taxonID	type	description	language	source
1D0087D1C324FFAB3593552D86196964.taxon	diagnosis	Diagnosis: Modified from Fernández-Álvarez et al. (2022). Medium to large adult-sized Enoploteuthoidea with photophores embedded in the muscles of the tentacles; photophores of the surface of the mantle with two different sizes and geometrical assemblages; without visceral or ocular photophores; head and tail with fleshy, gelatinous tissue; nuchal folds present; buccal crown with 8 supports; with hooks, suckers or hard structures on all arms; tentacular clubs with hooks in two series on manus, suckers absent from manus, dactylus reduced, with a terminal pad; very large rhomboidal fins; posterior end of mantle elongate, with a short tail; digestive gland located far posterior to the nuchal cartilage; nidamental glands present; oviducts equally developed.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C324FFA136F65525839B6D54.taxon	description	(Figs 3 – 4; Tables 6 – 7) Diagnosis: Ancistrocheirus with 22 photophores with the pattern 6 + 2 + 4 + 2 + 4 + 2 + 2 in ventral mantle; gladius leaf-shaped with a poorly developed rachis; arm hooks with angles between 61 and 77 º. Synonyms: Loligo alessandrinii Vérany, 1847. Holotype: MHNNice 2007.0.6005, Muséum d’Histoire Naturelle de Nice, France. Type locality: Messina, Sicily, Italy.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C324FFA136F65525839B6D54.taxon	description	Neotype locality: Roses, north-western Mediterranean Sea. Additional material: ICMC 00114. 1 ♂, 52 mm DML, 27 / 09 / 2017, Palamós, 42.1080 ºN, 3.5589 ºE. GenBank COI accession number: OQ 755031. GenBank 12 S accession number: OQ 750426. ICMC 000303, 1 ♀, 181 mm DML, 24 / 04 / 2015, Tarragona, depth 435 – 591 m. ICMC 000403. 1 ♀, 200 mm DML, 06 / 07 / 2023. Arenys de Mar. 41.3679 ºN, 2.7869 ºE, depth 532 m. ICMC 000404. 1 ♀, 160 mm DML, 06 / 07 / 2023, Arenys de Mar. 41.3679 ºN, 2.7869 ºE, depth 532 m. ICMC 000405. 1 ♀, 170 mm DML, 04 / 10 / 2021, Tarragona, 40.8333 ºN, 1.3166 ºE, depth 507 m. ICMC 000406. 1 ♀, 175 mm DML, 31 / 08 / 2021, Tarragona, 40.83333 ºN, 1.4166 ºE, depth 546 m. ICMC 000407. 1 ♀, 210 mm DML, 31 / 08 / 2021, Tarragona, 40.83333 ºN, 1.4166 ºE, depth 546 m. Description Specimens (Fig. 3 A – D) up to 210 mm DML, probably there is sexual dimorphism in size, with the only known mature male being 52 mm DML. Females have gelatinous bodies with a short tail and are purple in colour. The mantle is relatively narrow with an MWI of 35.3 % – 57.9 % of DML. The mantle has 22 photophores with the pattern: 6 + 2 + 4 + 2 + 4 + 2 + 2 (Fig. 3 D). The length of the large rhomboidal fins is 75.2 % – 82.4 % of DML and the FWI is 90.0 % – 115.8 % of DML. The head is large with an HLI of 39.0 % – 50.0 % of DML and a HWI of 26.5 % – 41.9 % of DML. Five large photophores surround each eye, two of them in the ventral surface of the head, two in the dorsal and one in the lateral (Fig. 3 B, D). Two smaller photophores are located between the two ventral photophores close to each eye (Fig. 3 D). The funnel length is 10.3 % – 22.7 % of DML. The funnel component of the locking apparatus is 10.0 % – 12.0 % of DML, the mantle component is 5.6 % – 10.3 % of DML. The mantle component is shallow, extending towards the anterior end of the mantle. The gladius is leaf-shaped with a minute rostrum and a poorly developed rachis (Fig. 3 E). Due to the lack of development in the rachis, it is difficult to identify where the rachis begins, an estimate of 11.4 % – 15.6 % of DML was made. Gladius length ranges between 100.0 % and 123.1 % of DML, variation is probably due to different degrees of mantle contraction due to fixation. The gladius width ranged between 16.7 % and 24.1 % of DML. The dorsal keel depth ranges between 0.6 % and 2.0 % DML. The rostrum ranges between 0.8 % and 2.0 % of DML. The arms are long and approximately equal in length, ranging between 46.5 % and 92.1 % of DML. Each arm has hooks in two indistinct alternating rows. The hooks in Arm IV are approximately 25 % smaller than in the other arms. Approximately 50 hooks on each arm, of which the largest in adults is 4 – 5 mm long, although there is almost no difference in size between the first ~ 15 anterior hooks. The hooks curve between 44 º and 77 º (Fig. 3 F, G). The tips of the arms have approximately 40 small circular suckers in two aligned rows, whose morphology suggests they are transitioning to hooks. The terminal sucker surfaces are covered with ~ 25 small teeth of 10 µm length. The tentacles are long, with a total length of 330 – 544 mm and a TeLI of 194.1 % – 259.0 % of DML and a CLI of 26.0 % – 31.3 % of DML. The club is formed by four or five carpal suckers and knobs, the manus has nine dorsal hooks and eight ventral hooks (Fig. 4; Table 7), the dactylus has 20 – 26 suckers. Hook D 2 is the largest in the dorsal series. Hooks D 1 and D 2 are equal in size to their ventral counterparts. Hook V 4 and V 5 are the largest in the ventral series and in the whole tentacle, being 16.1 % of the club length. The