibly indicating a loose atachment in life (Carroll 1967).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: RM 12115 (Supporting Information, Fig. S 3). Original publication: Carroll (1967). Consists of: Pterygoid, interclavicle, radius, and scapula.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: Carroll (1967) tentatively included RM 12115 in the referral of ‘ Atopotera moneres ’ to Calligenethlon, suggesting that it may have been associated with the other ‘ Atopotera ’ material because of the similarity of the matrices. With this referral, part of the palate of Calligenethlon became known. Carroll (1967) describes the pterygoid as having a smooth medial margin and a denticulated ventral surface. Tis morphology has been noted in other Calligenethlon specimens, such as NHMUK R 4553 (Carroll 1967). Te interclavicle was questionably associated with the rest of the ‘ Atopotera ’ material but is consistent with other interclavicles referred to Calligenethlon. Te interclavicle preserves a long posterior stem and an ovoid anterior plate, similar to the morphology seen in Gephyrostegus bohemicus Jaekel, 1902 (Carroll, 1967). Te anteriormost margin bears many thin projections, like the teeth of a comb (Carroll 1967). Tis morphology is also seen in Archeria (Romer 1957).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: NM 10050 (Supporting Information, Fig. S 4). Original publication: Carroll (1967).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: NMC 10050 shows dorsally complete and incomplete intercentra, but always fully embolomerous pleurocentra (Carroll 1967). Te femur of NCM 10050 preserves a long shaf and is more gracile than that of Archeria (Romer 1957). Similarly, the tibia is smaller and more lightly built than that of Archeria (Romer 1957) and other embolomeres.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: NMC 10096 (Supporting Information, Fig. S 5). Original publication: Carroll (1967). Consists of: A basioccipital.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: NMC 10096 may be associated with NMC 10050 (Carroll 1967). Tis is the only braincase material known for Calligenethlon, apart from the braincase material present in the specimen described above. Te basioccipital is bullet-shaped, with a wide posterior width that tapers to a blunt point anteriorly. Te bone is incompletely preserved along most margins but there appears to be the base of a wing-like process on the lef lateral margin of the basioccipital, as is seen in Archeria (Clack and Holmes 1988) and Pholiderpeton (Clack 1987 a).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: NMC 10119 (Supporting Information, Fig. S 6). Original publication: Carroll (1967). Consists of: Clavicle and interclavicle.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: Te interclavicle is known from the type specimen, RM 12115, and NMC 10119. Tese specimens show a broad, flat anterior plate with radiating grooves on the ventral surface. Te bone is diamond-shaped and NMC 10119 particularly shows thin, comb-like structures along the anterior margin. Similar structures are described for Archeria, but Calligenethlon displays them more extensively (Carroll 1967). One clavicle is preserved in NMC 10119, but it is incomplete posteriorly. It shows a broad proximal head with radiating pits and grooves (Carroll 1967). Other clavicles are known from NHMUK R 442, showing a narrow stem and distal head (Carroll 1967).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: UMZC T. 49 (Supporting Information, Fig. S 7). Original publication: Carroll (1967) as DMSW B. 224. Consists of: Right humerus.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: Te humerus of Calligenethlon is also known from NHMUK R 4553 but is much more complete in UMZC T. 49. Te overall morphology of the bone is similar to that in Archeria (Romer 1957) in that it is lightly built and more elongated than those described for Pholiderpeton (Clack 1987 a) or Proterogyrinus (Holmes 1984). It preserves an entepicondylar foramen like Archeria (Romer 1957), Proterogyrinus (Holmes 1984), and other embolomeres. Te entepicondylar region is flat and extends further posteriorly than Pholiderpeton (Clack 1987 a), but not as far as Proterogyrinus (Holmes 1984).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: NHMUK PV R 442 (Supporting Information, Fig. S 8). Original publication: Carroll (1967). Consists of: Ulna, radius, and clavicle.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: Carroll (1967) notes again the similarity in the clavicles and ulna to the morphology of Archeria (Romer 1957) based on this specimen. NHMUK PV R 442 also reveals that Calligenethlon possesses a well-developed olecranon process of the ulna, similar to that seen in Pholiderpeton (Clack 1987 a) and Archeria (Holmes 1989), and quite different from that of Proterogyrinus (Holmes 1984). Te shaf of the ulna in NHMUK PV R 442 is broken distally, but it preserves an elongate, parallel-sided shape, similar to that of Archeria (Romer 1957).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: NHMUK R 4553 (Supporting Information, Fig. S 9), type of Dendryazousa, now Calligenethlon watsoni (Carroll 1967). Original publication: Steen (1934). Consists of: Part and counterpart of the type skull, NHMUK R 4553. Includes the skull table and various disarticulated postcranial bones.