Pareledone, ROBSON, 1932

Allcock, A. L., 2005, On the confusion surrounding Pareledone charcoti (Joubin, 1905) (Cephalopoda: Octopodidae): endemic radiation in the Southern Ocean, Zoological Journal of the Linnean Society 143 (1), pp. 75-108 : 77-105

PARELEDONE ROBSON, 1932

Emended diagnosis

Mantle saccular. Stylets present. Arms with uniserial row of suckers. Right third arm of males hectocotylized; copulatory organ with clearly differentiated ligula and calamus, ligula groove shallow and without marked transverse ridges; arm tips not otherwise modified. Suckers moderately large; distinct enlarged suckers absent. Web well developed. Funnel organ VVshaped or W-shaped. Ink sac present or absent; anal flaps present or absent. Radula composed of rachidian, two pairs of unicuspid lateral teeth, a pair of unicuspid marginal teeth and a pair of marginal plates. Beak is of the classic octopodid form with rostral tip of lower beak rounded. Chromatophores absent from connective tissue covering dorsal surface of digestive gland.

Type species

Eledone charcoti Joubin, 1905 . By subsequent diagnosis.

Remarks

Some studies have suggested that stylets are absent in Pareledone (e.g. Lu & Stranks, 1994). They are absent in Adelieledone polymorpha ( Robson, 1932) which was placed, until recently, in Pareledone ( Allcock et al., 2003) , but appear to be present in all other Pareledone species where they are extremely small and delicate. They may therefore easily be overlooked.

Previous descriptions of Pareledone have also suggested that the funnel organ may be VV-shaped or Wshaped, but usually this is because species of the genus Adelieledone Allcock et al., 2003 (which are Wshaped) have been included in the description. During this study, perhaps because of the large number of specimens examined, there appears to be greater variation in the form of the funnel organ than was previously appreciated. It is not known how much of this variation may be attributed to fixation since the funnel organ is usually not visible prior to fixation.

The web depth index for Pareledone species gives the impression that the web is deep. This is not apparent on visual inspection rather than measurement and calculation. This is because of the way octopuses are measured. The arms of Pareledone are relatively short compared to their width, and even if there were no web, the distance from the centre of the oral surface to the edge of the brachial crown would be at least 20% of the arm length. Under the scale proposed at the CIAC 2003 taxonomy workshop this equates to ‘moderate’ depth (a result of 25% or greater equates to ‘deep’) even though the web itself (excluding the brachia) may be extremely shallow.

PARELEDONE CHARCOTI ( JOUBIN, 1905)

( FIGS 1A–G , 9A , 10A , 11A, TABLE 1)

Eledone charcoti Joubin, 1905: 22 , pl. 3, figs 1, 2.

Not Eledone charcoti – Joubin, 1914: 35, figs 1, 2. – Odhner, 1923: 6.

Not Graneledone charcoti – Robson, 1930: 388.

Moschites charcoti – Hoyle, 1912: 279, text-figs 6, 7 Not Moschites charcoti – Massy, 1916: 151, figs 12-21. Not Moschites aurorae Berry, 1917: 20 , pl. 12, fig. 9, pl. 13, figs 10-12, text-figs 14-20.

Pareledone charcoti – Kühl, 1988: 90 [in part]. – Allcock & Piertney, 2002: 129, fig. 2. – Piatkowski, Allcock & Vecchione, 2003.

Not Pareledone charcoti – Lu & Stranks, 1994: 224– 226, figs 2, 9e- h. – Okutani, 1986: 279, pl. 3. – Piatkowski et al., 1998: 43. – Allcock, 1997: 92, pl. 4: 10. – Allcock et al., 2001: 835.

Pareledone cf. charcoti type 2 – Piatkowski et al., 1998: 43.

Pareledone sp. 16 – Allcock, 1997: 125, fig. 4.8, pl. 4.17.

Material examined

Lectotype: MNHN 5.7 .1095, Ile Wandel, 65∞05¢S, on the shore, coll. ‘Charcot’ Antarctic Expedition, 3.ix.1904: 1♀ submature 32 mm ML.

Other material: NMSZ 2002037.044 , RV Polarstern, stn 61/051–1, 31.i.2002, 61∞12¢S, 54∞50¢W, 62–94 m: 1♂ immature [31] mm ML, 8♂ mature 30 [38], 37 [38], 36 [39], 36 [40], 42 [42], 37 [44], 37 [45], 36 [47] mm ML, 1♀ submature 33 [37] mm ML, 1♀ mature 43 [54] mm ML.

Material examined found to be misidentified as P. charcoti

MNHN 5.7 .1094, Admiralty Bay , King George Island, 418 m. BMNH 1919.12 .30.5, 1919.12.30.29–45, Terra Nova Stn 338, McMurdo Sound, 379 m. BMNH 1919.12 .30.18, Terra Nova Stn 194, off Oates Land, 329– 366 m. BMNH 1919.12.30.2–4, Terra Nova Stn 294, Ross Sea, 289 m. BMNH 1919.12 .30.17, Terra Nova Stn 42, off Rio de Janeiro, 73 m. BMNH 1919.12 .30.1, Terra Nova Stn 349, McMurdo Sound, 146 m. BMNH 1951.4.26.5–17, Discovery , various stns, South Georgia . NMV F22851 , ANARE, Mawson Station , ‘shallow water’ . NMV F65691 , ANARE, Fram Bank , 256 m.

Comparative material examined

Moschites aurorae Berry, 1917 , holotype [AM C40891], Mawson Antarctic Expedition stn 8, off Queen Mary Land, 66∞08¢S, 94∞17¢E, 219 m.

Pareledone framensis Lu & Stranks, 1994 , paratype [NMV F65667 ], RV Aurora australis stn AA91-100, off MacRobertson Land, 67∞27.35¢S, 68∞50.34¢E, 145– 150 m.

Pareledone prydzensis Lu & Stranks, 1994 , paratype [NMV F65625 ], RV Aurora australis stn AA91-89 (2), off Amery Iceshelf, 66∞47¢S, 72∞36¢W, 526–532 m.

Eledone turqueti Joubin, 1905 , lectotype [MNHN 5.7.1089], ‘ Charcot ’ Antarctic Expedition, Ile Wandel, 65∞ 05¢S, 25 m.

Moschites harrissoni Berry, 1917 , holotype [AM C40892], Mawson Antarctic Expedition stn 10, off Shackleton Glacier, 65∞06¢S, 96∞13¢E, 494–595 m.