distal dorsal hook D 9 is small and flat; therefore, it could be confused with a sucker of the dactylus. The curvature of the hooks decreased with size, V 8 had the sharpest angle of 37 º while hook D 5 had the largest angle of 58.6 º. The LRL ranges between 5 and 7 mm, averaging at 2.1 % DML. The lower beak length is 242.4 % – 362.3 % of LRL, and the depth is 253 % – 320 % of LRL. The rostrum and shoulders are pigmented, whereas the hood and lateral wings have moderate to no pigment (Fig. 3 H, I). The hood ranges between 60.6 % and 100 % of LRL. The upper beak is more pigmented than the lower beak (Fig. 3 J). The radula (Fig. 3 K) has seven transverse rows of teeth. The R teeth are tricuspid with hooked lateral cusps and an average rachidian length (RL) of 0.47 mm ventrally and 0.56 mm dorsally. The L 1 row is bicuspid with a hooked lateral cup and an overall length of 57.4 % – 126.8 % of RL ventrally and 76.2 % – 111.6 % of RL dorsally, while the L 2 row is unicuspid with a length of 68.1 % – 192.2 % of RL ventrally and 80.4 % – 160.4 % of RL dorsally. The M rows are unicuspid with a length of 85.4 % – 297.1 % of RL ventrally and 124.8 % – 288.6 % of RL dorsally. The male individual ICMC 000114 (52 mm DML) is gelatinous and has a light pink colour. The mantle is relatively narrow with an MWI of 38.8 % of DML. The ventral mantle skin was broken in the posterior end, the photophore pattern in the anterior mantle starts with 6 + 2 + 4, which is also found in the females. The large rhomboidal fins have a 77.1 % FLI. The fins are broad but broken. The head is large with an HLI of 52.2 % of DML and an HWI of 77.1 % of DML. Same head photophore pattern as in females. The funnel length is large: 31.7 % of DML. The funnel component of the locking apparatus is 19.7 % of DML. Arms I and II are the shortest, 79.4 % of DML and 64.9 % of DML, respectively. Each arm has hooks in two indistinct alternating rows. Approximately 50 hooks on each arm, of which the largest are ~ 2 mm, although there is almost no difference in size between the first ~ 15 anterior hooks. The gladius was found to be 50 % longer than the mantle, which is probably due to the contraction of the animal when fixed. The gladius has the same leaf shape as found in mature females. The GWI was 24.3 % of DML, and the dorsal keel depth was 2.3 % of DML. The spermatophoric reaction was triggered and, therefore, the spermatophore (Fig. 3 L) internal structure was not possible to be studied. The specimen had three large spermatophores with an average total spermatophoric length of 27.8 mm, which equals 53.5 % ± 1.8 % of DML. Distribution: Mediterranean Sea and Eastern and Western North Atlantic. Name of the species in phylogenetic studies: ‘ Undescribed Ancistrocheiridaespecies’, ‘ newspeciesofAncistrocheiridae’, and Ancistrocheirus alessandrinii (Roura et al., 2019); Ancistrocheirus sp. (Fernández-Álvarez et al. 2022); Ancistrocheirus sp. 1 (Fernández-Álvarez et al. 2023; this work). Remarks The GenBank sequence OR 304287 comes from a specimen sampled in Indian waters, and it is named here as Ancistrocheirus cf. lesueurii (= Ancistrocheirus sp. 4, Remarks’ section of Ancistrocheirus lesueurii). The molecularly detected Ancistrocheirus sp. 3 and Ancistrocheirus sp. 6 (private sequences available at BOLDSYSTEMS and not added here in the analyses; Supporting Information, Fig. S 1) were collected in Pacific waters. As none of these three species is formally linked to A. lesueurii, it is not possible to exclude based only on molecular characters, if the A. alessandrinii individuals examined here actually belong to A. lesueurii. However, the characteristic morphology of the gladius of A. alessandrinii (Fig. 3 E) diverged from that depicted by Férussac and d’Orbigny (1834 – 48: pl. 11, fig. 2) in the original description of A. lesueurii, as the latter has a very distinctive and well-developed rachis. Thus, there is an objective morphological character supporting the taxonomic treatment suggested in this work. Besides, no individual sequenced in Indopacific waters clusters with individuals of A. alessandrinii as redescribed in this work. The tentacle club (Fig. 4) has 17 hooks with nine dorsal hooks only found in three out of seven female adults. In most other specimens a scar could be found where a ninth hook was expected. That might explain why it has previously been described that Ancistrocheiridae have 15 or 16 hooks (Jereb and Roper 2010). However, some oegopsid squid can have variable numbers of manus hooks [e. g. Onykia knipovitchi (Filippova, 1972) (Jereb and Roper, 2010)]. Additionally, it was found for ICMC 000405 and ICMC 000406 that in the radular teeth, L 1 hooks were tricuspid in some teeth and bicuspid in others, indicating some intraspecific variation in this other character. The spermatophores (Fig. 3 L) are large, with an SpL representing 52.3 % – 55.7 % of DML, and the SpC was three in the studied specimen. Previous measurements by Hoving and Lipinski (2014) of fixed specimens originating from South