Kapalana michaelmas, 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 : 407-410

Kapalana michaelmas sp. nov.

Figs 12–15

Holotype, male, 10.3 mm, AM P.75528, off south-east corner of Michaelmas Island , King George Sound, Western Australia, Australia (35°3'S 118°E), sand, 27 m, J. K. Lowry, 17 December 1983, WA 187 . Paratypes: 1 female, 10.0 mm, AM P.75529; 1 male, 5.7 mm, AM P.75530; 1 male, 5.4 mm, AM P.75531; 1 male, 6.5 mm, AM P.75532; 1 male, 7.5 mm, AM P.75533; 1 male, 8.9 mm, AM P.75534; many specimens, AM P.75535; 1 specimen, AM P.75538; collection data same as holotype .

Additional material examined. One female, AM P.75536, near Mistaken Island, Vancouver Peninsula , King George Sound , Western Australia (35°4'S 117°56'E), seagrass, 6 m, R. T. Springthorpe, 13 December 1983 , WA 121; 2 females, AM P.75537, near Mistaken Island, Vancouver Peninsular, King George Sound , Western Australia (25°4'S 117°56'E), seagrass, 3 m, J. K. Lowry, 13 December 1983 , WA 112; 1 male, 6.2 mm, 1 female, 8.3 mm, 1 male, 20 females, SAM C1755 , 6 miles off Semaphore , South Australia (34.837°S 138.484°E), 5 fathoms, H.M. Hale, 12 December 1925 ; 2 females, SAM C6341 , 2 nautical miles south west of Point Avoid, Price Island, Eyre Peninsula , South Australia (35°42'S 135°19'E), shale gutters and algae, 17 m, L. Hobbs on MRV Ngerin, 28 September 1989 ; females & juveniles, SAM C6342 , West Island , South Australia (35°37'S 138°35'E), 5 m, S. A. Shepherd, 20 June 1989 ; many specimens, AM P.99047, Cape Donington, Spencer Gulf , South Australia, (34° 44'S 135°59'E), rough bottom, 15 m, N. Coleman, 21 December 1970 ; 1 male, 1 female, 1 juvenile, AM P.99048, reef front, south of Tantabiddy, Ningaloo Reef , Western Australia, (21°54'36"S 113°55'42"E), coral heads, 9 m, N. L. Bruce and M. Blazewicz-Paszkowycz, 12 June 2008 , NIN 10c.

Type locality. Off south-east corner of Michaelmas Island, King George Sound, Western Australia, Australia (35°3'S 118°E) .

Etymology. Named for Michaelmas Island, the type locality. Used as a noun in apposition.

Description. Based on Holotype, male, 10.3 mm, AM P.75528.

Head. Rostrum long, length 0.5 × head, forming a basal shoulder, apically acute; lateral cephalic lobe with ventral corner subacute, subocular margin deeply recessed, reaching beyond eye, anteroventral corner rounded, ventral margin sloping, posterior margin sloping. Antenna 1 long, length 0.5 × body length; peduncle with scales; peduncular article 1 subequal in length to peduncular article 3, length 1.1 × peduncular article 3, with well-developed subquadrate projection along posterior margin; peduncular article 2 with distal projection; article 2 anterodistal corner without distal projection; flagellum 9-articulate; article 1 short. Antenna 2 length 0.9 × antenna 1; flagellum 10-articulate.

Epistome and upper lip fused, produced, broad base, apically acute. Mandible palp article 2 long and slender (more than 2.5 × as long as broad); palp article 3 slender, blade-like.

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

Gnathopod 1 subchelate; coxa not fused to pereonite 1, length 1.2 × depth, without anteroventral lobe; basis length 2.3 × depth; carpus broad, length 1.5 × depth with setose posterior lobe, propodus palm acute, robust setae absent. Gnathopod 2 carpochelate; coxa not fused to pereonite 2, length 1.6 × depth, without anteroventral lobe or cusp; basis short, broad, length 1.8 × breadth; carpus long, length 1.3 × breadth, broad, palm shallowly excavate, anterodistal tooth large, located near articulation with propodus, posterodistal tooth well defined, medium length, length 0.9 × width; propodus slender, curved, length 4.8 × width, without tooth on posterior margin, posterodistal corner smooth, without spines; dactylus length 0.5 × propodus.

Pereopod 3 coxa not fused to pereonite 3, without anteroventral lobe, length 2.3 × depth; basis, length 2.1 × breadth, with proximal, subquadrate anterodorsal corner, with plumose setal group and simple setae along anterior margin, without denticles along anterior margin; ischium long, length 2.3 × breadth; merus length equal to breadth, short; without ridges. Pereopod 4 coxa not fused to pereonite 4, length 2 × depth, with anterior lobe separated from an anteroventral lobe; basis length 1.7 × breadth, with simple setae along entire anterior margin; ischium long, length 2.9 × breadth; merus very long, length 1.5 × breadth. Pereopod 5 coxa, length 1.3 × depth, without patches of small setae, with setae along ventral margin few or absent; merus with anterior lobe not extending beyond anterior margin of carpus, posterior lobe with 2 plumose setae; propodus with 4 setae along posterior margin; dactylus short, uncinate with 2 accessory hooks. Pereopod 6 coxa with setal fringe ventrally, without patches of small setae near margins; basis with patch of small setae near anterior margin; merus length 2 × breadth; dactylus short, uncinate, with 2 accessory hooks. Pereopod 7 coxa without posterodorsal lobe, without patch of small setae; merus length 2.4 × breadth; dactylus short, uncinate, with 2 accessory hooks.

