Kapalana stebbingi, Berents & Lowry, 2018

Berents, Penelope B. & Lowry, J. K., 2018, The New Crustacean Amphipod Genus Kapalana from Australian Waters (Senticaudata, Ischyroceridae, Ischyrocerinae, Cerapodini), Records of the Australian Museum 70 (4), pp. 391-421 : 410-413

Kapalana stebbingi sp. nov.

Figs 16–19

Cerapus abditus .— Stebbing, 1910: 616, pl. 5a.

Holotype, male, 8.9 mm, AM P.51210, east of Port Jackson , New South Wales, Australia (33°52'S 151°23'E), mud, 80 m, FRV Kapala , 27 October 1980, stn K-80-20-11 . Paratypes: 1 female, ovigerous, 6.4 mm, AM P.51211; 1 male, 6.5 mm, AM P.99058; 1 male, 5.7 mm, AM P.99059; 1 male, 4.9 mm, AM P.99060; many specimens, AM P.99061; all same data as holotype. Many specimens, AM P.99062, south-east of Broken Bay , New South Wales, Australia, (33°36'S 151°30'E), trawl, 71–75 m, FRV Kapala , 10 February 1986, K86-01-02 ; 1 male, 1 female, MV J17211 , south of Point Hicks , Victoria, Australia (38°14'48"S 149°09'18"E), WHOI epibenthic sled, 200 m, M.F. Gomon, 24 July 1986, Slope 41.

Additional material. Many specimens, AM P.99063, southeast of Broken Bay , New South Wales, Australia, (33°36'S 151°30'E), trawl, 71–75 m, FRV Kapala , 10 February 1986 ; 1 female, AM P.2526; 1 male, 1 female, AM P.2527; 3–4 km off BotanY BaY, New South Wales, Australia, (34°05'S 151°15'E), mud, 91–95 m, E. R. Waite on HMCS Thetis, 11 March 1898 , stn 37. 1 male, AM P.2528, 9– 12 km off Cape Three Points , New South Wales, Australia, (33°32'S 151°32'30"E), trawl, sticky mud and shell, 75–91 m, E. R. Waite on HMCS Thetis, 25 February 1898 , stn 13; 1 male, AM P.99064, east of Broken Bay , New South Wales, Australia, (33°35'S 151°41'E), 135 m, FRV Kapala , 10 February 1986 , K86-01-03; 2 specimens, AM P.99065, east of Long Reef Point , New South Wales, Australia, (33°46'S 151°43'E), dredge, 176 m, FRV Kapala , 5 December 1977 , K77-23-01.

Type locality. East of Port Jackson , New South Wales, Australia (33°52'S 151°23'E) .

Etymology. Named for T.R.R. Stebbing, who first illustrated this species.

Description. Based on holotype male, 8.9 mm, AM P.51210.

Head. Rostrum long, length 0.3 × head, evenly tapered, apically acute; lateral cephalic lobe with ventral corner rounded, subocular margin deeply recessed, reaching beyond eye, ventral margin sloping, posterior margin sloping. Antenna 1 long, length 0.6 × body length; peduncle with scales; peduncular article 1 shorter than article 3, length 0.6 × peduncular article 3, not produced anterodistally and anteromedially, with strong acute projection along posterior margin, posterodistal corner produced; peduncular article 2 anterodistal corner without distal projection; flagellum 9-articulate; article 1 long. Antenna 2 length 1.1 × antenna 1; flagellum 7-articulate.

Epistome and upper lip fused, produced, broad base, apically acute.

Pereon. Pereonite 1 with lateral keel, without sternal keel. Pereonites 2–3 without sternal keel. Pereonite 5 length 1.8 × depth.

Gnathopod 1 simple; coxa fused to pereonite 1, without anteroventral lobe; basis length 2.2 × depth; carpus very broad, length 2.2 × depth with setose posterior lobe, propodus palm extremely acute. Gnathopod 2 carpochelate; coxa fused to pereonite 2, length 1.3 × depth, without anteroventral lobe or cusp; basis long, slender, length 3 × breadth, basis without anteroproximal group of long slender setae, basis without anteroproximal bulge; carpus very long, length 1.9 × breadth, slender, palm straight, anterodistal tooth small, located near articulation with propodus, posterodistal tooth poorlY defined; propodus slender, slightlY curved, length 5.5 × width, with proximal tooth on posterior margin, posterodistal corner minutely rugose with 1 tooth; dactylus length 0.5 × propodus.