Africa found relatively smaller spermatophores with SpL 22 % – 46 % DML and a SpC of up to 77. Moreover, some males described by Hoving and Lipinsky (2014) showed developed nidamental glands. South African male Ancistrocheirus were also sensibly larger, up to 265 mm DML for non-intersex males and 320 mm DML for males with nidamental glands (Hoving et al. 2006), while the male specimen of A. alessandrinii was 52 mm DML. The spermatophore morphology of South African Ancistrocheirus is quite different from what was observed in A. alessandrinii, and such morphological differences in reproductive organs indicate speciation (De Queiroz 2007). This species corresponds with Ancistrocheirus sp. 1 from the molecular analyses from this work. So far, this species has been found between Cape Verde to the north-western and eastern Atlantic and the Mediterranean (Fig. 8), a pattern commonly found in many oegopsid squids, probably caused by the barriers created by the ocean currents (Fernández-Álvarez et al. 2023). Roura et al. (2019) unclearly referred to some sequenced specimens from Morocco either as ‘ undescribed Ancistrocheiridae species’, ‘ new species of Ancistrocheiridae’, or A. alessandrinii, and argued that their sequencing might refer to the last taxonomic name, as North Atlantic waters are close to the Mediterranean Sea, where A. alessandrinii was described. Since the type locality of Ancistrocheirus alessandrinii is in the Mediterranean, this name should be applied to Ancistrocheirus sp. 1. All the previous reports of A. lesueurii from Mediterranean waters (e. g. Bello et al. 1994, Zaragoza et al. 2015), including those from the Adriatic (Bello 1991) and Ionian Sea (d’Onghia et al. 1997), are considered here as A. alessandrinii. The holotype MHNNice 2007.0.6005 of Ancistrocheirus alessandrinii is located at Muséum d’Histoire Naturelle de Nice. It was originally described by Vérany (1847) under the name Loligo alessandrinii. This individual was a paralarva; given that the morphology of paralarvae in the family Ancistrocheiridae is currently not well known at the global scale, this description currently does not provide much information towards assigning it to a species. This specimen has deteriorated to dust and has no characters left to study at all. There is no way to recover either molecular or morphological information from the destroyed holotype. Thus, it is considered that the provisions needed to designate a neotype under Articles 75.1 and 75.3.4 of the International Code of Zoological Nomenclature (ICZN and International Commission on Zoological Nomenclature 1999) are met. According to the ICZN Article 76.3, the type locality of the species becomes the locality of the neotype, in this case Roses in the north-western Mediterranean Sea. As both type localities are from the Mediterranean Sea, the ICZN Article 75.3.6 is also satisfied. The proposed neotype ICMC 000316 is conserved in excellent condition, and mitochondrial genes COI and 12 S are sequenced and available at GenBank under the accession numbers OQ 755038 and OQ 750435, respectively. The selection as the neotype of this specimen, which links morphological and molecular data, ensures future taxonomic stability of the name A. alessandrinii. In the juvenile A. alessandrinii specimen sequenced under the GenBank Accession number MW 255567 [complete mitogenome, Fernández-Álvarez et al. (2022)], the gladius had a defined rachis, which is inconsistent with the remaining sequenced specimens, including the relatively small male ICMC 000114 (52 mm DML), which might indicate that the loss of a distinct rachis might be an ontogenetic process, and the distinct gladius shape associated with A. alessandrinii develops after the juvenile stage. Thus, this character might not be suitable for early ontogenetic stages. However, the juvenile with the developed rachis came from the Atlantic, not from the Mediterranean. According to the mGMYC analysis, Atlantic and Mediterranean A. alessandrinii might be two distinct species, and a mild genetic isolation was found among Mediterranean and Atlantic A. alessandrinii specimens, which is unlikely to represent a speciation event. However, it is noteworthy that extremely low distances have been found among described cephalopod species for some mitochondrial markers (e. g. Fernández-Álvarez et al. 2021, Sanchez et al. 2021). Currently, there are no adults molecularly confirmed to be Ancistrocheirus alessandrinii from the Atlantic to ensure if this feature is ontogenetic or an exclusive feature of Mediterranean specimens. Incertae sedis	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C324FFAB3479573D86AA69B7.taxon	diagnosis	Diagnosis: Same as family. Type species: Ancistrocheirus lesueurii d’Orbigny, 1842 in Férussac and d’Orbigny (1834 – 48).	