Moschites antarcticus Thiele, 1920 ; lectotype [ ZMB Moll 110001a], Kaiser Wilhelm II Land, 66∞47¢S, 89∞20¢E, 385 m.

Moschites adelieana Berry, 1917 , holotype [AM C40889], Mawson Antarctic Expedition stn 2, off Mertz Glacier, Adelieland, 66∞55¢S, 145∞21¢E, 450–549 m.

Graneledone polymorpha Robson, 1930 , holotype (BMNH 1951.4.26.26], Discovery Expedition stn 42, South Georgia, 120–204 m.

Diagnosis

Papillae are irregularly shaped and flat topped. They stop abruptly at the lateral fold. There is a single supraocular papilla over each eye. There are no other enlarged papillae. The ventral mantle is creamy white. The hectocotylized arm bears 26–28 suckers.

Redescription

Based on specimens detailed in Table 1. Animals small, ML to 43 mm, TL to 118 mm ( Fig. 1A ). Mantle approximately spherical (MWI 98.5 ± 5.1), head narrower than mantle (HWI 71.0 ± 2.2). Web deep (WDI 38.0 ± 4.4), web formula approximately C = D.B.E.A. Funnel medium-sized (FuLI 45.7 ± 3.6), gently tapered; funnel organ W- or V-shaped. Gills with 7–9 lamellae per demibranch. Arms short (MAI 56.1 ± 5.3). Arm lengths subequal, arm order usually 3 = 4.2.1 (ALI L1151.9 ± 8.5; L2169.4 ± 11.3; L3179.0 ± 16.3; L4179.6 ± 16.3). Suckers uniserial, medium-sized (ASI 10.3 ± 1.2), without sucker enlargement. Third right arm of males hectocotylized, usually shorter than opposite number (OAI 90.9 ± 3.9). Ligula moderate to large (LLI 11.4 ± 0.8); ligula groove long, well-marked and shallow, without marked transverse ridges ( Fig. 1B ). Calamus distinct and large to very large (CaLI 50.3 ± 7.1). Hectocotylized arm with 26–28 suckers, opposite arm with up to 42 suckers. Male reproductive system ( Fig. 1F ) with markedly long Needham’s sac storing up to 5 spermatophores. Penis large, penis diverticulum coiled. Spermatophores ( Fig. 1G ) long (SpLI 150.8 ± 7.2) and slender.

Female reproductive system ( Fig. 1H ) consists of ovary containing up to 80 eggs, paired oviducts with large dark oviducal glands. Eggs with approximately 16 follicular folds ( Fig. 1I ). Mature ovarian eggs large (> 10 mm). Digestive system with buccal mass approximately equal in size to posterior salivary glands ( Fig. 1D ). Anterior salivary glands small and closely associated with buccal mass. Short oesophagus leads into crop; crop with diverticulum. Stomach leads into coiled caecum. Anus winds around right hand side of digestive gland. Ink sac present. Anal flaps present. Beak is unremarkable ( Fig. 1E ), with rostral tip of lower beak rounded. Radula with nine elements, rachidian multicuspid ( Fig. 10A ).

Papillae are simple but irregularly shaped with a raised flat top ( Fig. 9A ). They cover the entire dorsal surface but stop abruptly at the lateral fold ( Fig. 1C ). The lateral fold is marked anteriorly (towards the pallial aperture) by a slightly raised ridge, itself sometimes marked by the presence of leucophores. Posteriorly there is no distinct division between the dorsal and ventral mantle surfaces, except the abrupt cessation of the papillae. Chromatophores continue beyond the lateral fold onto the surface of the ventral mantle, but here they are much sparser. The centre of the ventral mantle is a creamy white colour with no evidence of chromatophores. There is an enlarged supraocular papilla. There are no other enlarged papillae on the dorsal mantle surface. A freshly dead specimen usually has a dark pink/pale brown hue. Live specimens ( Fig. 11A ) vary greatly in colour and may flush red when disturbed. There is often a rhomboid of paler marking on the dorsal mantle extending from between the eyes to the posterior mantle. Leucophores may be present on the head region between the eyes.

Type locality

Antarctic Peninsula. Booth-Wandel Island [65∞05¢S, 63∞55¢W]. Shore. Expedition Antarctique Française. 3 September 1904 .

Distribution

Off Graham Land [65∞05¢S, 63∞55¢W] in rock pool ( Joubin, 1905); South Shetland Islands, 60∞50¢-63∞00¢S, 54∞44¢-61∞49¢W, 48–392 m (this study); South Orkney Islands, 60∞43¢S, 44∞38¢W, 16–18 m ( Hoyle, 1912).

Etymology

Named after Dr Charcot, leader of the Expedition Antarctique Française.

Remarks

Many of the putative specimens of Pareledone charcoti examined were revealed to be misidentified. In this study, 75% of specimens were found in waters shallower than 120 m ( Fig. 12 ). Many of the misidentified specimens were from far deeper waters. Others were from outside the established range of the genus, e.g. BMNH 1919.12.30.1 from off Rio de Janeiro, or from Antarctic regions such as South Georgia where P. charcoti is known to be absent (see Yau et al., 2002) e.g. BMNH 1951.4.26.5–17, Robson’s series of P. charcoti which have been re-identified as P. turqueti . The most significant specimen found to be misidentified is MNHN 5.7.1094 referred to in Joubin’s (1914) paper. Although this specimen is in poor condition it clearly has simple round papillae and cannot, under the new diagnosis of P. charcoti , be assigned to this species.

PARELEDONE AEQUIPAPILLAE SP. NOV.

( FIGS 2A–C , 9B , 10B , 11B; TABLE 2)

Eledone charcoti . – Joubin, 1914: 35, figs 1, 2. Pareledone charcoti . – Piatkowski et al., 1998: 43 [in part]. – Allcock, 1997: 92 [in part].

Pareledone sp. 12b. – Piatkowski et al. 2003.

ep

Material examined

Holotype: NMSZ 2003152.002 , RV Polarstern, stn 61/ 048–1, 30.i.2002, 61∞10¢S, 54∞34¢W, 278–343 m: 1♂ mature 52 [64] mm ML.

