Epimeria (Drakepimeria) corbariae, d’Acoz & Verheye, 2017

d’Acoz, Cédric d’Udekem & Verheye, Marie L., 2017, Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea), European Journal of Taxonomy 359, pp. 1-553 : 33-36

Epimeria (Drakepimeria) corbariae sp. nov.

urn:lsid:zoobank.org:act:74519DD0-1C75-4392-AA0D-5FB811B108F4

Figs 27–43

Epimeria macrodonta –? Chilton 1912: 486.

‘Clade A similis / macrodonta complex - MA2ʹ – Verheye et al. 2016a, supplement: 2 (online).

non Epimeria macrodonta Walker, 1906: 16 .

Etymology

The species is dedicated to Laure Corbari (Muséum national d’Histoire naturelle, Paris), who gave us the opportunity to study the very interesting collections of the CEAMARC and REVOLTA expeditions. The name is a genitive.

Type material

Holotype

REVOLTA cruises: ( RV Seatruck)

SOUTHERN OCEAN: 1 ♀, cruise REVOLTA I, stn REVO-007b, Collect_ ID: 249, Field_ ID: CE- 000004589, Adélie Coast, 66°38ʹ25″ S, 139°49ʹ43″ E, 127–133 m, 22 Jan. 2010, coll. M. Eléaume, L.

Hemery and A. D’Hont, (MNHN-IU- 2009-2570) [extraction K 4; Genbank nr, COI: KU 870872 , 28 S: KU 759652 ].

Paratypes

RV Aurora Australis cruises:

SOUTHERN OCEAN: 3 specs, cruise CEAMARC, sample CEAMARC 933, stn 40EV152, Adélie Coast, 66°39ʹ38″ S, 143°01ʹ16″ E, 471–637 m, beam trawl, 28 Dec. 2007, coll. IPEV-AAD-MNHN (MNHN-IU-2014-4283); 1 ♀, cruise CEAMARC, sample CEAMARC 1643, stn 31EV268,Adélie Coast, 66°34ʹ30″ S, 145°01ʹ15″ E, 429–451 m, beam trawl, 3 Jan. 2008, coll. IPEV-AAD-MNHN ( MNHN- IU-2014-7326, removed from MNHN-IU-2014-4322); 5 specs, cruise CEAMARC, sample CEAMARC 2072, stn 65EV322, Adélie Coast, 65°48ʹ29″ S, 143°03ʹ46″ E, 750–788 m, beam trawl, 5 Jan. 2008, coll. IPEV-AAD-MNHN (MNHN-IU-2014-4286); 1 ♀, cruise CEAMARC, sample CEAMARC 2724, stn 71EV447, Adélie Coast, 66°24ʹ00″ S, 140°32ʹ21″ E, 683–791 m, v 14 Jan. 2008, coll. IPEV-AAD- MNHN (MNHN-IU-2014-7327, removed from MNHN-IU-2014-4337); 6 specs, cruise CEAMARC, sample CEAMARC 3978, stn 36EV297, Adélie Coast, 66°20ʹ20″ S, 143°41ʹ08″ E, 552–573 m, beam trawl, 4 Jan. 2008, coll. IPEV-AAD-MNHN (MNHN-IU-2014-4330); 1 spec., cruise REVOLTA II, stn REVO_133, Collect_ ID: REVO_133, Adélie Coast, 66°37ʹ04″ S, 140°00ʹ13″ E, 103–107 m, 11 Jan. 2011, coll. N. Améziane, N. Bax, C. Gallut, A. C. Lautrédou and C. Robineau (MNHN-IU-2014-4297); 1 ovigerous ♀, cruise REVOLTA II, stn REVO_091, Collect_ ID: REVO_162, Field_ ID: CE-000001166, Adélie Coast, 66°41ʹ07″ S, 139°56ʹ41″ E, 33–34 m, 19 Jan. 2011, coll. N. Améziane, N. Bax, C. Gallut, A. C. Lautrédou and C. Robineau (MNHN-IU-2014-7325, removed from MNHN- 2014-4299) [extraction M 10; Genbank nr, COI: KU 870878 , 28 S: KU 759661 ]; 1 spec., cruise REVOLTA II, stn REVO_091, Collect_ ID: REVO_162, Field_ ID: CE-000001166, 66°41ʹ07″ S, 139°56ʹ41″ E, 33–34 m, 19 Jan. 2011, coll. N. Améziane, (MNHN-IU-2014-4299); 1 spec., cruise REVOLTA II, stn REVO_091, Collect_ ID: REVO_162, Adélie Coast, 66°41ʹ07″ S, 139°56ʹ41″ E, 33–34 m, 19 Jan. 2011, coll. N. Améziane, N. Bax, C. Gallut, A. C. Lautrédou and C. Robineau (MNHN-IU-2014-4298); 1 juv., cruise REVOLTA II, stn REVO_085, Collect_ ID: REVO_191, Field_ ID: CE-000001559, 66°40ʹ12″ S, 139°55ʹ56″ E, Adélie Coast, 37–44 m, 29 Jan. 2011, coll. N. Améziane, N. Bax, C. Gallut, A. C. Lautrédou and C. Robineau, (MNHN-IU-2014-4296) [extraction M 11; Genbank nr, 28 S: KU 759662 ]; 1 spec., cruise REVOLTA II, stn REVO_037, Collect_ ID: REVO_209, Adélie Coast, 66°39ʹ13″ S, 139°52ʹ04″ E, 105–107 m, 1 Feb. 2011, coll. N. Améziane, N. Bax, C. Gallut, A. C. Lautrédou and C. Robineau (MNHN-IU-2014-4305); 2 specs, cruise REVOLTA II, stn REVO_037, Collect_ ID: REVO_209, Adélie Coast, 66°39ʹ13″ S, 139°52ʹ04″ E, 105–107 m, 1 Feb. 2011, coll. N. Améziane, N. Bax, C. Gallut, A. C. Lautrédou and C. Robineau ( RBINS 132717, formerly MNHN-IU-2014-4305); 1 spec., cruise REVOLTA III, stn REVO_039, Collect_ ID: REVO_464, Adélie Coast, 66°38.370ʹ S, 139°55.863ʹ E to 66°38.406ʹ S, 139°56.030ʹ E, 100 m, beam trawl, 30 Jan. 2012, coll. G. Lecointre, A. Dettaï, J. Lanshere, C. Gallut and C. Ozouf ( MNHN number-IU- 2009-2542); 1 juv., cruise REVOLTA III, stn REVO_040, Collect_ ID: REVO_470, Adélie Coast, 66°38.50ʹ S, 139°57.02ʹ E to 66°38.41ʹ S, 139°57.14ʹ W, 98–100 m, beam trawl, 31 Jan. 2012, coll. G. Lecointre, A. Dettaï, J. Lanshere, C. Gallut and C. Ozouf ( MNHN- IU- 2009-2551); 1 small spec., cruise REVOLTA III, stn REVO_064, Collect_ ID: REVO_481, Adélie Coast, 66°36.371ʹ S, 140°05.075ʹ E to 66°36.394ʹ S, 140°04.966ʹ E, 110–120 m, beam trawl, 3 Jan. 2012, coll. G. Lecointre, A. Dettaï, J. Lanshere, C. Gallut and C. Ozouf (MNHN-IU- 2009-2562); 1 adult spec., cruise REVOLTA III, stn REVO_068, Collect_ ID: REVO_493, Field_ ID: CE-000002621, Adélie Coast, 66°35ʹ18″ S, 140°03ʹ15″ E to 66°35ʹ22″ S, 140003ʹ23″ E, 57–118 m, beam trawl, 7 Feb. 2012, coll. G. Lecointre, A. Dettaï, J. Lanshere, C. Gallut and C. Ozouf (MNHN-IU- 2009-2581).