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C332FFBE35A6529083A56FAE.taxon	materials_examined	Examined material NHM 20240066, 1 sex unknown, 33 mm DML, 03 / 06 / 1930, South Africa, 33 º 50 ′ 30 ′′ S, 15 º 46 ′ 00 ′′ E, depth <1200 m. NHM 20240067, 1 sex unknown, 54 mm DML, 08 / 11 / 1966, Canary Islands, 28 º 5 ′ 12 ′′ N, 14 º 7 ′ 24 ′′ W, depth <100 m. NHM 20240068, 5 sex unknown, 33 mm DML, 27 mm DML, 23 mm DML, 21 mm DML, 20 mm DML, 20 / 09 / 1961; Canary Islands; 32 º 31 ′ 0 ′′ N, 16 º 49 ′ 30 ′′ W; depth <170 m. NHM 20240069, 3 sex unknown, 40 mm DML, 27 mm DML, 21 mm DML, 25 / 10 / 1966, Canary Islands, 32 º 55 ′ 1 ′′ N, 16 º 48 ′ 6 ′′ W, depth unknown. NHM 20240070, 1 sex unknown, 45 mm DML, 31 / 10 / 1969, North Atlantic, 21 º 29 ′ 52 ′′ N, 25 º 31 ′ W, depth <200 m. NHM 20240071, 1 sex unknown, 22 mm DML, 01 / 08 / 1987, North Atlantic, 40 º 1 ′ 36 ′′ N, 21 º 11 ′ W, depth 885 – 775 m. NHM 20240072, 1 sex unknown, 12.7 mm DML, 26 / 07 / 1974, South Atlantic, 0 º 20 ′ S, 22 º 30 ′ W, depth 28 – 10 m. NHM 20240073, 1 sex unknown, 18 mm DML, 29 / 10 / 1966, Madeira Islands, 32 º 32 ′ 0 ′′ N, 16 º 53 ′ 0 ′′ W, depth unknown. NHM 20240074, 1 sex unknown, 20 mm DML, date unknown, location unknown, depth <300 m. NHM 20240075, 1 sex unknown, 19 mm DML, 26 / 05 / 1964, Oman, 17 º 6 ′ 54 ′′ N, 55 º 27 ′ 0 ′′ E, depth <100 m. NHM 20240076, 1 sex unknown, 18 mm DML, date unknown, location unknown, depth unknown. NHM 20240078, 1 sex unknown, 25 DML, 07 / 06 / 1962, Venezuela, 11 º 24 ′ 30 ′′ N, 67 º 8 ′ 0 ′′ W, depth <400 m. NHM 20240080, 1 ♀, 225 mm DML, 1960 – 1969, South Africa, 33 º 4 ′ S, 18 º 0 ′ E, depth unknown. NHM 20240081, 1 ♀, 165 mm DML, date unknown, South Africa, 29 º 51 ′ S, 31 º 0 ′ E, depth unknown. NHM 20240084, 1 ♀, 130 mm DML, date unknown, South Africa, 33 º 4 ′ S, 18 º 0 ′ E, depth unknown. 254 Tasmin, 1 sex unknown, DML unknown, date unknown, Tasman Sea, 40 ºS, 155 ºE, depth unknown. ZMA. MOLL. 2514234, 3 specimens, 2 sexes unknown, DML unknown; 45 mm DML, 1 ♂ 60 mm DML, 14 / 06 / 1979, North East Atlantic Ocean, 33 º 43 ′ N, 15 º 30 ′ W, depth 200 m. ZMA. MOLL. 2514233, 2 specimens, 1 sex unknown, 68 mm DML, 1 ♂ 63 mm DML, 13 / 06 / 1979, North East Atlantic Ocean, 37 º 23 ′ N, 11 º 04 ′ W, depth 200 m. RMNH. MOL. 518384, 1 sex unknown, 44 mm DML, 04 / 08 / 1992, Gulf of Aden, 12 º 9 ′ N, 47 º 15 ′ E, depth unknown. RMNH. MOL. 518385, 1 sex unknown, 19 mm DML, 04 / 08 / 1992, Gulf of Aden, 12 º 9 ′ N, 47 º 15 ′ E, depth unknown. RMNH. MOL. 518386, 2 sex unknown, 12 mm DML, 15 mm DML, 28 / 08 / 1992, Indian Ocean, 7 ºN, 53 ºE, depth unknown. RMNH. MOL. 518387, 1 sex unknown, 18 mm DML, 02 / 02 / 1993, Red Sea, 14 º 34 ′ 48 ′′ N, 42 º 19 ′ 47 ′′ E, depth unknown. RMNH. MOL. 518389, 1 sex unknown, 19 mm DML, 04 / 02 / 1993, Red Sea 16 º 0 ′ N, 41 º 33 ′ 36 ′′ E, depth unknown. ZMA. MOLL. 434784, 1 sex unknown, DML unknown, date unknown, South Georgia Island, 54 º 8 ′ 60 ′′ S, 36 º 27 ′ 0 ′′ E, depth unknown. ICM 102 / 2002, 1 ♂, 67.2 mm DML, 26 / 04 / 1989, SE Atlantic, 28 º 10 ′ S, 14 º 33 E, 406 m depth. Distribution: Specimens from the North Atlantic, Caribbean, South Africa, the Red Sea, and the Tasmanian Sea. Remarks Although careful morphological examinations were performed, it was not possible to group these specimens into morphospecies. Direct comparisons were challenging, as there were several ontogenetic stages and different degrees of conservation, ranging from entire specimens with well-preserved morphologies to fragments of heavily digested individuals. Variations in characteristics like rigidity, texture, and colour are possibly due to the action of digestive enzymes in individuals collected from the stomachs of whales (specimens NHM 20240066, NHM 20240080, NHM 202400081, NHM 20240084, and Tasmin 254). However, some morphological characters were variable, and this information might be useful in future studies trying to solve other Ancistrocheirus cryptic species. A summary of the variation of the studied morphological characters is available in the Supporting Information, Table S 2, while the raw data of the measures is available in the Supporting Information, Table S 3. These tables and the following paragraphs should not be interpreted as the description of a single species but as the description of the variation found among the studied individuals, which probably represent several species. Spermatophore morphology from ZMA. MOLL. 2514234 (DML 60 mm, north-east Atlantic) was found to be similar to previous descriptions from Hoving et al. (2006) based on much larger specimens collected in South Africa. For ZMA. MOLL. 2514234, the SpC was 1, while Hoving et al. (2006) found an SpC of 2 – 77. The SpLI of the specimen studied here was 41.4 % of DML, within the range Hoving and Lipinski (2014) found of 22 % – 46 %. As Hoving and Lipinski (2014) calculated the spermatophore measurements as a percentage of SpL, the values from this research were translated here to match their indexes. The CBLI of 18.5 % SpL of ZMA. MOLL. 2514234 is slightly larger than the South African Ancistrocheirus sp. from Hoving et al. (2006), which was 7 % – 14 % SpL. The EALI of 30.4 % SpL of ZMA. MOLL. 2514234 falls within the described range of 21 % – 38 % SpL from Hoving et al. (2006). Currently, all