Haplocheira barbimana robusta K.H. Barnard, 1932

Coleman, Charles Oliver, Krapp-Schickel, Traudl & Häussermann, Vreni, 2022, Amphipod crustaceans from Chilean Patagonia, European Journal of Taxonomy 849 (1), pp. 1-57 : 12-20

Haplocheira barbimana robusta K.H. Barnard, 1932

Figs 7–11

Synonymy, amended after De Broyer et al. (2007):

Haplocheira robusta K.H. Barnard, 1932: 235 , fig. 148.

Haplocheira barbimana ( Thomson, 1879) as Gammarus barbimanus : 230–248, pl. 10.

Haplocheira barbimanus ? – Stebbing 1914: 370 (questioned by Nicholls 1938).

Haplocheira barbimanus – Schellenberg 1931: 232. — Nicholls 1938: 127 (in part). — J.L. Barnard 1958: 113 (in part); 1972: 25 (in key), 130 (in part). — Gonzalez 1991: 53. — De Broyer & Jażdżewski 1993: 30. — Chiesa et al. 2005: 170.

Haplocheira robusta – Lowry & Bullock 1976: 33 (in part). — Moore & Myers 1983: 212–213, figs 18– 20, 22. — J.L. Barnard & Karaman 1991: 197.

Haplocheira barbimana robusta – Moore & Myers 1983: 212–213, figs 18–20, 22. — Chiesa et al. 2005: 170, tb. 2, 172, tb. 3. — De Broyer et al. 2007: 242.

Material examined

CHILE • 1 ♂ (4.2 mm); Isla Allen SE; -44.03486666°, -74.1894°; 5 m depth; 11 Apr. 2014; 260HF21; wood; ZMB 34098 ( Figs 7–11 ) • 8 specs; Bahia Edwards; -45.91555°, -73.66136666°; 3 m depth; 17 Apr. 2014; 609HF21; with stones; ZMB 34097 .

Description (based on ♂, 4.2 mm)

BODY ( Fig. 7a ). Head longer than deep, as long as first two pereonites, anterior head lobe rounded, eyes oval. Pereonites 1–5 subequal in length, pereonite 6 shortest, pereonite 7 longest. Pleonites 1 and 2 subequal in length, pleonite 3 longest; posteroventral angle of epimeron of pleonite 1 ( Fig. 7a ) with short point, that of pleonites 2 and 3 roundly angular and with slender setae on the lateral face along the ventral margin. Urosomite 1 longest; urosomites 2 and 3 equally long.

HEAD APPENDAGES. Antenna 1 ( Fig. 7c ) shorter than antenna 2; peduncle articles 1–3 narrowing, length ratios 1: 0.8: 0.38;accessory flagellum biarticulate, first article overreaches 1 st article of primary flagellum, very short second article terminally (14% of 1 st article), with a tuft of apical setae; primary flagellum with 7 articles, 5 apical articles with 1 aesthetasc each and several short setae. Antenna 2 ( Fig. 7d ) peduncle article 1 scale-like; article 2 with narrow produced nephridial cone; article 3 subquadrate; article 4 and 5 subrectangular, peduncular length ratios 1:0.9: 2: 3.4: 2.8; flagellum of 3 articles, aside from slender setae a pair of robust setae on distal margin of each flagellum article. Mandible ( Fig. 7b, e ) with strongly produced molar column, triturative molar surface; row of stout rakers; lacinia mobilis and incisor multidentate; palp 3-articulate; article 1 with 1 distal slender seta; article 2 slightly curved, with 2 long mediomarginal setae and two thin setae; article 3 straight, distally rounded with a tuft of long slender setae; length ratios of article 1–3: 1: 1.3: 0.9. Lower lip (hypopharynx) ( Fig. 7g ) with rounded inner lobes and wide distal lobes and short mandibular processes. Maxilla 1 ( Fig. 8a ) inner plate with 10 long plumose setae on apicomedial margin; outer plate with 8 robust setae distomarginally; palp 2-articulate with short 1 st article and long distal article, longer than outer plate, with 5 robust setae distally and group of slender, plumose setae submarginally. Maxilla 2 ( Fig. 10d ) outer lobe slightly longer and narrower (80%) than inner lobe; inner lobe apart from terminal setae with additional setal row subapically on face and along medial margin. Maxilliped inner plate ( Fig. 8b ) slightly expanded distally, truncate apically, with plumose setae along medial margin and apically; outer plate ( Fig. 8c ) narrow, lanceolate with few robust setae medioapicomarginally and two setulated setae on the outer distal margin; palp ( Fig. 8d ) 4-articulate, length ratios: 1: 2: 1.15: 0.7; palp article 1 distally oblique; article 2 weakly convex on both margins, inner margin with a row of long slender marginal setae and another row of submarginal setae; article 3 weakly expanded distally with long setation in apical half; article 4 tapering distally, rounded tip and some medioapical setae.