Pereopod 3 coxa not fused to pereonite 3, without anteroventral lobe, length 1.7 × depth; basis, length 2.4 × breadth, with proximal, subquadrate anterodorsal corner, with plumose setal group and simple setae along anterior margin, without denticles along anterior margin; ischium long, length 3.9 × breadth; merus length 1.1 × breadth; short; without ridges. Pereopod 4 coxa not fused to pereonite 4, length 2.3 × depth, with anterior lobe separated from an anteroventral lobe; basis length 1.8 × breadth, with plumose setae along entire anterior margin; ischium long, length 2.5 × breadth. Pereopod 5 coxa, length 1.5 × depth, with patches of small setae, with setae along ventral margin; merus with anterior lobe extending beyond anterior margin of carpus, posterior lobe with 1 simple seta; propodus with 2 setae along posterior margin; dactylus short, uncinate with 1 accessory hook. Pereopod 6 coxa with setal fringe ventrally, with patch of small setae near posterior margin; basis with patch of small setae near anterior margin; merus length 2.2 × breadth; dactylus short, uncinate, with 1 accessory hook. Pereopod 7 coxa with posterodorsal lobe, with patch of small setae; merus length 2.5 × breadth; dactylus short, uncinate, with 1 accessory hook.

Pleon. Pleopods 1–3 biramous, decreasing in size anteroposteriorly. Pleopod 1 inner ramus 7-articulate; outer ramus 4-articulate, article 1 with straight medial margin. Pleopod 2 inner ramus reduced, 1-articulate; outer ramus, broad, 1-articulate. Pleopod 3 inner ramus reduced, 1-articulate; outer ramus broad, 1-articulate. Uropod 1 biramous; peduncle length 1.4 × outer ramus; rami with distoventral fan of robust setae; outer ramus with lateral row of denticles, without medial setae, with 8 lateral setae, with large apical robust seta and smaller slender setae; inner ramus, length 0.6 × outer ramus, without medial setae, with 4 lateral setae. Uropod 2 uniramous, peduncle, length 2.8 × breadth, 4.4 × length of ramus; ramus small with 4 denticles and 1 slender apical seta. Uropod 3 uniramous, peduncle length 1.8 × breadth; ramus with 2 curved hooks. Telson length 0.5 × breadth, moderately cleft (54 %), each lobe with 20–23 anteriorly directed hooks in 2 rows.

Tube. Encrusted with sand grains and pieces of shell. Tubes of juveniles attached in a ring, circling the tube of adult female.

Habitat. Sublittoral and continental shelf (71–200 m depth).

Remarks. The shape of gnathopod 2 basis, propodus and carpus changes as males grow, with the propodus becoming slender and the basis carpus becoming much longer than gnathopod 2 is subchelate. The proximal tooth on posterior margin is not prominent in males smaller than 5 mm. The carpus posterior margin is excavate in males 5.5 to 7 mm.

Kapalana stebbingi is the only species in the species group with antenna 1 peduncular article 1 with a strong subacute projection along the posterior margin, gnathopod 1 simple, the dactylus of pereopods 5–7 bearing 1 accessory hook, gnathopod 2 with a very long and slender carpus, the posterior margin of the propodus bearing a proximal tooth and a straight palm (all other species have an excavate palm).

Distribution. Australia. New South Wales: off Cape Three Points; off Botany Bay ( Stebbing, 1910); east of Port Jackson; east of Long Reef; off Broken BaY. Victoria: south of Point Hicks.

Figures

Figure 16. Kapalana stebbingi sp. nov., paratype, male, 8.0 mm,AM P.99061, east of Port Jackson, New South Wales, Australia.

Figure 17. Kapalana stebbingi sp. nov., left, tube, AM P.2528, 9–12 km off Cape Three Points, New South Wales, Australia, (tube diameter = 1 mm); right, Paratype, male, 8.0 mm, AM P.99061, dorsal view of head and pereonites 1–3, east of Port Jackson, New South Wales, Australia.

Figure 18. Kapalana stebbingi sp. nov., holotype, male, 8.9 mm, AM P.51210; paratype, male “a”, 4.9 mm, AM P.99060; paratype, male “b”, 5.7 mm, AM P.99059; paratype, male “c”, 6.5 mm, AM P.99058; paratype, female, 6.4 mm, AM P.51211; east of Port Jackson, New South Wales, Australia. Gnathopod 2 males “a”, “b”, “c” insertion points of setae are indicated by small circles. Scales represent 0.1 mm.

Figure 19. Kapalana stebbingi sp. nov., holotype, male, 8.9 mm, AM P.51210; paratype, female, 6.4 mm, AM P.51211; east of Port Jackson, New South Wales, Australia. Pleopods 1–3 insertion points of setae are indicated by small circles. Scales represent 0.1 mm.