Paratypes: NMSZ 2002037.002 , RV Polarstern, stn 61/ 048–1, 30.i.2002, 61∞10¢S, 54∞34¢W, 278–343 m: 2♀ submature 38 [48], 45 [55] mm ML, 3♀ mature 48 [61], 56 [74], 63 [78] mm ML, 4♂ mature 41 [48], 42 [48], 46 [48], 47 [58] mm ML. NMSZ 2002037.004 , RV Polarstern, stn 61/052–1, 31.i.2002, 61∞21¢S, 55∞14¢W, 264–270 m: 2♀ immature [28], [35] mm ML, 4♀ submature [34], [44], [45], [49] mm ML, 4♂ immature [32], [34], [40], [41] mm ML.

Other material: MNHN 5.7.1094, Admiralty Bay, King George Island, 418 m

Diagnosis

Papillae are simple, round and tall. They stop abruptly at the lateral fold. There is a single supraocular papilla over each eye. There is a pattern of other enlarged papillae on the dorsal mantle. The ventral mantle is creamy white. The hectocotylized arm bears 33–35 suckers.

Description

Based on specimens detailed in Table 2. Animals small- to medium-sized, ML to 63 mm, TL to 191 mm ( Fig. 2A ). Mantle approximately spherical (MWI 99.4 ± 7.5), head narrower than mantle (HWI 68.4 ± 5.2). Web moderate to deep (WDI 26.0 ± 3.0), web formula approximately C = D.B.A.E. Funnel medium-sized (FuLI 48.2 ± 4.0), gently tapered; funnel organ W- or V-shaped. Gills with 6–8 lamellae per demibranch. Arms short (MAI 51.1 ± 4.2). Arm lengths subequal, arm order usually 3 = 4.1 = 2 (ALI L1185.1 ± 16.5; L2185.9 ± 12.5; L3195.1 ± 16.4; L4198.2 ± 14.0). Suckers uniserial, small to medium (ASI 6.9 ± 0.6), without sucker enlargement. Third right arm of males hectocotylized, shorter than opposite number (OAI 84.3 ± 3.6). Ligula moderate to large (LLI 8.8 ± 1.2); ligula groove long, well-marked and shallow, without transverse ridges ( Fig. 2B ). Calamus distinct and large to very large (CaLI 48.2 ± 10.6). Hectocotylized arm with 33–35 suckers, opposite arm with up to 52 suckers. Penis diverticulum coiled. Spermatophores long to very long (SpLI 193.5 ± 9.0) and slender. Mature ovarian eggs large (> 10 mm). Ink sac present. Anal flaps present. Radula with nine elements, rachidian multicuspid ( Fig. 10B ). Other features of digestive and reproductive systems greatly resemble those of P. charcoti .

Papillae are simple and round ( Fig. 9B ). They are long when compared to other simple round papillae seen on Pareledone species and under the microscope they appear as finger-like projections. They cover the entire dorsal surface but stop abruptly at the lateral fold ( Fig. 2C ). Although barely raised, the lateral fold is marked by a line of leucophores. Chromatophores continue beyond the lateral fold onto the surface of the ventral mantle, but here they are much sparser. The centre of the ventral mantle is a creamy white colour with no evidence of chromatophores. There is an enlarged supraocular papilla and an indistinct pattern of slightly enlarged papillae on the dorsal mantle surface. Leucophores are often found in the head region in a characteristic pattern. An area of more dense chromatophores occurs just below the head region, forming a band of dark colour on the dorsal surface which fades laterally and is not present ventrally. Freshly dead specimens are a grey brown colour. Live specimens ( Fig. 11B ) are a richer brown.

Type locality

South Shetland Islands. 61∞10¢S, 54∞34¢W, 278–343 m. RV Polarstern, ANT XIX/3 , Stn 61/048–1, 30.i.2002 .

Distribution

South Shetland Islands, 60∞49¢-62∞36¢S, 55∞14¢- 61∞50¢W, 110–465 m (this study); King George Island, South Shetland Islands, 418 m ( Joubin, 1914).

Etymology

From the Latin aequus (equal) and papilla; refers to the simple, round and even structure of the papillae.

PARELEDONE ALBIMACULATA SP. NOV.

( FIGS 3A–C , 9C , 10C , 11C; TABLE 3)

Pareledone cf. charcoti type 1. – Piatkowski et al., 1998: 43.

Pareledone sp. 15. – Allcock, 1997: 120, pl. 4: 16. – Piatkowski et al. 2003.

Material examined

Holotype: BMNH 1996192 , RV Polarstern, stn 42/021, 21.xi.1996, 61∞19¢S, 56∞33¢W, 480 m: 1♂ mature 29 mm ML.

Paratypes: BMNH 1996193 , RV Polarstern, stn 42/ 021, 21.xi.1996, 61∞19¢S, 56∞33¢W, 480 m: 1♀ mature 33 mm ML. NMSZ 2002037.007 , RV Polarstern, stn 61/044–1, 29.i.2002, 60∞58¢S, 55∞06¢W, 308–399 m: 2♀ immature [25], [25] mm ML, 1♂ immature [18] mm ML. NMSZ 2002037.008 , RV Polarstern, stn 61/047–1, 30.i.2002, 61∞04¢S, 54∞36¢W, 308–399 m: 2♀ mature 34 [41], 38 [46] mm ML, 1♂ immature 28 [29] mm ML, 1♂ submature 30 [35] mm ML. NMSZ 2002037.009 , RV Polarstern, stn 61/052–1, 31.i.2002, 61∞21¢S, 55∞14¢W, 264–270 m: 1♂ mature 38 [38] mm ML. NMSZ 2002037.010 , RV Polarstern, stn 61/101–1, 13.ii.2002, 61∞49¢S, 58∞35¢W, 321–399 m: 1♂ mature 36 [38] mm ML. NMSZ 2002037.011 , RV Polarstern, stn 61/103–1, 13.ii.2002, 61∞45¢S, 58∞02¢W, 257– 296 m: 1♀ immature 26 [26] mm ML, 2♀ submature 28 [30], 29 [34] mm ML, 1♂ mature, 31 [33] mm ML.

Diagnosis

Papillae are irregularly shaped and resemble turreted rings. They continue briefly beyond the lateral fold. There is a single supraocular papilla over each eye which appears as a white dot when retracted. There are no other enlarged papillae. The ventral mantle is creamy white. The hectocotylized arm bears 29–32 suckers.