PEREON. Gnathopod 1 ( Fig. 9a ) coxa subrectangular, rounded ventrally; basis about the length of coxa, with some long setae posteromarginally; ischium wider than long; merus 2× the length of ischium, tapering into a narrow process; carpus expanded distally with a row of long slender setae on the medial face, posterior margin with a row of similar setae; propodus longer and narrower than carpus with setation on both margins, posterodistally drawn out into a tooth; dactylus falcate with a pointed process on the distal ⅔ of the inner curvature. Gnathopod 2 ( Fig. 9b ) coxa subrectangular with a fringe of setae ventromarginally; basis as long as coxa with some long setae posteromarginally; ischium wider than long, apically oblique; merus subrectangular with row of setae on distal margin; carpus subrectangular with row of long slender setae along posterior margin and diagonal on medial face; propodus slightly tapering distally, long slender setae on both margins; dactylus weakly falcate. Pereopods 3 and 4 ( Fig. 10a, c ) coxa subrectangular, ventral margin rounded with fringe setae; basis posteromarginally roundly expanded; ischium slightly wider than long; merus posterodistally expanded; carpus ovoid, longer than wide; propodus tapering distally; dactylus only weakly curved; length ratios ischium to dactylus 1: 2.3: 1.4: 2:1.6. Pereopod 5 ( Fig. 10b ) coxa bilobate, anterior lobe 2.2× as long as posterior lobe, overlapping anterior ⅓ of basis; basis as long as wide, anterior margin convex, proximoposterior rounded lobe; ischium 2× as wide as long; merus subrectangular; carpus shorter than merus, subrectangular with robust setae antero- and posterodistally; propodus tapering distally with robust setae on lateral face; dactylus straight; length ratios ischium to dactylus: 1:2: 1.6: 2.5: 1.1. Pereopod 6 ( Fig. 11a ) coxa bilobed, anterior lobe narrower and slightly longer than posterior shallow lobe; basis ovoid, anterior and margins convex, posteroventral lobe shorter than distal ischium margin; ischium 1.9 × as wide as long; anteroventral angle of basis and ischium and anterior margin of merus with long slender setae; merus posteroventral angle slightly drawn out; carpus subrectangular; propodus tapering distally, with groups of robust setae on the lateral face; dactylus rather straight; postero- and anteroventral angles of merus and carpus with robust setae; length ratios of ischium to dactylus: 1: 2.2: 2: 2.7: 1.3. Pereopod 7 ( Fig. 11b ) coxa 2.2× as wide as long, oblique anteriorly, rounded posteriorly; basis similar to that pereopod 6, but posteroventral lobe wider and longer than distal ischium margin and proximoposteromarginally narrower; ischium 1.7× as wide as long; merus to propodus as for pereopod 6; dactylus strongly falcate.

PLEON AND UROSOME. Pleopod 1 ( Fig. 11d ) peduncle subquadrate, mediodistal angle drawn out, 2 coupling hooks, outer ramus shorter than inner (77%). Uropod 1 ( Fig. 11c ) peduncle 1.3 × as long as wide, about the length of outer ramus, with long pointed ventral process; some robust setae on outer margin and 1 on the mediodistal angle; outer ramus somewhat shorter than the inner, with robust setae on both margins and apically, inner ramus with robust setae on the medial margin and apically. Uropod 2 ( Fig. 11e ) peduncle longer than rami, outer ramus less than half the length of peduncle; inner ramus 1.4× the length of outer ramus, both rami with a group of terminal setae, 1 additional seta on the margin of the outer ramus and 2 on the dorsal face of the inner ramus. Uropod 3 ( Figs 10e , 11f ) peduncle subquadrate, outer ramus short with a group of apical setae, inner ramus scale-like with 1 terminal robust seta. Telson ( Fig. 10e ) tapering, 1.4× as wide as long, entire and rounded.

Distribution (amended after De Broyer et al. 2007)

Falkland Islands: East Falkland Island, Port Stanley, low water (bottom/habitat: in seaweed and in a sponge) ( Stebbing 1914); Port Albemarle, 40 m (bottom/habitat: sand, algae); Berkeley Sound, 16 m (bottom/habitat: gravel, shells, algae); Port William, 22 m (bottom/habitat: sand); Port Louis, 3–4 m (bottom/habitat: shells, stones); Sparrow Cove, 11–13 m (bottom/habitat: shells) ( Schellenberg 1931); Discovery 1925–27, stn 53, East Falkland Island, Port Stanley, 0–2 m (bottom/habitat: kelp roots); stn 54, East Falkland Island, Port Stanley, shore; stn 58, East Falkland Island, Port Stanley, piles of jetty, 1–2 m (gear: mussel rake); stn WS 71, East Falkland Island, NE of Cape Pembroke, 82 m (bottom: sand; gear: commercial otter trawl); stn WS 85, SE of Lively Island, 79 m (bottom: sand, shells; gear: commercial otter trawl) (K.H. Barnard 1932).