molecular data collected from South African specimens have been found to all belong to the same species, Ancistrocheirus sp. 5. Four specimens from South Africa have been morphologically examined (NHM 20240080; NHM 20240081; NHM 20240084; NHM 20240066), and all were collected from the stomach of sperm whales and were partially digested. Morphological differences can be observed in the lower beak of NHM 20240080 compared to specimens from other locations. The specimen has a small rostrum compared to all other beak features, e. g. the lower beak length is 408 % LRL, in comparison to a beak length of 242.4 % – 362.3 % LRL in A. alessandrinii and 260 % LRL in Ancistrocheirus sp. A. The tentacle clubs of NHM 20240066 and NHM 20240084 are large, representing 48.5 % – 53.8 % of DML (N = 2), especially when compared to A. alessandrinii (N = 4) with a CLI of 26.0 % – 31.3 % of DML, and to Ancistrocheirus sp. A (N = 2) with a CLI of 23.9 % – 26.7 % of DML. Arm hook morphology among these South African specimens was often malformed with twisted hooks. All adult miscellaneous specimens from which hooks were extracted were collected from the stomach of sperm whales, so the digestive acids might have altered the arm hook shape. Hoving and Lipinski (2014) described the largest Ancistrocheirus female ever reported with 540 mm of DML, while the largest specimen in this study has a DML of 265 mm. The largest specimen examined from outside South Africa had a DML of 210 mm. Hoving et al. (2006) found approximately half of the males to have nidamental glands, and these males were also found to be larger than males lacking nidamental glands (Hoving and Lipinski 2014). Here, none of the examined males were found to have nidamental glands, however the sample size for males was low, and none of the males originated from South Africa. Individual ICMC 102 / 2002 originates from Namibia, near South Africa. This specimen was a maturing male of 67.2 mm DML with no nidamental glands.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C324FFAB359F57EC823C6B7C.taxon	diagnosis	Diagnosis: Ancistrocheirus with a gladius with a developed rachis. Synonym: Enoploteuthis lesueurii d’Orbigny, 1842. Type specimen: MNHN Holotype 2 – 14 – 614, 2 – 14 – 615 (gladius), 2 – 14 – 616 (beaks) [fide Lu et al. (1995)]. Type locality: Indo-Pacific Ocean (‘ le grand Océan’ in original text) fide Bello (1992). Remarks The type specimen is a male (Bello 1992). The taxonomic history of this name is complicated [see Bello (1992), for comprehensive information]. The currently accepted name was provided by d’Orbigny in 1842 (Férussac and d’Orbigny 1834 – 48), while the figures presented for the description show an asymmetric photophore pattern unlike any known for the genus (Férussac and d’Orbigny 1834 – 48: pl. 14; Fig. 4). Althoughthephotophorepattern depicted by Férussac and d’Orbigny is dubious, the gladius is a very accurate representation showing a well-developed rachis (Férussac and d’Orbigny 1834 – 48: pl. 11; Fig. 2), providing a solid morphological character for future redescriptions. According to Bello (1992), the type locality of this species is the Indo-Pacific Ocean (‘ le grand Océan’ in the original text). The GenBank sequence OR 304287 comes from a specimen sampled in Indian waters, and it is not linked to any published work at present. As this sequence came from near the type locality, but it is unknown if the morphology of this specimen is consistent with the original description of A. lesueurii, it is named here as Ancistrocheirus cf. lesueurii (= Ancistrocheirus sp. 4). The molecularly detected Ancistrocheirus sp. 3 and Ancistrocheirus sp. 6 (private sequences available at BOLDSYSTEMS and not added here in the analyses; Supporting Information, Fig. S 1) were collected in Pacific waters. Formally linking the name A. lesueurii to any morphospecies or any Ancistrocheirus species identified with molecular data would require additional studies.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C32EFFA136DB535C83486B1E.taxon	materials_examined	Holotype: NMNH Holotype 38022, United States. Type locality: 39 º 40 ′ N, 71 º 52 ′ W (north-western Atlantic Ocean). Remarks: The description of the species was a succinct page note without illustrations (Verrill 1882), but it was listed as a synonym of A. lesueurii by Young et al. (1998). As the holotype was in good condition (Roper and Sweeney 1978), remote access to the specimen was gained through Michael Vecchione (NMNH). The specimen was an early Ancistrocheirus subadult whose photophore and chromatophore pattern was difficult to assess. Thus, it was not possible to obtain any useful morphological information to directly link the specimen to a specific Ancistrocheirus cryptic species.