RV L’Astrolabe cruises:

5 specs, cruise REVOLTA III, stn none (Dumont d’Urville sea), Collect_ ID: REVO _449, Field_ ID: CE-000002109 Adélie Coast, 66°38ʹ S, 140°42ʹ E to 66°38ʹ S, 140°40ʹ E, 718–729 m, mud, beam trawl, 20 Jan. 2012, coll. G. Lecointre, A. Dettaï, J. Lanshere, C. Gallut and C. Ozouf (MNHN-IU- 2009-2543); 1 ♀, cruise REVOLTA III, stn REVO_064, Collect_ ID: REVO _481, Field_ ID: CE-000003196, Adélie Coast, 66°36.371ʹ S, 140°05.075ʹ E to 66°36.394ʹ S, 140°04.966ʹ E, 110–120 m, beam trawl, 3 Feb. 2012, coll. G. Lecointre, A. Dettaï, J. Lanshere, C. Gallut and C. Ozouf (MNHN-IU- 2009-2563) [extraction K 5; Genbank nr, COI: KU 870876 , 28 S: KU 759657 ].

Description

ROSTRUM. Long, reaching base of article 2 of peduncle of antenna 1 (teeth excluded), very strongly curved, sharp-tipped in lateral view.

EYE. Large, broadly elliptic.

PEREION–PLEOSOME TOOTH PATTERN. Pereionite 1 usually without mid-dorsal tooth or with a posterior bump, rarely with small subacute tooth pointing upwards (tooth with anterior border oblique and posterior border vertical), without pair of dorsolateral protrusions when pereionite has no mid-dorsal tooth or only a posterior bump, with pair of low protrusions when mid-dorsal tooth present; pereionite 2 much narrower than pereionites 1 and 3, without mid-dorsal tooth and without pair of dorsolateral teeth; pereionite 3 with medium-sized, broad, subacute to acute tooth pointing upwards or slightly backwards and pair of low and blunt, conical, dorsolateral teeth; pereionite 4 to pleonite 2 with large, narrow to fairly narrow, acute mid-dorsal tooth, of which the anterior border is regularly curved or curved with very faint angular discontinuity and the posterior border is slightly concave, with pair of conical dorsolateral teeth of which the size gradually increases posteriorly (these pairs of teeth are never duplicate); pleonite 3 with large nearly styliform acute-tipped symmetrical mid-dorsal tooth, and pair of large narrowly conical dorsolateral teeth (size of mid-dorsal teeth weakly increasing from pereionite 4 to pleonite 2; mid-dorsal tooth of pleonite 3 slightly but distinctly shorter than tooth of pleonite 2).

COXAE 1–3. Strongly carinate and distally sharp.

COXA 4. Anterodorsal border straight, anteroventral border distally slightly curved, these two borders being joined by a fairly short blunt angular discontinuity (anterior angle), this anterior angle is weakly projecting forward; ventral tooth long and acute; lateral carina with small tooth pointing backwards (its anterior border is parallel to body axis or nearly so; in dorsal view this tooth form a narrow V-shaped notch with the coxa); carina fairly distant from margin of coxa at its deepest point.

COXA 5. With long, sharp, narrowly triangular, carinate, lateral tooth pointing backwards (its anterior margin is distinctly oblique to nearly parallel to body axis and its posterior margin is oblique.

COXA 6. With mid-sized, sharp and triangular, carinate, lateral tooth pointing obliquely backwards; its anterior border is distinctly convex); posteroventral corner broadly rounded.

COXA 7. With ventral border slightly curved, with posterior border straight or very weakly concave, their convergence forming a sharp squared angle.

EPIMERAL PLATES 1–3. Posteroventral angle produced into a very long and very sharp tooth.