Magellan Province: Ultima Esperanza, 13–18 m (bottom/habitat: algae, clay, stones); Bahia Inutil, 36–54 m (bottom/habitat: shells); Punta Arenas, 27 m (bottom/habitat: shells); Rio Seco, 18–36 m (bottom/habitat: shells); Puerto Madryn, 4–10 m (bottom/habitat: sand, clay); Isla Larga, Canal Smith, 14 m; Puerto Bueno; Bahia Ushuaia, 0–4 m; Banco Sarmiento, -52.4°, -68.15°, 22 m; -54.716667°, -64.133333°, 36 m (bottom/habitat: pebble, gravel) ( Schellenberg 1931); Discovery 1925–27, stn WS 86, -53.883333°, -60.566667°, 147–151 m (bottom/habitat: sand, shells, stones; gear: commercial otter trawl) (K.H. Barnard 1932); Hudson 70, Southern Chile, Punta Wulaia, low water reef; Cabo de Hornos: stn F24, stn F12, stn 722 ( Moore & Myers 1983); Punta Arenas; Bahia Inutil ( Gonzalez 1991); southern Tierra del Fuego, Ushuaia, -54.816667°, -68.266667°; Isla Gable, -54.9°, -67.35°, 15–20 m (gear: dredge); Punta Moat, -55.033333°, -66.7°, 15–25 m (gear: dredge); Cabo San Pio, -55.05°, -66.616667°, 30–35 m (gear: dredge); Bahia Slogget, -55°, -66.35°, 15–27 m (gear: dredge) ( Chiesa et al. 2005); Bahia Edwards, -45.91555°, -73.661367°, Isla Allen, -44.034867°, -74.1894°, 3–5 m; wood, stones (this study).

Depth range

0– 151 m.

Type locality

East Falkland Island, Discovery 1925–27, stn 53, Port Stanley, 0–2 m (bottom/habitat: kelp roots).

Type specimen location

The Natural History Museum, London.

Remarks

Haplocheira barbimana ( Thomson, 1879) and Haplocheira robusta K.H. Barnard, 1932 are today classified as the subspecies H. barbimana barbimana and H. barbimana robusta ( Moore & Myers 1983) . Haplocheira barbimana barbimana occurs around New Zealand and Auckland Island, whereas H. barbimana robusta is distributed in waters of Chile, Cape Horn and the Falkland Islands ( Moore & Myers 1983). There are slight differences between the subspecies, e.g., the body length range of H. barbimana robusta seems to be slightly greater. There is some degree of variability of characters (e.g., details of head, bases of pereopods 5–7, epimeral plates) and part of it seems to be dependent on the life history stage and their length.

The specimen studied herein agrees mostly with the few published descriptions, except for the following: (1) the shape of the telson: in K.H. Barnard’s (1932) original description the telson is subrectangular, with tapering distal third, small laterally curved processes or spines on a truncate distal margin (vs evenly rounded distally); (2) the ischium of pereopod 5 seems shorter in Barnard’s illustration; (3) the rami of the pleopod illustrated by K.H. Barnard are equal in length (vs clearly shortened outer ramus).

Figures

Fig. 7. Haplocheira barbimana robusta K.H. Barnard, 1932, ♂, 4.2 mm (ZMB 34098). a. Habitus, left body side. b. Mandible. c. Antenna 1.d. Antenna 2. e. Palp of mandible. f. Epimeral plates 1–3. g. Lower lip. Scale bars: a = 500 µm; b–g = 100 µm.

Fig. 8. Haplocheira barbimana robusta K.H. Barnard, 1932, ♂, 4.2 mm (ZMB 34098). a. Maxilla 1. b. Inner plate of maxilliped. c. Outer plate of maxilliped. d. Palp of maxilliped. Scale bars = 100 µm.

Fig. 9. Haplocheira barbimana robusta K.H. Barnard, 1932, ♂, 4.2 mm (ZMB 34098). a. Gnathopod 1. b. Gnathopod 2. Scale bars: a = 100 µm; b = 200 µm.

Fig. 10. Haplocheira barbimana robusta K.H. Barnard, 1932, ♂, 4.2 mm (ZMB 34098). a. Pereopod 3. b. Pereopod 5. c. Pereopod 4. d. Maxilla 2. e. Telson and uropod 3. Scale bars = 100 µm.

Fig. 11. Haplocheira barbimana robusta K.H. Barnard, 1932, ♂, 4.2 mm (ZMB 34098). a. Pereopod 6. b. Pereopod 7. c. Uropod 1. d. Pleopod 1. e. Uropod 2. f. Uropod 3. Scale bars: a, c–f = 100 µm; b = 200 µm.