Melita festiva ( Chilton, 1885 )

Springthorpe, Roger T., 2023, Melita lowryi, a New Species of Melitidae (Crustacea: Amphipoda: Senticaudata) from New Zealand, and the Redescription of Melita festiva (Chilton, 1885) from Australia, Records of the Australian Museum (Rec. Aust. Mus.) 75 (4), pp. 547-558 : 548-553

Melita festiva ( Chilton, 1885)

Figs 1–4

Maera festiva Chilton, 1885: 1037 , pl. 46, fig. 2a–c.— Stebbing, 1910: 642.

Maera rubromaculata Haswell, 1885: 105 (in part).

Ceradocus rubromaculata Della Valle, 1893: 720 (in part).— Stebbing, 1906: 431, 732 (in part).

Melita festiva .— Sheard, 1937: 24 (list).—J. L. Barnard, 1972: 117 (in part = M. lowryi sp. nov.).— Barnard & Barnard, 1983: 665.— Zeidler, 1989: 335.— Lowry & Springthorpe, 2005: 238, tab. 1.

Abludomelita festiva .— Karaman, 1981: 40.

Ledoyeromelita festiva . — Labay, 2016: 65.

Not Melita festiva .— Chilton, 1916: 359, figs 1–2.— Hurley, 1957: 6.— Fenwick, 1976: 2. (= M. lowryi sp. nov.).

Syntypes: 2 specimens (2 micro slides), CMNZ, Sydney Harbour , New South Wales, Australia (catalogued but currently missing, Shaw & Poore, 2016: 32) ; 1 male, 1 female (wet specimens in alcohol), CMNZ 2015.149.154–155, Sydney Harbour , New South Wales, Australia, 1 January 1884 (labelled as “cotypes”) .

Additional material examined. New South Wales: 1 male, 10.4 mm (dissected, carcass, and 4 micro slides), AM P.18120, Bottle and Glass Rocks, Port Jackson , ca. 33°50.9'S 151°16.2'E, between tide marks, 28 July 1923, coll. A. A. Livingstone ; 1 male (9.7 mm), 1 ovigerous female (6.7 mm), 3 females (5.8–8.5 mm), AM P.5333, Coogee , 33°55'S 151°16'E, coll. F. A. McNeill ; 4 males (3.3–8.3 mm), 1 ovigerous female (6.7 mm), 5 females (3.3–8.5 mm), AM P.36647, Murrumbulga Point, Twofold Bay , 37°04.7'S 149°53.1'E, gravel and algae, S. J. Keable & J. T. van der Velde, 9 October 1984, station Q11 ; 1 male (8.3 mm; carcass and 3 micro slides), AM P.55021, Murrumbulga Point, Twofold Bay , 37°04.7'S 149°53.1'E, gravel and algae, S. J. Keable & J. T. van der Velde, 9 October 1984, station Q11 ; 1 ovigerous female (6.7 mm; dissected, carcass, and 2 micro slides), AM P.55022, Murrumbulga Point, Twofold Bay , 37°04.7'S 149°53.1'E, gravel and algae, 9 October 1984, coll. S. J. Keable & J. T. van der Velde , station Q11 ; 1 male (5.4 mm), 1 female (5.8 mm), AM P.55118, Murrumbulga Point, Twofold Bay , 37°04.7'S 149°53.1'E, subtidal rock platform, 2–9 m, S. J. Keable & E. A. Bamber, 11 December 1984, station Q2 ; 2 males (4.2–5.4 mm), AM P.55119, Murrumbulga Point, Twofold Bay , 37°04.7'S 149°53.1'E, kelp holdfast, subtidal rock platform, 3 m, S. J. Keable & E.A. Bamber, 11 December 1984, station Q2 ; 1 female (6.7 mm), AM P.55120, Murrumbulga Point, Twofold Bay , 37°04.7'S 149°53.1'E, subtidal rock platform, P.A. Hutchings, 9 October 1984, station Q5 ; 1 male (4.2 mm), 2 females (7.5–7.9 mm), AM P.106019, Murrumbulga Point, Twofold Bay , 37°04.7'S 149°53.1'E, P.A. Hutchings & S. J. Keable, 17 September 1985, station Q7 ; 1 female (4.2 mm), AM P.106020, Twofold Bay, Murrumbulga Point , 37°04.7'S 149°53.1'E, S. J. Keable & E. A. Bamber, 11 December 1984, station Q18 .