Pleon. Pleopods 1–3 biramous, decreasing in size anteroposteriorly. Pleopod 1 inner ramus 9-articulate; outer ramus 6-articulate, article 1 evenly swollen. Pleopod 2 inner ramus reduced, 1-articulate; outer ramus, broad, 3-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, with 6 medial setae and 18 lateral setae, with large apical robust seta and smaller slender setae; inner ramus, length 0.6 × outer ramus, with 6 medial, and 4 lateral setae, without large apical robust seta. Uropod 2 uniramous, peduncle, length 2.9 × breadth, 3.7 × length of ramus; ramus small with 7 denticles and 1 slender apical seta. Uropod 3 uniramous, peduncle length 1.9 × breadth; ramus with 2 curved hooks. Telson length 0.6 × breadth, moderately cleft (21 %), each lobe with 38–39 anteriorly directed hooks in 2 rows.

Female (sexually dimorphic characters). Based on female, 10.0 mm, AM P.75529. Antenna 1 flagellum 10-articulate. Antenna 2 flagellum 7-articulate. Pereonite 1 without lateral keel. Gnathopod 1 coxa, length 1.4 × depth; basis, length 2.6 × depth, carpus length 0.7 × depth with setose posterior lobe. Gnathopod 2 simple; basis, broad, length 1.9 × breadth, carpus length 1.7 × breadth. Pereopod 5 coxa, length 1.4 × depth. Oostegites from gnathopod 2 to pereopod 5.

Tube. Tubes of adult males encrusted with fine and coarse organic matter. Tubes of adult females in two parts, the

; paratype, female, 10.0 mm, AM P.75529; Michaelmas Island , King George Sound , Western Australia, Australia. Pleopods 1 – 3 insertion points of setae are indicated by small circles. Scales represent 0.1 mm

anterior end encrusted with fine and coarse organic matter, the posterior end encrusted with large sand grains. Tubes of juveniles attached in a ring, circling the tube of adult female.

Habitat. Sublittoral (3–27 m depth).

Remarks. The shape of gnathopod 2 propodus and carpus changes as males grow, with the propodus becoming curved and slender in large males. In males less than 6 mm in length, gnathopod 2 is subchelate with a small anterodistal and posterodistal tooth. In males longer than 6 mm, gnathopod 2 becomes carpochelate, and the carpus develops an excavate posterior margin.

Kapalana michaelmas shares with K. durraween , K. maia and K. wadei a lack of apical robust seta on the inner ramus of uropod 1. The rostrum has a basal shoulder (a character shared with K. kimbla and K. wadei ) but the rostrum is not as long as K. wadei (the rostrum is very long in K. wadei ). Gnathopod 1 coxa is not fused to pereonite 1 in K. michaelmas (fused in K. wadei ). In K. michaelmas the posterior lobe of the carpus of pereopod 5 bears 2 plumose setae and K. wadei bears 6 plumose setae.

Distribution. Australia. Western Australia: King George Sound; Ningaloo Reef. South Australia: off Semaphore; Price Island, Eyre Peninsula; West Island; Cape Donington, Spencer Gulf.

10.0 mm, AM P.75529; Michaelmas Island , King George Sound, Western Australia, Australia .

Scales represent 0.1 mm

Figures

Figure 12. Kapalana michaelmas sp. nov., tubes of female and juveniles; left,AM P.100314, 6 miles off Semaphore, SouthAustralia,Australia (length of central tube = 30 mm); right, AM P.75535, Michaelmas Island, King George Sound, Western Australia, Australia (length of tube = 70 mm).

Figure 13. Kapalana michaelmas sp. nov., holotype, male, 10.3 mm, AM P.75528

Figure 14. Kapalana michaelmassp.nov., holotype, male, 10.3 mm,AM P.75528; paratype, female,

Figure 15. Kapalana michaelmassp.nov., holotype, male “e”, 10.3 mm,AM P.75528, Paratype, male “a”, 5.7 mm,AM P.75530; paratype, male “b”, 6.5 mm,AM P.75532; paratype, male “c”, 7.5 mm, AM P.75533; paratype, male “d”, 8.9 mm,AM P.75534; Michaelmas Island, King George Sound, Western Australia, Australia. Gnathopod 2 males “a”, “b”, “c”, “d” insertion points of setae are indicated by small circles. Scale represents 0.1 mm.