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C32EFFA136D5558D82626992.taxon	materials_examined	Holotype: ZMH not extant (Guerrero-Kommritz, pers. comm.). Type locality: South Atlantic Ocean. Remarks: The photophore pattern depicted by Pfeffer (1884) is characteristic of the genus Ancistrocheirus. However, the original description does not provide specific information on the morphological characters that are relevant to differentiate members of the family Ancistrocheiridae. One departure from other descriptions is the presence of longer suckers with teeth at the end of the dactylus. According to Jürger Guerrero-Kommritz (pers. comm.), the holotype was probably destroyed during the Second World War bombings in 1943 (Guerrero-Kommritz 2001). It is not possible to directly link any of the Ancistrocheirus cryptic species discovered through molecular methods to this name at present, but the best candidate so far is Ancistrocheirus sp. 5, as the specimens were collected in South Africa.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C32EFFA3317E560A835A68AC.taxon	description	(Figs 5 – 6; Tables 8 – 9) Examined material: NHM 20240083, 2 ♀♀, 165 and 180 mm DML, North Atlantic Ocean, 47 ºN, 6 º 20 ′ W. Description Specimens up to 180 mm DML (Fig. 5 A – D). The body is gelatinous with a short tail and purplish pink in colour. The mantle is relatively narrow with an MWI of 44.4 % – 50.9 % of DML. The mantle has 24 photophores with the pattern 6 + 2 + 4 + 2 + 4 + 2 + 4 (Fig. 5 D). Large rhomboidal fins that extend along almost the whole mantle length 72.2 % – 86.1 % of DML, relatively narrow fins compared to other species in this genus, with a FWI of 84.4 % – 93.9 % of DML. The head is long and narrow with an HLI of 36.1 % – 39.4 % of DML and with an HWI of 27.8 % – 30.3 % of DML. Five large photophores surround each eye, of which two are ventral, two are dorsal, and one is lateral (Fig. 5 D). Two small photophores are located between the two ventral photophores close to each eye (Fig. 5 D). Funnel length is 19.4 % – 21.8 % of DML. The funnel component of the locking apparatus is 10.4 % – 12.0 % of DML, the shallow mantle component is 10.1 % of DML and extends towards the anterior end of the mantle. The gladius is slightly pointed with a developed rachis (Fig. 5 E). The gladius length is 103.0 % – 133.3 % DML. The gladius width is 14.4 % – 16.7 % DML. The rachis in both individuals was broken at the end; however, as only the tips were missing, an estimate of 15.1 % – 18.0 % DML was made. The rostrum was broken for both individuals and could not be measured. Arms are short and relatively equal in length, range 61.7 % – 80 % of DML, with arms II and III slightly longer than I and IV. The average length of Arm I is 116.5 mm, arm II is 125 mm, arm III is 126.5 mm, and arm IV is 113 mm. Each arm has hooks in two indistinct alternating rows. The hooks in Arm IV are approximately one-fourth smaller than in the other arms. Approximately 50 hooks are present on each arm, with the first ~ 15 hooks being similar in size and then decreasing in size towards the tip of the arm. At the tip of the arms there are ~ 30 small suckers. Arm hook curvature is between 33 º and 41 º (Fig. 5 F, G). Tentacles are short, ranging from 148 to 160 mm, representing 82.2 % – 97.0 % of mantle length. The tentacle club is 23.9 – 26.7 % DML. The club is formed by four or five carpal suckers and knobs, the manus has nine dorsal hooks and eight ventral hooks (Fig. 6), the dactylus has 25 – 30 circular suckers. The hook D 3 is largest in the dorsal series, while D 1 and D 9 are smaller than the other dorsal hooks; the remaining dorsal hooks are similar in size. There is a lot of variation in size for all hooks in the ventral series: V 1 is the smallest hook in the ventral series, after which the size steadily increases ~ 2 mm per hook till hook V 4. The hook V 4 is usually slightly smaller than V 5, which is the largest in the ventral series, being 16.2 % of the club length. After hook V 5, the size of the hooks gradually decreases again to hook V 8, which is slightly larger than hook V 1. The curvature of the hooks (Table 9) decrease with size; D 1 had the sharpest angle of 21.5 º, while hook V 5 had the largest angle of 46.8 º. The beak has a greater hood and a lighter pigmentation pattern than in other examined Ancistrocheirus of a similar size (Fig. 5 H – J). The LRL was about 5 mm. The radula has seven transverse rows of teeth. The rachidian teeth are tricuspid with hooked lateral cusps and a rachidian average length of 0.33 mm in the ventral part of the structure and 0.57 mm in the dorsal one. The L 1 row is bicuspid with a hooked lateral cup and an overall length of 67.5 % – 89.7 % RL ventrally and 68.0 % – 80.1 % RL dorsally, while the second lateral row is unicuspid with a length of 108.7 % – 148.1 % RL ventrally and 125.5 % – 140.5 % RL dorsally. The marginal rows are unicuspid with a length of 151.6 % – 233.4 % RL ventrally, the dorsal marginal teeth could not be measured. Locality: North-eastern Atlantic Ocean, 47 ºN, 6 º 20 ′ W. Remarks: The specimens were fixed shortly after capture, as the arms and tentacles show signs of contraction. Thus, they might appear shorter than in others that were fixed long after their death. The early subadult Ancistrocheirus sp. 2 CEP 331, whose complete mitogenome was sequenced under GenBank Accession number OQ 942691 (Fernández-Álvarez et al. 2023), has a photophore pattern and gladius morphology compatible with Ancistrocheirus sp. A. Regrettably, only the mantle of CEP 331 was sampled, and the arm crown cannot be used to determine whether the three specimens are conspecific. Future studies using molecularly identified adult specimens suitable for morphological examination are needed to link Ancistrocheirus sp. A with a molecular species and then to provide an appropriate name for it.