Description

Based on specimens detailed in Table 3. Animals small, ML to 38 mm, TL to 133 mm ( Fig. 3A ). Mantle spherical to ovoid ( MWI 93.6 ± 9.5), head narrower than mantle ( HWI 68.4 ± 5.8). Web moderate to deep ( WDI 24.8 ± 2.8), web formula approximately B = C = D.A = E. Funnel medium-sized (FuLI 46.4 ± 4.0), gently tapered; funnel organ W- or Vshaped. Gills with 6–8 lamellae per demibranch. Arms short ( MAI 50.1 ± 3.6). Arm lengths subequal, arm order usually 3.2.1 = 4 ( ALI L1184.4 ± 14.7; L2192.1 ± 10.5; L3197.6 ± 16.6; L4184.8 ± 17.7). Suckers uniserial, small to medium ( ASI 7.2 ± 0.7), without sucker enlargement. Third right arm of males hectocotylized, shorter than opposite number ( OAI 82.4 ± 4.9). Spermatophoric groove particularly wide. Ligula moderate to large ( LLI 10.0 ± 1.1); ligula groove long, well-marked and shallow, without transverse ridges but with faint radiating lines in preserved specimens ( Fig. 3B ). Calamus distinct and large to very large (CaLI 44.6 ± 5.2). Hectocotylized arm with 29–32 suckers, opposite arm with up to 50 suckers. Penis diverticulum coiled. Spermatophores long (SpLI 123.1 ± 6.6) and slender. Mature ovarian eggs large (> 10 mm). Ink sac present. Anal flaps present. Radula with nine elements, rachidian multicuspid ( Fig. 10C ). Other features of digestive and reproductive systems greatly resemble those of P. charcoti .

Papillae are irregularly shaped. They are broad and both raised and slightly ‘turreted’ at the edges ( Fig. 9C ). It is not clear whether they are simple or compound; it is possible that each irregular papilla is constructed from number of small fused papillae arranged in a ring, hence the turreted appearance. They cover the entire dorsal surface and continue over the lateral fold for approximately 1 cm, decreasing in height and width away from the lateral fold ( Fig. 3C ). The lateral fold is marked posteriorly by a small but continuous ridge. Anteriorly (towards the pallial aperture) there is no distinct division between the dorsal and ventral mantle surfaces. Chromatophores continue beyond the lateral fold onto the surface of the ventral mantle, but here they are much sparser. They stop where the papillae cease.

The centre of the ventral mantle is a creamy white colour with no evidence of chromatophores. There is an enlarged supraocular papilla which when contracted appears as a small white spot. When extended it may be up to 5 mm in length. There are no other enlarged papillae on the dorsal mantle surface. A freshly dead specimen usually has a pink hue. Live specimens ( Fig. 11C ) are usually mottled pink and white.

Type locality

South Shetland Islands. 61∞19¢S, 56∞33¢W, 338– 429 m. RV Polarstern, ANT XIV/2 , Stn 42/021, 21.xi.1996 .

Distribution

South Shetland Islands, 60∞50¢– 62∞43¢S, 54∞37¢- 58∞51¢W, 190–465 m (this study).

Etymology

From the Latin alba (white) and macula (spot); refers to the supraocular papilla which, when the animal is resting, resembles a white spot above the eye.

PARELEDONE AURATA SP. NOV.

( FIGS 4A–C , 9D , 10D , 11D; TABLE 4)

Pareledone charcoti – Piatkowski et al., 1998: 43 [in part]. – Allcock, 1997: 92 [in part].

Pareledone sp. 12a. – Piatkowski et al. 2003.

Material examined

Holotype: NMSZ 2003152.001 , RV Polarstern, stn 61/052–1, 31.i.2002, 61∞21¢S, 55∞14¢W, 264–270 m: 1♂ mature 41 [50] mm ML.

Paratypes: NMSZ 2002037.003 , RV Polarstern, stn 61/ 052–1, 31.i.2002, 61∞21¢S, 55∞14¢W, 264–270 m: 1♀ immature 26 [28] mm ML, 3♀ submature 34 [31], 42 [46], 44 [51] mm ML, 1♀ mature 49 [56] mm ML, 2♂ immature [26], 31 [37] mm ML, 3♂ submature 37 [40], 35 [42], 37 [44] mm ML.

Diagnosis

Papillae are simple and round. They mostly stop abruptly at the lateral fold except anteriorly (at the pallial aperture) where a few encroach onto the ventral surface. There is a single supraocular papilla over each eye. There are no other enlarged papillae. The ventral mantle is creamy white. The hectocotylized arm bears 27–29 suckers.

Description

Based on specimens detailed in Table 4. Animals small, ML to 49 mm, TL to 136 mm ( Fig. 4A ). Mantle spherical to ovoid ( MWI 88.6 ± 7.3), head narrower than mantle ( HWI 64.0 ± 5.5). Web deep ( WDI 39.2 ± 2.7), web formula approximately C.B = D.A.E. Funnel medium-sized (FuLI 47.0 ± 3.5), gently tapered; funnel organ W- or V-shaped. Gills with 7–8 lamellae per demibranch. Arms short ( MAI 65.8 ± 5.6). Arm lengths subequal, arm order usually 3 = 4.1 = 2 ( ALI L1139.8 ± 13.6; L2142.7 ± 16.1; L3151.0 ± 14.9; L4149.4 ± 11.6). Suckers uniserial, small to medium ( ASI 7.1 ± 0.9), without sucker enlargement. Third right arm of males hectocotylized, usually shorter than opposite number ( OAI 93.6 ± 4.9). Ligula moderate to large ( LLI 11.3) in only mature male examined; ligula groove long, wellmarked and shallow, without transverse ridges ( Fig. 4B ). Calamus distinct and large (CaLI 42.9). Hectocotylized arm with 27–29 suckers, opposite arm with up to 39 suckers. Penis diverticulum coiled. Spermatophores long (SpLI 134.1) and slender. Mature ovarian eggs large (> 10 mm). Ink sac present. Anal flaps present. Radula with nine elements, rachidian unicuspid ( Fig. 10D ). Other features of digestive and leu reproductive systems greatly resemble those of P. charcoti .

Papillae are simple and round ( Fig. 9D ). They cover the entire dorsal surface but stop abruptly at the lateral fold, except at the anterior extreme (at the pallial aperture) where they extend a few mm on to the ventral surface ( Fig. 4C ). The lateral fold is marked anteriorly (towards the pallial aperture) by a small ridge. Posteriorly there is no distinct division between the dorsal and ventral mantle surfaces except for the abrupt cessation of papillae. Chromatophores continue a few mm beyond the lateral fold onto the surface of the ventral mantle. The centre of the ventral mantle is a creamy white colour with no evidence of chromatophores. There is a small and indistinct (hence easily overlooked) supraocular papilla. There are no other enlarged papillae on the dorsal mantle. Leucophores are present in small irregular patches on the dorsal mantle which sometimes form a V-shape (pointing posteriorly). This patterning does not appear to be consistent. There may also be patches of leucophores on the head and brachial crown. A freshly dead specimen usually has a light blue hue. Live specimens ( Fig. 11D ) are usually pinker.

