Chevalia burrewarra, Springthorpe & Hughes, 2024

Springthorpe, Roger T. & Hughes, Lauren E., 2024, Re-description of Chevalia aviculae Walker, 1904, five new species and new records of Chevaliidae from Australia and New Zealand (Crustacea: Peracarida: Amphipoda: Senticaudata), Records of the Australian Museum 76 (3), pp. 157-194 : 173-177

Chevalia burrewarra sp. nov.

urn:lsid:zoobank.org:act:4D6C5B67-572D-4B9F-A748-3241478EC9DE

( Figs 1–2 , 14–16 )

Holotype: Male, 4.4 mm, dissected (carcass and 2 slides), AM P.100382, East Wall, north of Burrewarra Point, New South Wales, 35°50.024'S 150°14.161'E, from macroalga Curdiea crassa Millar, 1990 , with small amount of Martensia australis Harvey, 1855 , by hand on SCUBA, 25m, coll. G. Wilson, A. Millar and N. Yee, 25 October 2002, station NSW 1986. Paratypes: female, ovigerous, 5.6 mm, dissected (carcass and 1 slide), AM P.100383; 3 ovigerous females, 4 females with oostegites, 4 immature specimens, AM P.100384, same location as holotype; 1 male specimen, AM P.100385, East Wall, north of Burrewarra Point, New South Wales, 35°50.024'S 150°14.161'E, from macroalga Peyssonelia nova-hollandiae Kützing, 1847 , by hand on SCUBA, 25 m, coll. G. Wilson, A. Millar and N. Yee, 25 October 2002, station NSW 1985; 8 females, 12 male specimens, AM P.100386, gutters, north of Burrewarra Point, New South Wales, 35°49.822'S 150°14.083'E, from macroalga Stypopodium flabelliforme Weber-van Bosse, 1913, by hand on SCUBA, 24 m, coll. G. Wilson, A. Millar and N. Yee, 27 October 2002, station NSW 1992; 1 specimen, AM P.100387, gutters, north of Burrewarra Point, New South Wales, 35°49.865'S 150°14.083'E, from macroalga Martensia australis Harvey, 1855 , by hand on SCUBA, 23 m, coll. G. Wilson, A. Millar and N. Yee, 27 October 2002, station NSW 1999; 1 male (carcass and 2 slides), 1 female (carcass and 1 slide), AM P. 100388, gutters north of Burrewarra Point, New South Wales, 35°49.822'S 150°14.083'E, from macroalga Pachymenia prostrata Agardh, 1890 , by hand on SCUBA, 24 m, coll. G. Wilson, A. Millar, N. Yee, 27 October 2002, station NSW 1993.

Additional material examined. New South Wales. 12 specimens, AM P.100389, same locality as holotype ; 1 male specimen, AM P.72655, north of Burrewarra Point , 35°49.867'S 150°14.083'E, gutters, macroalga Codium lucasii Setchell in Lucas, 1935, by hand on SCUBA, 23 m, coll. G. Wilson, A. Millar and N. Yee, 27 October 2002, station NSW 1997 ; 1 male specimen, AM P.23986, east of Long Reef , 33°44'S 151°19'E, 24 m, Australian Museum Shelf Benthic Survey, 27 April 1972 ; 7 specimens, AM P. 56703, 100 m north west of Split Solitary Island , 30°14.0'S 153°10.8'E, plate coral, solitary ascidian, gorgonian and sponges, 17 m, coll. G.D.F. Wilson, 7 March 1992, station NSW 687 .

Victoria. 14 specimens, AM P.30186, Crib Point, Western Port , 38°22'S 145°14'E, sponge on reef, 13 m, Fisheries & Wildlife Division , Victoria, February 1973 , station CPBS 33 S ; 2 immature specimens, NMV J51338 , central Bass Strait , 38°30.198'S 144°15.0'E, 40 m, Smith-McIntyre grab, 13 May 1998 , station VC 18 C3; 4 males, 5 females, 3 immature specimens, NMV J28715 , eastern Bass Strait, 12.4 km west-south-west of Point Ricardo , 37°51.11'S 148°29.93'E, 32 m, sand-shell, Smith-McIntyre grab, 20 September 1990 .

Type locality. East Wall, north of Burrewarra Point , New South Wales, 35°50.024'S 150°14.161'E .

Etymology. Named from the type locality as a noun in apposition.

Diagnosis.Antenna 1 length 0.3 times body length, accessory flagellum 2-articulate. Gnathopod 1 coxa anterodistal corner produced. Gnathopod 2 carpus subequal to propodus, propodus palm near transverse, without posterodistal shelf, defined by distal dactylar socket and subacute tooth. Pereopod 7 basis rectilinear, posterodistal corner subquadrate or rounded, not produced; carpus posterodistal corner with 1 submarginal robust seta. Uropod 2 outer ramus dorsal margin with 2 apical robust setae. Uropod 3 rami subequal in length to peduncle. Telson apical margin convex.

Description. Based on holotype male, 4.4 mm, AM P.100382.

Head. Eyes of small size, partially situated in lateral lobe of the head, lateral cephalic lobe rounded. Antennae densely setose. Antenna 1 length 0.3 times body length; peduncular article 1 longer than article 3; primary flagellum with 7 articles; accessory flagellum 2-articulate, article 2 rudimentary. Antenna 2 slightly shorter than antenna 1; article 4 length 1.2 times article 5; article 5 length 0.7 times flagellum; flagellum with 7 articles. Mandible palp, article 1 length 0.3 times article 2, article 2 length 1.1 times article 3; incisor with 4 teeth, lacinia mobilis with 3 teeth, accessory setal row with 5 setae, molar triturative. Lower lip, inner lobes and outer lobes separated, inner lobes large and fleshy. Maxilla 1 inner plate without setae; outer plate with 10 robust setae; palp 2-articulated with 4 apical robust setae and 2 subapical setae. Maxilla 2 unknown. Maxilliped inner plate subrectangular, apical margin with 3 robust setae and several plumose setae, medial margin without plumose setae; outer plate shorter than palp article 2, with 3 robust setae and row of plumose setae on medial and facial margins, with 2 apical plumose setae; palp, article 2 longer than articles 3 and 4 combined, article 4 with 1 long distal seta.