Australian Commonwealth Territory: 1 specimen (5.4 mm), AM P.92920, Murrays Beach , Jervis Bay, 35°07.5'S 150°45.5'E, hand collected, spongeencrusted dead barnacles 0.5 m, 28 June 1981, H. E. Stoddart, station MI NSW 52 .

Victoria. 2 males, 6 females, NMV J13115 , off Crib Point, Western Port , 38°20.56'S 145°15.06'E, Smith-McIntyre grab, 2 m, coll. A. J. Gilmour, 5 April 1965, station CPBS-N 03 ; 1 male, NMV J13116 , off Crib Point, Western Port , 38°20.83'S 145°13.5'E, Smith-McIntyre grab, 13 m, coll. A. J. Gilmour, 23 March 1965, station CPBS-N 32 ; 1 female, NMV J13117 , off Crib Point, Western Port , 38°20.56'S 145°15.06'E, Smith-McIntyre grab, 2 m, coll. A. J. Gilmour, 5 April 1965, station CPBS-N 03 ; 1 male, 1 female, NMV J13118 , off Crib Point, Western Port , 38°21'S 145°13.8'E, Smith-McIntyre grab, 11 m, coll. A. J. Gilmour, 12 October 1964, station CPBS-B 4 ; 1 male (7.9 mm), 1 ovigerous female (6.3 mm), AM P.106018, Hayley Point, Mounts Bay , 38°47'S 143°40'E, under stones, rocky shore low tide, R. T. Springthorpe & P. B. Berents, 4 May 1988, station MI VIC-69 .

Type locality. Sydney Harbour , New South Wales, Australia, ca. 33°51.55'S 151°13.35'E .

Description. Male (based on male, 10.4 mm, AM P.18120).

Head. Anteroventral margin with large notch on anteroventral corner, anteroventral corner rounded; eyes present, well developed. Antenna 1 longer than antenna 2, peduncular article 1 shorter than 2 with 3 robust setae along posterior margin, article 2 longer than article 3; accessory flagellum 6- or 7-articulate; flagellum 31+ articulate.Antenna 2 peduncular article 4 subequal to article 5; flagellum strongly setose, 13-articulate. Mandible molar large, setal row well developed; palp well-developed, 3-articulate; article 1 not produced distally, length 0.5 times article 2, article 2 length 0.8 times article 3 with several marginal setae, article 3 rectilinear with a bunch of apical setae and several marginal setae. Maxilla 1 inner plate long, subrectangular, with 8 apical plumose setae, outer plate with 9 apical setal teeth, palp 2-articulate, slightly curved with numerous apical and subapical setae. Maxilla 2 inner plate without oblique setal row on inner face, with marginal setal row. Maxilliped plates strong, palp article 2 rectilinear, dactyl curved.

Pereon. Coxae 1–3 without posteroventral cusp. Gnathopod 1 not sexually dimorphic, subchelate; coxa anteroventral corner produced, rounded, anterior margin slightly concave; carpus about 2 times longer than broad, length 1.2 times propodus; propodus small, linear, without hump along anterior margin, without anterodistal projection or hood, posterodistal margin not swollen, palm acute and convex, entire, without anterodistal projection near base of dactylus; dactylus articulating distinctly with propodus, well developed, fitting palm, posterior margin not swollen at base. Gnathopod 2 significantly enlarged in male, sexually dimorphic; left and right gnathopods subequal in size, subchelate; merus with sharply produced posterodistal process; carpus compressed, length about 0.5 times breadth, posterior margin lobate; propodus expanded, with numerous rows of dense setae medially and along anterior and posterior margins, palm acute, with a row of robust setae along lateral margin, with large truncate mid palmar tooth, posterodistal corner defined by large tooth and 2 robust setae medially and laterally; dactylus apically truncate, hammer-like, closing along palm. Pereopod 4 smaller than pereopod 3, coxa with posteroventral lobe. Pereopods 5–7 similar in shape; merus, carpus, and propodus with numerous dense bunches of long slender setae along anterior and posterior margins. Pereopod 5 smaller than pereopods 6–7; basis expanded, posterior margin almost straight, minutely serrate, posteroventral corner broadly rounded; dactylar unguis bifid. Pereopod 6 coxa sexually dimorphic, anterior lobe slightly produced, rounded. Pereopod 7 subequal in size to pereopod 6.