Type locality

South Shetland Islands. 61∞21¢ S, 55∞14¢ W, 264– 270 m. RV Polarstern, ANT XIX/3 , Stn 61/052–1, 31.i.2002 .

Distribution

South Shetland Islands, 60∞49 – 62∞29¢S, 55∞14¢- 61∞25¢W, 89–465 m (this study).

Etymology

From the Latin aurata (golden), referring to the iridophores that produce distinctive markings on the dorsal mantle and head.

PARELEDONE CORNUTA SP. NOV.

( FIGS 5A–C , 9E , 10E , 11E, TABLE 5)

Pareledone cf. charcoti type 3. – Piatkowski et al., 1998: 43

Pareledone sp. 19. – Piatkowski et al., 2003. – Allcock, 1997: 130, fig. 4.9, pl. 4.18.

Material examined

Holotype: BMNH 1996196 , RV Polarstern, stn 42/004, 16.xi.1996, 61∞10¢ S, 56∞04¢ W, 169–175 m: 1♂ submature 37 mm ML.

Paratypes: BMNH 1996197 , RV Polarstern, stn 42/ 004, 16.xi.1996, 61∞10¢S, 56∞04¢W, 169–175 m: 1♀ submature 39 mm ML. NMSZ 2000081.041 , RV Polarstern, stn 56/177–1, 1.v.2000, 62∞50¢S, 60∞50¢W, 200–202 m: 1♂ immature [29] mm ML, 1♂ submature [34] mm ML. NMSZ 2000081.059 , RV Polarstern, stn 56/183–1, 3.v.2000, 62∞07¢S, 60∞22¢W, 200–204 m: 1specimen (sex undetermined) immature [17] mm ML, 1♂ immature [22] mm ML. NMSZ 2002037.016 , RV Polarstern, stn 61/044–1, 29.i.2002, 60∞58¢S,55∞06¢W, 308–399 m: 1♀ immature [27] mm ML, 1♀ submature [34] mm ML, 1♀ mature 45 [49] mm ML, 1♂ mature 38 [47] mm ML. NMSZ 2002037.017 , RV Polarstern, stn 61/045–1, 29.i.2002, 60∞59¢S, 55∞11¢W, 196–269 m: 2♀ mature 46 [56], 48 [61] mm ML, 2♂ mature [42], 43 [46] mm ML. NMSZ 2002037.018 , RV Polarstern, stn 61/048–1, 30.i.2002, 61∞10¢S, 54∞34¢W, 278–343 m: 3♀ mature 43 [50], 47 [56], 60 [70] mm ML, 2♂ mature 38 [43], 38 [49] mm ML. NMSZ 2002037.019 , RV Polarstern, stn 61/052–1, 31.i.2002, 61∞21¢S, 55∞14¢W, 264–270 m: 1♂ immature [32] mm ML.

Diagnosis

Papillae are large, compound and irregularly shaped. They continue briefly beyond the lateral fold. There are several supraocular papillae. There is a pattern of other enlarged papillae on the dorsal mantle. The ventral mantle is creamy white. The hectocotylized arm bears 29–32 suckers.

Description

Based on specimens detailed in Table 5. Animals small to medium-sized, ML to 60 mm, TL to 162 mm ( Fig. 5A ). Mantle approximately spherical ( MWI 98.1 ± 5.5), head narrower than mantle ( HWI 69.1 ± 5.1). Web deep ( WDI 31.0 ± 2.6), web formula approximately C = D.B = E.A. Funnel medium-sized (FuLI 43.3 ± 4.7), gently tapered; funnel organ W- or V-shaped. Gills with 7–9 lamellae per demibranch. Arms short ( MAI 57.5 ± 3.7). Arm lengths subequal, arm order usually 3 = 4.2.1 ( ALI L1147.6 ± 12.2; L2157.5 ± 12.5; L3168.2 ± 13.1; L4172.6 ± 10.0). Suckers uniserial, small to medium ( ASI 7.3 ± 0.8), without sucker enlargement. Third right arm of males hectocotylized, shorter than opposite number ( OAI 87.6 ± 2.9). Ligula moderate to large ( LLI 9.3 ± 0.8); ligula groove long, well-marked and shallow, with faint transverse ridges ( Fig. 5B ). Calamus distinct and moderate to large (CaLI 34.1 ± 8.7). Hectocotylized arm with 29–32 suckers, opposite arm with up to 49 suckers. Penis diverticulum coiled. Spermatophores long (SpLI 168.9 ± 18.1) and slender. Mature ovarian eggs large (> 10 mm). Ink sac present. Anal flaps present. Radula with nine elements, rachidian multicuspid ( Fig. 10E ). Other features of digestive and reproductive systems greatly resemble those of P. charcoti .

Papillae are very large, compound (with extensive branching) and irregularly shaped ( Fig. 9E ). They cover the entire dorsal surface and continue over the lateral fold for approximately 1 cm, decreasing in height and width away from the lateral fold ( Fig. 5C ). The lateral fold is marked posteriorly where papillae are positioned in a close set line and may be slightly extended, sometimes with leucophores at the extremes. Anteriorly (towards the pallial aperture) there is no distinct division between the dorsal and ventral mantle surfaces, although there may be some leucophores in this region. Chromatophores continue beyond the lateral fold onto the surface of the ventral mantle, but here they are much sparser. They stop where the papillae cease. The centre of the ventral mantle is a creamy white colour with no evidence of chromatophores. There are multiple supraocular papillae, two of which are particularly enlarged. The largest may extend to 10 mm in length. There is a distinctive pattern of enlarged papillae on the dorsal mantle surface and a distinctive pattern of leucophores, although the latter does display a degree of variability. A freshly dead specimen usually has a light brown hue. Live specimens ( Fig. 11E ) are usually darker and redder; they can use their papillae to alter their external appearance.

Type locality

South Shetland Islands. 61∞10¢S, 56∞04¢W. 169–175 m. RV Polarstern, ANT XIV/2 , Stn 42/004, 16.xi.1996 .

Distribution

South Shetland Islands, 60∞49¢-62∞50¢S, 54∞34¢- 60∞49¢W, 130–454 m (this study).

