Maera mooreana Myers, 1989

Appadoo, Chandani, Myers, Alan A. & Fagoonee, Indur, 2002, The genera Quadrimaera and Maera (Amphipoda: Gammaridea: Melitidae) from Mauritius, Journal of Natural History 36 (6), pp. 641-673 : 661-664

Maera mooreana Myers, 1989

(®gures 12, 13)

Maera mooreana Myers, 1989: 72 , ®gures 9, 10.

Maera sp. 1 : Appadoo and Steele, 1998: 639.

Material examined

1, from Ulva reticulata Forskal and Gracilaria millardetii J. Agardh, Souillac (20ss31¾S 57ss30.7¾E), 3 February 1998. 1, from Padina sp. and Halimeda sp. , Grand Baie (20ss0.5¾S 57ss34¾E), 5 May 1999. 1, 1, from mixture of Padina sp. , Gracilaria salicornia , Ulva lactuca and Dictyota divaricata Lamouroux, Choisy (20ss01¾S 57ss32.7¾E), 25 January 2000.

Description

Male. Length, 3.5 mm. Head without subocular notch; eyes subround. Antenna 1 peduncle article 1 with three robust setae on ventral margin; peduncle article 2, 1.8 times article 1; article 3, 0.3 times article 2; primary ¯agellum 13-articulate; accessory ¯agellum ®ve-articulate. Antenna 2 peduncle article 5 shorter than 4; ¯agellum eight-articulate. Mandible palp; article 2 with about eight setae on posterior margin; article 3, 0.9 times article 2, with four terminal setae and three medial setae. Maxilla 1 inner plate with three terminal setae. Maxilla 2 outer plate wider than inner plate. Gnathopod 1 coxa antero-ventrally rounded; basis 3 times as long as broad with four long setae on the posterior margin; carpus 2.2 times as long as broad; propodus 1.8 times as long as broad; palmar margin slightly convex, with short robust setae; dactylus ®tting palm. Gnathopod 2 coxa subquadrate; basis robust and expanded, 1.4 times as long as broad and produced postero-distally into a protuberance; merus postero-ventral margin produced into an acute tooth; carpus subtriangular; propodus subovate, 1.5 times as long as broad; palm slightly oblique with a deep medial excavation and a semi-elliptical excavation at the postero-distal margin forming a short de®ning tooth, palm with a few short robust setae and a few ®ne setae; dactylus posterior margin asetiferous. Pereopod 3±4 coxa 1.3 times as long as broad with ®ne setae on ventral margin; basis 3.5 times as long as broad, anterior and posterior margins with short robust setae; merus slightly expanded antero-distally; dactylus slender, not bi®d. Pereopod 5 basis subrectangulate, 2.4 times as long as broad, anterior and posterior margins bearing short robust setae. Pereopod 6 basis subrectangulate, 2.2 times as long as broad, anterior margin with robust setae, posterior margin weakly serrated. Pereopod 7 basis 1.7 times as long as broad. Epimeron 3 subquadrate, antero-ventral margin with two robust setae. Uropod 1 slender, peduncle and rami with robust setae; rami subequal in length and 0.8 times peduncle. Uropod 2 inner ramus 1.2 times outer ramus; outer ramus and peduncle subequal. Uropod 3 rami greatly elongated about 3.2 times length of peduncle; rami subequal, broad and ¯attened, inner ramus with a few setae on outer margin and a strong group of distal setae, outer ramus with many groups of setae on the outer margin. Telson almost fully cleft; lobes about three times as long as broad, notched at the tip with one robust seta inserted at the notch and one lateral to the notch.

Female. Length, 2.5 mm. Gnathopod 1 coxa antero-ventrally rounded; basis 3.3 times as long as broad without long setae on the posterior margin; carpus twice as long as broad; propodus 1.9 times as long as broad; other features similar to that of male. Gnathopod 2 coxa as long as broad; basis slender, three times as long as broad; carpus subtriangular, 1.2 times a long as broad; propodus subovate, 1.5 times as long as broad; palm oblique, palmar margin unexcavate and with numerous robust setae.

Remarks

The male of this species is characterized by the expanded basis of gnathopod 2. The symmetrical gnathopod 2, the smooth posterior margin of epimeron 3 and the long spatulate uropod 3, distinguish this species from all other Maera spp. with an oblique gnathopod 2 palm.

The present material agrees with the description of M. mooreana from Society Island ( Myers, 1989), diOEering only in the mandible palp article 3 having more medio-lateral setae.

Type locality. Moorea , Society Islands .

Distribution. Mauritius, Society Islands.