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C331FFBE36A951F683DF69E0.taxon	description	Family Mobydickidae fam. nov. Arnold and Fernández-Álvarez Diagnosis: Oegopsida without photophores and with chromatophore pattern reduced to a small area over the ventral and dorsal area surrounding each eye; arms equal in length with 50 + hooks, arms I – III with distinct circular horny rings with one large main cusp and one accessory claw on each side, arm IV with circular horny rings with a thicker area where the main cusp is found in the suckers from other arms; gladius very pronounced and angular, with a long rachis; lower beak broad with a large wing gap; shallow connection between the rachidian teeth and the lateral cusp. Remarks: The morphology of the specimen NHM 20240079 superficially resembles that of Ancistrocheirus as it is a large squid with long fins, tentacles as a subadult or adult, and hooks in the arms. However, it differs from any member of the superfamily Enoploteuthoidea by the absence of any known photophore. The morphology of the horny rings from the central part of arms I – III does not resemble any known from any other known family of oceanic squids. Also, the beak morphology is very different from the very characteristic morphology of Ancistrocheirus spp .. This specimen is also the largest depigmented squid species to the best of our knowledge. We decided to erect the new family for the following reasons: (i) we were not able to find any described family in which this squid could fit; (ii) including it in Ancistrocheiridae would imply radically modifying the diagnosis of the family in one of its most diagnostic characters: the presence of symmetrically arranged photophores; and (iii) we have no guarantee that this specimen is the sister-group of Ancistrocheirus. If it actually is its sister-group, it would not create any taxonomic problem, as the families Ancistrocheuridae and Enoploteuthidae Pfeffer, 1900 are known to be sister-groups (Fernández-Álvarez et al. 2022), and adding another family as a sister of Ancistrocheuridae would not have any further nomenclatural or taxonomic consequence. However, if this squid is added to Ancistrocheiridae, its diagnosis is modified to fit this species in, and later it is discovered that it is not a member of this group, it would create taxonomic instability.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C331FFBE361457A1848368A9.taxon	diagnosis	Diagnosis: Same as family. Etymology: Mobydickia gen. nov. is erected after the fictional albino sperm whale ‘ Moby-Dick’ (Melville 1851), as the squid specimen is depigmented, almost lacking chromatophores, and was collected from the stomach content of a sperm whale hunted by whalers.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
1D0087D1C330FFBF3501519E828168DE.taxon	diagnosis	Diagnosis: Same as genus. Examined material: NHM 20240079. 1 individual of sex unknown collected by Malcolm R. Clarke from the stomach content of a male sperm whale; 175 mm DML; area encompassing the Bellinghausen Sea, the Drake Passage, and the Scotia Sea (Fig. 8, see remarks), 1955 / 1956, Natural History Museum of London (NHM). Type material: NHM specimen 20240079. There is only one specimen available, which was collected from the stomach content of a male sperm whale hunted between 1955 and 1956. Type locality: Antarctic or sub-Antarctic waters, an area encompassing the Bellinghausen Sea, the Drake Passage, and the Scotia Sea. Etymology: The specific epithet ‘ poseidonii ’ is named after the mythological character Poseidon from ancient Greek religions. According to the legends, Poseidon used his trident to create chaotic springs, earthquakes, drownings, and shipwrecks. The hooks of the arms of M. poseidonii, with their main cusps and accessory claws, resemble a trident. Poseidon is a male character, so the male gender genitive suffix was applied. Proposed vernacular names: Poseidon’s squid (English), calamar de Poseidón (Spanish). Description: Specimen of 175 mm DML (Fig. 7 A – D). The body is soft and gelatinous with a short tail and is white in colour. The mantle is relatively narrow with an MWI of 58.9 %. No photophores are present on the skin, around the eyes, or on the examined internal organs of the specimen. Chromatophores are solely found surrounding each eye, on both the dorsal and ventral surfaces. The fins extend to less than half of the length of the mantle, with a FLI of 42.3 % of DML. The head