Etymology

From the Latin cornuta (horned), referring to the very large supraocular papillae found in this species.

PARELEDONE PANCHROMA SP. NOV.

( FIGS 6A–C , 9F , 10F , 11F; TABLE 6)

Graneledone sp. – Piatkowski et al., 1998: 43? Graneledone sp. 29. – Allcock, 1997: 85, fig. 4.2.

sp. 29. – Piatkowski et al. 2003.

Material examined

Holotype: NMSZ 2003152.005 , RV Polarstern, stn 56/178–2, 2.v.2000, 61∞59¢S, 60∞19¢W, 804–930 m: 1♂ mature 33 [44] mm ML.

Paratypes: NMSZ 2000081.051 , RV Polarstern, stn 56/ 178–2, 2.v.2000, 61∞59¢S, 60∞19¢W, 804–930 m: 2♀ immature [33], [34] mm ML, 1♀ submature 29 [43] mm ML, 2♀ mature 43 [48], 41 [50] mm ML, 4♂ mature 28 [35], 32 [38], 34 [40], 35 [40] mm ML. NMSZ 2000081.060 , RV Polarstern, stn 56/178–2, 2.v.2000, 61∞59¢S, 60∞19¢W, 804–930 m: 1♀ submature 32 [39] mm ML. NMSZ 2002037.023 , RV Polarstern, stn 61/098–1, 10.ii.2002, 61∞06¢S, 56∞07¢W, 442– 458 m: 2♂ mature [28], [31] mm ML. NMSZ 2002037.024 , RV Polarstern, stn 61/101–1, 13.ii.2002, 61∞49¢S, 58∞35¢W, 321–399 m: 1♂ submature [26] mm ML. NMSZ 2002037.025 , RV Polarstern, stn 61/120–1, 18.ii.2002, 62∞11¢S, 60∞48¢W, 413–472 m: 1♀ mature 36 [39] mm ML.

Diagnosis

Papillae are irregularly shaped, stopping abruptly at the lateral fold. There are no enlarged papillae of any kind. The ventral mantle is densely covered in chromatophores. The hectocotylized arm bears 23–25 suckers. Ink sac and anal flaps are absent.

Description

Based on specimens detailed in Table 6. Animals small, ML to 43 mm, TL to 105 mm ( Fig. 6A ). Mantle spherical to ovoid ( MWI 94.5 ± 7.8), head narrower than mantle ( HWI 71.3 ± 8.0). Web deep ( WDI 41.1 ± 5.6), web formula approximately B = C = D.A = E. Funnel medium-sized (FuLI 47.2 ± 5.5), gently tapered; funnel organ W- or V-shaped. Gills with 6–8 lamellae per demibranch. Arms short ( MAI 73.4 ± 6.4). Arm lengths subequal, arm order usually 2 = 3 = 4.1 ( ALI L1123.7 ± 8.6; L2128.9 ± 5.8; L3128.6 ± 10.0; L4131.8 ± 11.7). Suckers uniserial, small to medium ( ASI 6.6 ± 0.9), without sucker enlargement. Third right arm of males hectocotylized, approximately equal to or longer than opposite number ( OAI 105.2 ± 5.2). Ligula moderate to large ( LLI 10.4 ± 1.4); ligula groove long, well-marked and shallow, without transverse ridges ( Fig. 6B ). Calamus distinct and large to very large (CaLI 49.2 ± 7.1). Hectocotylized arm with 23–25 suckers, opposite arm with up to 36 suckers. Penis diverticulum coiled. Spermatophores medium to long (SpLI 118.6 ± 15.3) and slender. Mature ovarian eggs large (> 10 mm). Ink sac absent. Anal flaps absent. Radula with nine elements, rachidian multicuspid ( Fig. 10F ). Other features of digestive and reproductive systems greatly resemble those of P. charcoti .

Papillae are compound, although they are not as large and elaborate as those of P. cornuta and their structure may be hard to discern in fixed material ( Fig. 9F ). They cover the entire dorsal surface but stop abruptly at the lateral fold ( Fig. 6C ). The lateral fold is unmarked; there is no distinct division between the dorsal and ventral mantle surfaces, except the abrupt cessation of the papillae. Chromatophores continue beyond the lateral fold onto the surface of the ventral mantle. They cover the entire ventral surface at a density similar to that found on the dorsal surface. There are no enlarged papillae on the dorsal mantle surface. Leucophores may be present as a bar between the eyes and as other patches on the anterior dorsal mantle. Freshly dead and live specimens ( Fig. 11F ) both have a deep purple hue.

Type locality

South Shetland Islands. 61∞59¢S,60∞19¢W. 804–930 m. RV Polarstern, ANT XVII/3 , Stn 56/178–2, 02.v.2000 .

Distribution

South Shetland Islands, 61∞06¢-62∞19¢S, 56∞07¢- 60∞48¢W, 427–804 m (this study).

Etymology

From the Greek pan (everywhere) and chromus (colour); refers to the intense coloration that covers the entire animal.

Remarks

This species lacks an ink sac and under the traditional scheme proposed by Voss (1988) would be placed in the Graneledone . However, it is now widely recognized that lack of an ink sac is a degenerate character associated with increasing depth (e.g. Allcock et al., 2003) and the other characteristics described above clearly indicate that this species belongs in Pareledone .

PARELEDONE SERPERASTRATA SP. NOV.

( FIGS 7A–C , 9G , 10G , 11G, TABLE 7)

Pareledone sp. 2 . – Piatkowski et al., 1998: 43 Pareledone sp. 26. – Piatkowski et al. 2003. – Allcock, 1997: 810, pl. 4.1.

Material examined

Holotype: NMSZ 2003152.003 , RV Polarstern, stn 61/ 092–1, 9.ii.2002, 61∞01¢S, 55∞46¢W, 123–159 m: 1♂ mature 36 [38] mm ML.

Paratypes: NMSZ 2002037.020 , RV Polarstern, stn 61/045–1, 29.i.2002, 60∞59¢S, 55∞11¢W, 196–269 m: 1♀ submature 33 [38] mm ML. NMSZ 2002037.021 , RV Polarstern, stn 61/092–1, 9.ii.2002, 61∞01¢S, 55∞46¢W, 123–159 m: 2♀ submature 29 [30], 32 [32] mm ML. NMSZ 2002037.022 , RV Polarstern, stn 61/ 093–1, 9.ii.2002, 61∞01¢S, 55∞46¢W, 153–184 m: 1♀ immature 21 [21] mm ML, 2♀ submature 23 [25], 30 [31] mm ML. NMSZ 2002037.047 , RV Polarstern, stn 61/101–1, 13.ii.2002, 61∞49¢S, 58∞35¢W, 321–399 m: 1 specimen (sex undetermined) immature [11] mm ML.