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: Tis specimen was named the type specimen of Dendryazousa by Steen (1934) but was later referred to Calligenethlon by Carroll (1967). Te pleurocentra are complete rings and intercentra are incomplete dorsally, like the condition seen in CMN 10050. Te ventral surface of the clavicles is wide and shaped similarly to those in RM 2.1122 and other Calligenethlon specimens. Te ilium is preserved in articulation with the ischium and pubis. It displays the beginnings of a slender posterior process, but it is very incomplete. Te morphology of the ischium is consistent with that of the type specimen in that its dorsal margin is slightly concave as it extends posteriorly (Carroll 1967). Tis character is reminiscent of the ischium morphology described for Archeria (Romer 1957).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: NSM 988 GF 70.1 (Supporting Information, Fig. S 10). Original publication: Godfrey et al. (1991). Consists of: A section of articulated trunk vertebrae, neural arches, and ribs.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: Te vertebral section preserved in NSM 998 GF 70.1 shows progressive ossification of the dorsal suture in the intercentra moving posteriorly down the vertebral column, from a ventral crescent to a fully fused, disc-shaped intercentrum (Godfrey et al. 1991). Both dorsally complete and dorsally incomplete intercentra are preserved in specimen NCM 10050, but NSM 998 GF 70.1 is the first conclusive evidence of both morphologies within one individual. Te neural spines are broad and similar in morphology to those of Proterogyrinus (Godfrey et al. 1991). Tis material also provides the first evidence of a larger embolomere at Joggins, which, if indeed are assignable to Calligenethlon, indicates Calligenethlon could obtain larger body sizes than previously thought.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: RM 20.4984 (Supporting Information, Fig. S 11). Original publication: Godfrey et al. (1991). Consists of: A series of articulated posterior presacral vertebrae, along with haemal arches and neural spines. Also preserved are an ilium, femur, and tarsal bones.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: Te morphology of the ilium in RM 20.4984 is markedly similar to that of the ilium in the Calligenethlon type specimen (Godfrey et al. 1991). However, the length of the posterior process in RM 20.4984 is 220 % that of the type specimen, which, like NSM 988 GF 70.1, suggests Calligenethlon could obtain much larger body sizes than was previously thought.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	materials_examined	Specimen number: NSM 994 GF 1.1 (Fig. 1). Original publication: Holmes and Carroll (2010). Consists of: Articulated anterior half of an embolomere skeleton.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C785561FF12395CEBF1F84A.taxon	discussion	Comments: NSM 994 GF 1.1 is one of very few tetrapod specimens found outside a stump at Joggins. In spite of exceptionally good preservation, the few diagnostic characters known for Calligenethlon were not preserved, making an unequivocal identification impossible (Holmes and Carroll 2010). Because only one embolomere is currently known from Joggins, it was considered most plausible that NSM 944 GF 1.1 has some relation to Calligenethlon (Holmes and Carroll 2010).	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C705567FF723920ED22FDFE.taxon	materials_examined	Type and only species: Calligenethlon watsoni. Holotype: R. M. 2.1122. Type horizon and locality: Found in a slab on the beach adjacent to the Joggins Formation, near the town of Joggins, Nova Scotia, Canada. Exact horizon of origin cannot be determined. Referred specimens: RM 2.1193. a, RM 12115, NMC 10096, NHMUK R 442, NHMUK R 4553, NSM 988 GF 70.1, RM 20.4984, and NSM 994 GF 1.1.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C705567FF723920ED22FDFE.taxon	diagnosis	Revised diagnosis: Embolomere characterized by: narrow skull table with parallel lateral margins and lacking lateral lines; large tabular with elongate single horn extending posteriorly well beyond the occiput; tabular horns parallel to each other; surangular with horizontal crest; conical, non-recurved marginal dentition that is not closely packed; interclavicle with strong fimbriation on anterior edge; atlas pleurocentrum completely ossified dorsally but incomplete ventrally; postaxial pleurocentra robust, well-ossified, and always larger than corresponding intercentra; intercentra wedge-shaped in lateral view; intercentra open dorsally but with increasing dorsal closure and eventual full fusion moving posteriorly along vertebral column in larger individuals; humerus ectepicondyle well-developed with sharp distal hook; anocleithrum present; posterior iliac process extremely elongate and gracile; tail dorsoventrally short.