UROSOME TOOTH PATTERN. Urosomite 1 with large and sharp narrow tooth pointing upwards; urosomite 2 with pair of mid-sized posterior dorsolateral teeth pointing upwards; urosomite 3 with pair of mid-sized posterior dorsolateral teeth pointing obliquely upwards.

TELSON. Cleft on 0.45–0.55; tips of lobes subacute, notch narrowly U-shaped. PEDUNCLE OF ANTENNA 1. Article 1 with long lateral and medial teeth reaching mid of article 2 (teeth excluded) and long ventral tooth distinctly overreaching tip of article 2 (teeth excluded); article 2 with large lateral tooth of which 0.3 is overreaching tip of article 3, and huge medial teeth of which 0.6 is overreaching tip of article 3, without ventral tooth; article 3 with medium-sized ventral tooth, about 0.3 times as long as article itself.

GNATHOPODS 1–2. Carpus and propodus of normal slenderness; very slightly broadening distally, palm distinct.

PEREIOPODS 5–7. Merus, carpus and propodus slender; basis of pereiopods 5–6 of normal width, with posteroproximal process rounded and strongly protruding, with posterodistal tooth very strong (as long as basis width); basis of pereiopod 7 broad with posterodistal tooth acute and large, followed more proximally by distinct concavity, directed posteriorly.

Colour pattern

Homogeneously bright red, or red marks on a whitish or pale reddish background.

Body length

Up to 31 mm.

Distribution

Adélie Coast, 33– 827 m.

Remarks

Epimeria corbariae sp. nov. exhibits variation in the dentition of the first body segment and the robustness of the mid-dorsal teeth (see figs 27, 28, 34, 38). The angle of divergence of the lateral tooth of coxa 5 with body axis is also variable. Due to these variations, the most extreme forms of E. corbariae sp. nov. were initially interpreted as two separate species. However, genetic data (COI, 28S) suggest that they are indeed conspecific ( Fig. 342 ). Epimeria corbariae sp. nov. (Adélie Coast) is morphologically similar to E. anguloce sp. nov. (Weddell Sea and Bransfield Strait), but molecular analyses based on the 28S gene suggest that they are distinct species ( Fig. 342 ). The following morphological differences were observed. In E. corbariae sp. nov., pereionite 1 is usually smooth or with a posterior bump (rarely with a small tooth); in E. anguloce sp. nov. a small tooth is always present. In E. corbariae sp. nov. the mid-dorsal tooth of pereionite 3 to pleonite 2 are a bit shorter and a bit broader than in E. anguloce sp. nov. and those of pereionite 3 to pleonite 2 have a trace of anterior angular discontinuity, which is not present in E. anguloce sp. nov. The tooth of the lateral carina of coxa 4 is more posteriorly directed in E. corbariae sp. nov. and forms a narrower notch with the coxa (when examined in dorsal view) than in E. anguloce sp. nov. The junction between the ventral and the posterior border of coxa 7 forms a sharp squared angle in E. corbariae sp. nov. vs a blunt squared angle in E. anguloce sp. nov., this difference being very clear. In E. corbariae sp. nov., the posterodistal tooth of basis of pereiopod 7 is shorter than in E. anguloce sp. nov. Epimeria corbariae sp. nov. is also very similar to E. schiaparelli , but the middorsal ornamentation of pereionite 3 is much more developed in the first species.

Figures

Fig. 27. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., paratypes, Adélie Coast. Colour in life. A. CE- REVOLTA III, Collect_ID: REVO_449, CE-000002109, MNHN-IU-2009-2543. B. REVOLTA III, stn REVO_068, Collect_ID: REVO_493, CE-000002621, MNHN-IU-2009-2581. C. REVOLTA II, stn REVO_085, Collect_ID: REVO_191, CE-000001559, MNHN-IU-2014-4296. Photographs: Cyril Gallut (Université Pierre et Marie Curie).