Diagnosis

Papillae are round and very small. They continue briefly beyond the lateral fold. There is a single supraocular papilla over each eye, and a pattern of modified papillae on the dorsal mantle. The ventral mantle is creamy white. The hectocotylized arm bears approximately 26 suckers.

Description

Based on specimens detailed in Table 7. Animals small, ML to 36 mm, TL to 104 mm ( Fig. 7A ). Mantle approximately spherical ( MWI 98.9 ± 5.5), head narrower than mantle ( HWI 72.2 ± 8.5). Web deep ( WDI 35.9 ± 3.2), web formula approximately B = C = D.A = E. Funnel medium-sized (FuLI 44.7 ± 4.5), gently tapered; funnel organ W- or V-shaped. Gills with 6–8 lamellae per demibranch. Arms short ( MAI 62.5 ± 5.0). Arm lengths subequal, arm order usually 2 = 3 = 4.1 ( ALI L1149.6 ± 14.9; L2159.4 ± 10.8; L3158.2 ± 14.4; L4157.9 ± 13.3). Suckers uniserial, medium-sized ( ASI 9.2 ± 1.2), without sucker enlargement. Third right arm of males hectocotylized, shorter than opposite number ( OAI 95.2) in only mature male examined. Ligula moderate to large ( LLI 8.5); ligula groove long, well-marked and shallow, without transverse ridges ( Fig. 7B ). Calamus distinct and moderate to large (CaLI 30.0). Hectocotylized arm with 26 suckers, opposite arm with up to 32 suckers. Penis diverticulum coiled. Spermatophores long (SpLI 144.4) and slender. Mature ovarian eggs large (> 10 mm). Ink sac present. Anal flaps present. Radula with nine elements, rachidian multicuspid ( Fig. 10G ). Other features of digestive and reproductive systems greatly resemble those of P. charcoti .

Papillae are simple, round and extremely small ( Fig. 9G ). They cover the entire dorsal surface and continue over the lateral fold for a few millimetres ( Fig. 7C ). The lateral fold is marked by a close set line of papillae that apparently contain leucophores. The line extends both posteriorly and anteriorly. Chromatophores continue beyond the lateral fold onto the surface of the ventral mantle; they extend slightly further than the papillae. There is an enlarged supraocular papilla. There are other papillae that stand out, but this is due to the presence of leucophores in their tips rather than enlargement. These distinct papillae usually show a characteristic pattern. There are also small round patches of leucophores spaced regularly half-way down each arm, giving the animal the appearance of wearing knee bandages. In preserved specimens these areas appear pink. A band of denser chromatophores is found just below the head. A freshly dead specimen usually has a grey hue. Live specimens ( Fig. 11G ) are usually pinker.

Type locality

South Shetland Islands. 61∞01¢S, 55∞46¢W. 123–159 m. RV Polarstern, ANT XIX/3 , Stn 61/092–1, 09.ii.2002 .

Distribution

South Shetland Islands, 60∞49¢-62∞50¢S, 54∞34¢- 60∞49¢W, 130–454 m (this study).

Etymology

From the Latin serperastrum (bandages, kneesplints), referring to the regular arrangement of white patches on the arms of this species.

PARELEDONE SUBTILIS SP. NOV.

( FIGS 8A–C , 9H , 10H , 11H; TABLE 8)

Pareledone sp. 33. – Piatkowski et al. 2003.

Material examined

Holotype: NMSZ 2003152.004 , RV Polarstern, stn 61/ 047–1, 30.i.2002, 61∞04¢S, 54∞36¢W, 308–399 m: 1♂ mature 34 [36] mm ML.

Paratypes: NMSZ 2002037.026 , RV Polarstern, stn 61/047–1, 30.i.2002, 61∞04¢S, 54∞36¢W, 308–399 m: 1♀ immature [21] mm ML, 4♀ submature [28], [31], [34], [34] mm ML, 4♀ mature 36 [41], 35 [43], 39 [45], 43 [52] mm ML, 1♂ mature 27 [30] mm ML. NMSZ 2002037.027 , RV Polarstern, stn 61/103–1, 13.ii.2002, 61∞45¢S, 58∞02¢W, 257–296 m: 2♀ mature 39 [43], 44 [51] mm ML, 1♂ mature 31 [36] mm ML.

Diagnosis

Papillae appear simple and round to naked eye, but less regular under microscope. They stop abruptly at the lateral fold. There are no enlarged papillae of any kind. The ventral mantle is covered in chromatophores although these are less dense than on the dorsal surface. The hectocotylized arm bears approximately 24 suckers.

Description

Based on specimens detailed in Table 8. Animals small, ML to 44 mm, TL to 109 mm ( Fig. 8A ). Mantle spherical to ovoid ( MWI 91.2 ± 5.8), head narrower than mantle ( HWI 62.1 ± 6.2). Web deep ( WDI 40.2 ± 2.6), web formula approximately B = C = D.A.E. Funnel medium-sized (FuLI 45.8 ± 5.7), gently tapered; funnel organ W- or Vshaped. Gills with 6–8 lamellae per demibranch. Arms short ( MAI 70.1 ± 6.5). Arm lengths approximately equal ( ALI L1137.7 ± 12.6; L2143.0 ± 10.8; L3140.4 ± 12.1; L4139.9 ± 16.6). Suckers uniserial, small to medium ( ASI 6.9 ± 0.8), without sucker enlargement. Third right arm of males hectocotylized, usually shorter than opposite number ( OAI 94.5 ± 2.6). Ligula moderate to large ( LLI 10.0 ± 1.6); ligula groove long, well-marked and shallow, without transverse ridges ( Fig. 8B ). Calamus distinct and large to very large (CaLI 53.7 ± 3.2). Hectocotylized arm with approximately 24 suckers, opposite arm with up to 33 suckers. Penis diverticulum coiled. Spermatophores long (SpLI 124.3 ± 8.6) and slender. Mature ovarian eggs large (> 10 mm). Ink sac present. Anal flaps present. Radula with nine elements, rachidian multicuspid, cusps small, may appear unicuspid when worn ( Fig. 10H ). Other features of digestive and reproductive systems greatly resemble those of P. charcoti .