Pereon. Gnathopod 1 coxa subequal to coxa 2, with anterodistal corner not produced, rounded to subquadrate; basis anterior margin concave, posterior margin convex, margins with few setae; carpus length 3.7 times breadth, 1.3 times propodus length, posterior margin lined with setae; propodus length 2.5 times breadth, margins lined with setae, palm acute, not defined by corner or robust setae; dactylus distally expanded, blunt. Gnathopod 2 basis anterior margin straight and posterior margins weakly convex, with few slender setae; carpus length 1.9 times breadth, subequal to propodus; propodus subchelate, massive, posterior margin parallel to anterior margin, palm near transverse, without posterodistal shelf, defined by distal dactylar socket and subacute tooth; dactylus not reaching palm corner. Pereopod 3 (based on female) basis subovate, length 2.6 times breadth; merus subovate; carpus length 1.4 times breadth; propodus length 2.4 times breadth. Pereopod 4 (based on female) basis rectilinear, length 4.1 times breadth; merus subovate; carpus length 1.2 times breadth; propodus length 2.4 times breadth. Pereopods 5–7 merus distal corners weakly produced; dactylus anterior margin with accessory spine. Pereopod 5 basis proximally narrow distally broad; merus length 1.3 times breadth; carpus length 1.3 times breadth, posterodistal corner with 1 submarginal robust seta; propodus length 3.3 times breadth. Pereopods 6 –7 merus distal margins with one long slender plumose seta. Pereopod 6 basis proximally narrow distally broad, length 1.8 times breadth; merus length 1.7 times breadth; carpus length twice breadth, posterodistal corner with 1 submarginal robust seta; propodus length 5 times breadth. Pereopod 7 basis rectilinear, length twice breadth, posterodistal projection present; merus length 1.8 times breadth; carpus length 1.8 times breadth, posterodistal corner with 1 submarginal robust seta; propodus length 4.2 times breadth.

Pleon. Epimeron 3 posterodistal corner broadly rounded, without notch. Urosomites 1–2 fused. Uropod 1 peduncle length 2.8 times breadth, 1.3 times outer ramus, dorsal margin with plumose setae; rami outer margins minutely pectinate apically, inner margins lined with setae; inner ramus length 6 times breadth, 1.3 times outer ramus, without apical robust setae; outer ramus outer margin with 2 slender setae, with 2 apical robust setae. Uropod 2 peduncle length 1.4 times outer ramus, with 3 long plumose setae; inner ramus length 7.5 times breadth, 1.5 times outer ramus, without robust setae; outer ramus dorsal margin, apical margin cuticle with 3 teeth and with 2 apical robust setae. Uropod 3 peduncle length 1.1 times breadth, 1.4 times length inner ramus; inner ramus 1.4 times longer than outer ramus, with long apical plumose setae, without robust seta; outer ramus with long apical plumose setae and 1 apical robust seta. Telson with pair of denticular patches; apical margin convex with 2–3 pairs of plumose setae.

Female (Sexually dimorphic characters). Based on paratype female, 5.6 mm, AM P.100383. Pereopods 3–5 oostegites present. Gnathopod 1 dactylus recurved. Pereopod 7 basis posterodistal corner without projection.

Remarks. The combination of the simple palm with broad dactylus in gnathopod 1 and the transverse palm of gnathopod 2 separate Chevalia burrewarra sp. nov. from the other Chevalia . The gnathopod 1 of Chevalia burrewarra sp. nov. is distally broad giving a falcate appearance while other species the dactylus is more typically recurved and narrowing distally. Chevalia burrewarra sp. nov. has an extremely long basis on pereopod 4. the length being more than 4 times breadth (other species are about twice). Only Chevalia burrewarra sp. nov., C. freycinet sp. nov. and C. tenuis have a simple gnathopod 1 separating them from other Indo-Pacific Chevalia species. In C. burrewarra sp. nov., C. sprightly sp. nov. and C. bardi sp. nov. the gnathopod 1 basis is convex along both margins while only convex or weakly so in C. csiro and C. freycinet sp. nov.

Distribution. Australia. New South Wales: Burrewarra Point, Long Reef and Split Solitary Island (current study). Victoria: Western Port and Bass Strait (current study).

Figures

Figure 1. Distribution map of Australian and New Zealand Chevaliidae species. Stars represent type localities; circles represent additional data points.

Figure 2. Field guide to Australian and New Zealand Chevaliidae species.

Figure 14. Chevalia burrewarra sp. nov., male, holotype, 4.4 mm, AM P.100382, Burrewarra Point, New South Wales. Scale lines represent 0.1 mm.

Figure 15. Chevalia burrewarra sp. nov., male, holotype, 4.4 mm,AM P.100382, Burrewarra Point, New South Wales; ovigerous female, paratype, 5.6 mm, AM P.100383, Burrewarra Point, New South Wales. Scale lines represent 0.2 mm.

Figure 16. Chevalia burrewarra sp. nov., male, holotype, 4.4 mm,AM P.100382, Burrewarra Point, New South Wales; ovigerous female, paratype, 5.6 mm, AM P.100383, Burrewarra Point, New South Wales. Scale lines represent 0.2 mm.