Fig. 28. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, holotype, Adélie Coast, REVOLTA I, REVO-007b, sample 249, MNHN-IU-2009-2570. A. Lateral habitus. B. Dorsal habitus. Note the absence of mid-dorsal tooth on the first body segment.

Fig. 29. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, holotype, Adélie Coast, REVOLTAI, REVO-007b, sample 249, MNHN-IU-2009-2570. A. Head in facial view. B. Facial habitus.

Fig. 30. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, holotype, Adélie Coast, REVOLTA I, REVO-07b, sample 249, MNHN-IU-2009-2570. A. Coxae. B. Coxa 7 and posterior half of coxa 6. C. Urosome and pleonite 1.

Fig. 31. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, holotype, Adélie Coast, REVOLTA I, REVO-07b, sample 249, MNHN-IU-2009-2570. A. Head in lateral view. B. Urosome in dorsal view. C. Telson.

Fig. 32. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, holotype, Adélie Coast, REVOLTA I, REVO-07b, sample 249, MNHN-IU-2009-2570. A. Gnathopod 1. B. Gnathopod 2.

Fig. 33. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, holotype, Adélie Coast, REVOLTA I, REVO-07b, sample 249, MNHN-IU-2009-2570. A. Pereiopod 4. B. Pereiopod 5. C. Pereiopod 6. D. Pereiopod 7.

Fig. 34. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, REVO 481, MNHN-IU-2009-2563. A. Lateral habitus. B. Dorsal habitus. Note the presence of a trace of mid-dorsal tooth on the first body segment. C. ♀♀, paratypes, Adélie Coast, REVOLTA II, stn REVO 162, MNHN- IU-2014-7325, colour in life, photograph Cyril Gallut (Université Pierre et Marie Curie).

Fig. 35. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, collect nr REVO_481, MNHN-IU-2009-2563. A. Facial habitus. B. Head in facial view.

Fig. 36. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, collect nr REVO_481, MNHN-IU-2009-2563. A. Coxae. B. Urosome.

Fig. 37. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, collect nr REVO_481, MNHN-IU-2009-2563. A. Head in lateral view. B. Urosome in dorsal view.

Fig. 38. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, REVO 162, MNHN-IU-2014-7325. A. Lateral habitus. B. Dorsal habitus. Note the presence of a well-developed mid-dorsal tooth (and of a pair of weak dorsolateral teeth) on the first body segment; the wider projections broader and the body broader in lateral view than for the two other illustrated specimen. This morphological variant is unfrequent.

Fig. 39. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, REVO 162, MNHN-IU-2014-7325. A. Facial habitus. B. Head in facial view

Fig. 40. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, REVO 162, MNHN-IU-2014-7325. A. Coxae. B. Coxae 6–7. C. Urosome.

Fig. 41. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, REVO 162, MNHN-IU-2014-7325. A. Head in lateral view. B. Urosome in dorsal view.

Fig. 42. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, REVO 162, MNHN-IU-2014-7325. A. Gnathopod 1. B. Gnathopod 2.

Fig. 43. Epimeria (Drakepimeria) corbariae subgen. et sp. nov., ♀, paratype, Adélie Coast, REVO 162, MNHN-IU-2014-7325. A. Pereiopod 4. B. Pereiopod 5. C. Pereiopod 6. D. Pereiopod 7.

Fig. 342. Phylogenetic tree obtained by Bayesian analysis of the concatenated COI and 28S sequences, updated from Verheye et al. (2016). Bayesian posterior probabilities and bootstrap values (from the Maximum Likelihood analysis) are indicated above the nodes of interest. Bootstrap values inferior to 50 are not indicated. Besides the species names are indicated the MOTUs codes used in Verheye et al. (2016). The Genbank accession number of the outgroup species: Gnathiphimedia sexdentata (Schellenberg, 1926) are KU870835 (COI) and KU759609 (28S).