Papillae appear simple and round when viewed with the naked eye. They apparently resemble those of P. aequipapillae or P. aurata , although when viewed under the microscope they are slightly less regular in structure ( Fig. 9H ). The papillae cover the entire dorsal surface but stop abruptly at the lateral fold ( Fig. 8C ). The lateral fold is marked posteriorly by a slightly raised ridge, itself marked with leucophores. Anteriorly (towards the pallial aperture) there is no distinct division between the dorsal and ventral mantle surfaces, except the abrupt cessation of the papillae. Chromatophores continue beyond the lateral fold onto the surface of the ventral mantle. Here they are sparser; nonetheless they cover the entire ventral surface. There are no enlarged papillae on the dorsal mantle surface. Leucophores are apparent on and just below the head region and may also be present laterally. A freshly dead specimen usually has a purple hue. Live specimens ( Fig. 11H ) are usually paler.

Type locality

South Shetland Islands. 61∞04¢S, 54∞37¢W. 190 m. RV Polarstern, ANT XIX/3 , Stn 61/047–1, 30.i.2002 .

Distribution

South Shetland Islands, 61∞04¢-61∞45¢S, 54∞34¢- 58∞51¢W, 190–427 m (this study).

Etymology

From the Latin subtilis (fine-spun, delicate), referring to the delicate nature of the web.

Figures

Figure 1. Pareledone charcoti Joubin, 1905. A, whole animal, NMSZ 2002037.044, mature ♂, 37 mm ML. B, hectocotylus, NMSZ 2002037.044, mature ♂, 37 mm ML. C, diagrammatic representation of extent of papillae and chromatophores. Abbreviations: leu, leucophores; sop, supraocular papillae. D, digestive system, NMSZ 2002037.044, submature ♀, 33 mm ML. E, beaks, NMSZ 2002037.044, submature ♀, 33 mm ML. F, male reproductive system, NMSZ 2002037.044, mature ♂, 36 mm ML. G, spermatophores, NMSZ 2002037.044, mature ♂, 36 mm ML. H, female reproductive system, NMSZ 2002037.044, mature ♀, 43 mm ML. I, transverse section of egg showing follicular folds. Scale bars = 5 mm.

Figure 2. Pareledone aequipapillae sp. nov. A, whole animal, NMSZ 2002037.004, submature ♀, [34] mm ML. B, hectocotylus, NMSZ 2003152.002, mature ♂, 52 mm ML, scale bar = 5 mm. C, diagrammatic representation of extent of papillae and chromatophores: ep, enlarged papillae; leu, leucophores; sop, supraocular papilla.

Figure 3. Pareledone albimaculata sp. nov. A, whole animal, NMSZ 2002037.011, submature ♀, 29 mm ML. B, hectocotylus, NMSZ 2002037.010, mature ♂, 36 mm ML, scale bar = 5 mm. C, diagrammatic representation of extent of papillae and chromatophores: sop, supraocular papilla.

Figure 4. Pareledone aurata sp. nov. A, whole animal, NMSZ 2003152.001, mature ♂, 41 mm ML. B, hectocotylus, NMSZ 2003152.001, mature ♂, 41 mm ML, scale bar = 5 mm. C, diagrammatic representation of extent of papillae and chromatophores: leu, leucophores; sop, supraocular papilla.

Figure 5. Pareledone cornuta sp. nov. A, whole animal, NMSZ 2002037.018, mature ♀, 47 mm ML. B, hectocotylus, NMSZ 2002037.018, mature ♂, 38 mm ML, scale bar = 5 mm. C, diagrammatic representation of extent of papillae and chromatophores: ep, enlarged papillae; leu, leucophores; sop, supraocular papilla.

Figure 6. Pareledone panchroma sp. nov. A, whole animal, NMSZ 2002037.023, mature ♂, [28] mm ML. B, hectocotylus, NMSZ 2003152.005, mature ♂, 33 mm ML, scale bar = 5 mm. C, diagrammatic representation of extent of papillae and chromatophores.

Figure 7. Pareledone serperastrata sp. nov. A, whole animal, NMSZ 2002037.021, submature ♀, 29 mm ML. B, hectocotylus, NMSZ 2003152.003, mature ♂, 36 mm ML, scale bar = 5 mm. C, diagrammatic representation of extent of papillae and chromatophores: mp, modified papillae; sop, supraocular papilla.

Figure 8. Pareledone subtilis sp. nov. A, whole animal, NMSZ 2002037.026, submature ♀, [31] mm ML. B, hectocotylus, NMSZ 2003152.004, mature ♂, 34 mm ML, scale bar = 5 mm. C, diagrammatic representation of extent of papillae and chromatophores: leu, leucophores.

Figure 9. Papillae structure as seen under a stereomicroscope. Width of photograph encompasses 5 mm of tissue. A, Pareledone charcoti Joubin, 1905, NMSZ 2002037.044. B, P. aequipapillae sp. nov., NMSZ 2002037.004. C, P. albimaculata sp. nov., NMSZ 2002037.011. D, P. aurata sp. nov., NMSZ 2002037.003. E, P. cornuta sp. nov., NMSZ 2002037.018. F, P. panchroma sp. nov., NMSZ 2000081.051. G, P. serperastrata sp. nov., NMSZ 2002037.022. H, P. subtilis sp. nov., NMSZ 2002037.027.

Figure 10. Radulae. A, Pareledone charcoti Joubin, 1905. B, P. aequipapillae sp. nov. C, P. albimaculata sp. nov. D, P. aurata sp. nov. E, P. cornuta sp. nov. F, P. panchroma sp. nov. G, P. serperastrata sp. nov. H, P. subtilis sp. nov.

Figure 11. Live animals. A, Pareledone charcoti Joubin, 1905, NMSZ 2002037.044. B, P. aequipapillae sp. nov., NMSZ 2002037.004. C, P. albimaculata sp. nov., NMSZ 2002037.011. D, P. aurata sp. nov., NMSZ 2002037.003. E, P. cornuta sp. nov., NMSZ 2002037.018. F, P. panchroma sp. nov., NMSZ 2000081.051. G, P. serperastrata sp. nov., NMSZ 2002037.022. H, P. subtilis sp. nov., NMSZ 2002037.027.

Figure 12. Depth distribution of eight species of Pareledone. The 5% deepest and 5% shallowest specimens of each species are excluded. Lines represent next 20% shallowest and 20% deepest specimens. Solid bars represent the middle depth bands inhabited by each species, from which 50% of specimens were captured.