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C705567FF723920ED22FDFE.taxon	description	Reconstruction of Calligenethlon watsoni Full-body reconstructions of Calligenethlon watsoni are presented in Figure 25. Tese draw on NSM 994 GF 1.1 and the specimens referred to the genus above. Unpreserved appendicular bones are based on Proterogyrinus. Te first reconstruction (Fig. 25 A) is the most conservative, with a short, Proterogyrinus / Palaeoherpeton - like skull, ‘ standard-length’ neck region, and short trunk. A longirostrine skull reconstruction (Fig. 25 B) was created by moving the maxilla / jugal contact anterodorsally. Two further reconstructions (Fig. 25 C, D) atempt to achieve a more standard presacral count by adding six vertebrae to the posterior end of the NSM 994 GF 1.1 presacral column. In each reconstruction, Calligenethlon emerges as an unusual embolomere with a large head and short, shallow trunk. Te brevirostrine versions especially (Fig. 25 A, C) bear a superficial resemblance to Gephyrostegus (Carroll 1970) in the proportions of the appendicular limbs and morphology of the axial skeleton. Further questions regarding the morphology of Calligenethlon Te confirmation of consistency in the anatomy observed among specimens of Calligenethlon leads to the question of the great disparity in sizes from the smallest specimen, NHMUK R 4553, to the largest, RM 20.4984. Te former pertains to ‘ Dendryozousa ’, now known as a junior synonym of Calligenethlon (Holmes and Carroll 2010), and shows more poorly ossified centra and a large perforation for the notochord, both of which are considered juvenile characteristics (Holmes 1984). Te other Calligenethlon specimens vary slightly in size, most pertaining to individuals about half the size of Proterogyrinus, but two represent a larger, more Proterogyrinus - sized individual (Godfrey et al. 1991). Such a dramatic difference in size makes a simple explanation of individual variation unlikely, although Godfrey et al. (1991) point out that the differing body sizes may be growth stages of Calligenethlon watsoni. However, most specimens atributed to Calligenethlon show evidence of some maturity, such as tight suturing of the cranial bones, well-developed processes of limb bones, and overall advanced ossification (Carroll 1967, Godfrey et al. 1991, Holmes and Carroll 2010). It is especially telling that the braincase of NSM 994 GF 1.1 is well-ossified. Tese features all indicate that Calligenethlon must have atained some level of maturity while still at a small size (Godfrey et al. 1991, Holmes and Carroll 2010) but much larger sizes were possible. Te common, small specimens might represent individuals near the onset of sexual maturity, and the rare, large specimens might represent older individuals that survived that period of elevated mortality. Morphological and skeletochronological evidence supports this interpretation of Whatcheeria specimens from Delta (Otoo et al. 2021, Whitney et al. 2022). Alternatively, RM 20.4984 and NSM 988 GF 70.1 could represent a second, larger Calligenethlon species than C. watsoni. Embolomere diversity at Joggins	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
214587CD5C705567FF723920ED22FDFE.taxon	discussion	Te potential presence of a large species of Calligenethlon calls for the re-examination of several other large-bodied tetrapod remains from Joggins. An incomplete lower jaw was named ‘ Baphetes ’ minor by Dawson (1870) and figured by Romer (1963). Te classification of this specimen as a baphetid has been challenged and there has been some speculation as to whether this animal should instead be considered an embolomere (Romer 1963, Holmes and Carroll 2010). Te strongly convex curvature of the jaw margin is reminiscent of Archeria, but the dentition is more similar to that of NSM 994 GF 1.1. Te jaw, about 15 cm in length, could belong to a large individual of Calligenethlon watsoni or a new, large-bodied Calligenethlon species. More material is required for a definitive taxonomic conclusion. Another specimen, FGM 998 GF 7.1, is a large pelvis atributed to the Hebert beds’ horizon of the Joggins Formation (Hebert and Calder 2004). Tis pelvis was tentatively assigned to a baphetid, but has recently been re-assigned to an embolomere (Adams et al. in press). Te pelvis preserved in FGM 998 GF 7.1 is distinct in morphology from all other known embolomeres, including Calligenethlon, suggesting the presence of yet another large-bodied embolomere at the locality. Several other specimens, such as FGM 000 GF 15 –– a block preserving scatered cranial and postcranial bones, including possible skull material, ribs, neural spines, and vertebrae –– may add even more embolomere diversity to the locality. Further investigation is required to determine whether these specimens pertain to the larger Calligenethlon species or morph, a distinct taxon encompassing the ‘ Baphetes ’ minor material, or represent a new large embolomere at Joggins. Te presentation of the new Calligenethlon anatomical data here provides a more complete knowledge of embolomere morphology and will aid both the revision of existing embolomere material and the identification of new embolomere material from Joggins.	en	Adams, Gabrielle R., Otoo, Benjamin K. A., Bohus, Caleb P. W., Micucci, Logan M., Maddin, Hillary C. (2025): Anatomy and revised diagnosis of the embolomere Calligenethlon watsoni from Joggins, Nova Scotia, based on micro-computed tomography. Zoological Journal of the Linnean Society (Statistics in Society) 203 (2): 109, DOI: 10.1093/zoolinnean/zlae178, URL: https://doi.org/10.1093/zoolinnean/zlae178