Pleon. Pleonites 1–3 without dorsal teeth, spines or setae. Epimeron 1 posteroventral corner subquadrate. Epimeron 2 posteroventral corner subquadrate. Epimeron 3 posterior margin smooth, ventral margin serrate along posterior quarter, posteroventral corner with strongly produced acute tooth. Urosomite 1 without dorsal mid-line spine. Urosomite 2 with 4 dorsal spines with 2 dorsal robust setae in 2 groups. Uropod 1 peduncle with basofacial robust seta. Uropod 3 inner ramus scale-like, much shorter than outer ramus; outer ramus length 4.5 times breadth, 2-articulate, article 2 short. Telson deeply cleft, as long as broad, lobes apically acute with 2 subapical robust setae on each lobe, inner and outer margins lacking setae.

Female (Sexually dimorphic characters). Based on female, 6.7 mm, AM P.55022. Oostegites linear, sparsely setose, present on gnathopod 2 and pereopods 3–5. Gnathopod 2 carpus short, length 1.4 times breadth, posterior margin not lobate; propodus subovate, length 1.2 times carpus, palm acute, corner defined by subquadrate tooth and 2 robust setae; dactylus apically acute, closing along palm. Pereopod 6 coxa anterior lobe slightly produced, bilobate.

Habitat. Marine, rocky intertidal to 11 m depth.

Remarks. Melita festiva ( Chilton, 1885) is distinguished from almost all other species of Melita by the distinctive second gnathopod in the male having an inflated sub-ovoid propodus and heavy, hammer-like, distally truncate dactyl. Melita festiva ( Chilton, 1885) and Melita lowryi sp. nov. appear superficially similar in the form of male gnathopod 2. Melita festiva differs from Melita lowryi sp. nov., in the heavily setose gnathopod 2 and pereopods 5 to 7, gnathopod 2 propodus palm having a single subquadrate tooth (2 teeth in M. lowryi ), urosomite 1 lacking dorsal mid-line spine (with dorsal mid-line spine in M. lowryi ), uropod 3 outer ramus shorter than in M. lowryi and telson without medial setae (1 seta per lobe in M. lowryi ).

Distribution. Australia. New South Wales: Port Jackson ( Chilton, 1885, current study); Twofold Bay (current study). Australian Commonwealth Territory: Jervis Bay (current study). Victoria: Western Port; Mounts Bay (current study).

Figures

Figure 1. Melita festiva (Chilton, 1885), male, 10.4 mm, AM P.18210, Bottle & Glass Rocks, Port Jackson, New South Wales, Australia.

Figure 2. Melita festiva (Chilton, 1885), male, 10.4 mm, AM P.18210, Bottle & Glass Rocks, Port Jackson, New South Wales,Australia, female, 6.7 mm, AM P.55022, Murrumbulga Point, Twofold Bay, New South Wales, Australia. Scales for A1–2 represent 0.5 mm, remainder represent 0.2 mm.

Figure 3. Melita festiva (Chilton, 1885), male, 10.4 mm, AM P.18210, Bottle & Glass Rocks, Port Jackson, New South Wales, Australia, female, 6.7 mm, AM P.55022 Murrumbulga Point, Twofold Bay, New South Wales, Australia. Scales represent 0.5 mm.

Figure 4. Melita festiva (Chilton, 1885), male, AM P.18210, Bottle & Glass Rocks, Port Jackson, New South Wales, Australia, female, 6.7 mm, AM P.55022, Murrumbulga Point, Twofold Bay, New South Wales, Australia. Scales for P5–7 represent 0.5 mm, remainder represent 0.2 mm.