is relatively short and wide with an HLI of 15.4 % of DML and an HWI of 34.3 % of DML. The funnel is large, representing 28.6 % of the DML. The length of the funnel component of the funnel-mantle locking apparatus (Fig. 7 E) is 16.6 % of DML; the mantle component is 10.4 % of DML and shallow, extending towards the anterior end of the mantle. The gladius (Fig. 7 F) is long, representing 136.6 % of DML and relatively narrow, with a GWI of 17.0 % of DML. It has a dorsal keel depth of 1.7 mm. The rostrum and rachis are long, 3.6 mm and 32 mm, respectively. The rachis is very pronounced and angular. The arms are long and similar in length, ranging between 98.3 % and 102.9 % of DML. At least 50 suckers in each arm, placed in two indistinct alternating rows. In the central area of arms I – III, the horny rings are developed into hooks (Fig. 7 G, H), with one larger main cusp and one smaller accessory claw on each side. Proximal and terminal horny rings of arms I – III are circular hard structures with a thicker area where the main cusp is found in the suckers from the midportion of the arms. The proximal suckers start smaller and increase in size until the maximum diameter and length at sucker 4, and then they gradually decrease. The posterior hooks are less pronounced hooks and until they become circular horny rings. Arms IV have only the flat circular hard structures with a thicker area present in the proximal and distal parts of arms I – III and are approximately one-fourth smaller than the suckers from the other arms (Fig. 7 I, J). The LRL is 5.0 mm, which is equal to 3.1 % of DML. The lower beak length is 254 % of LRL, and the depth is 280 % of LRL. The wings are wide, representing 120 % of LRL. The hood is large, representing 110 % of LRL, and the wing gap is 106 % of LRL. The rostrum and shoulders are heavily pigmented, whereas the hood and lateral wings are moderately pigmented (Fig. 7 K, L). The upper beak is only darkly pigmented in the rostrum area (Fig. 7 M). The radula has seven transverse rows of teeth (Fig. 7 N). The rachidian tooth is tricuspid with hooked lateral cusps and a mean rachidian length of 0.45 mm in the ventral part of the radula and 0.63 mm in the dorsal part. The L 1 row is bicuspid with a hooked lateral cusp and an overall length of 82.0 % – 85.0 % of RL ventrally and 81.8 % – 93.5 % of RL dorsally, while the L 2 row is unicuspid with a length of 97.6 % – 107.2 % of RL ventrally and 133.4 % – 152.5 % of RL dorsally. The marginal rows are unicuspid with a length of 88.7 % – 89.3 % of RL ventrally and 158.0 % – 172.0 % of RL dorsally. No gonads were found in this specimen, but it cannot be confirmed whether it represents an immature specimen or the gonads were missed during ingestion, as the mantle was opened and some internal organs were missing. Distribution: Probably Antarctic and sub-Antarctic waters around the Bellinghausen Sea, the Drake Passage, and the Scotia Sea (Fig. 8), further distribution unknown. Remarks: The colour of the specimen is white (Fig. 7 A, C), and distinct chromatophores were only found in the ventral and dorsal head surfaces next to each eye. While it can be argued that this colour could have been the effect of being partially digested or of being preserved for a long period, it is true that (i) the skin was intact almost completely in well-preserved body parts; (ii) some chromatophores were present in the skin near the eyes, which was not distinctly less digested than in the remaining body; and (iii) other specimens collected from sperm whales stomach contents by the same author (Malcolm Clarke, 1913 – 2013), and kept in the same collection (one of which since the 1960 s) and most likely under the same conditions, including some individuals with signals of longer digestion times, showed good preservation of both chromatophores and photophores. Therefore, the pale colour of this specimen and the absence of photophores most likely represent the true condition of the species. The fins and tentacles are broken and, therefore, are not included in the description. The beak pigmentation has probably been altered due to the action of the digestive enzymes and acidic environment of the sperm whale stomach. The arm armature of M. poseidonii distantly resembles those present in octopoteuthid squids, with hooks with a main cusp and accessory claws (Kelly 2019). The accessory claws might provide an enhanced grip. Most of the internal organs of M. poseidonii were missing. Thus, the gut content was not examined. It must be noted that M. poseidonii differs from octopus squids in many characters, such as the presence of tentacles, absence of photophores, and the beak, arm hooks, and gladii morphology.	en	Arnold, Sam, Nos, David, Sáez-Liante, Raquel, Fernández-Álvarez, Fernando Á. (2025): Diversity in the squid family Ancistrocheiridae and description of a new family of the order Oegopsida (Cephalopoda). Zoological Journal of the Linnean Society 204 (3), DOI: 10.1093/zoolinnean/zlaf074, URL: https://doi.org/10.1093/zoolinnean/zlaf074
