Plumithoe boulari, Peart & Hughes, 2013

Peart, R. A. & Hughes, L. E., 2013, Ampithoid amphipods from the South Pacific: Papua New Guinea, French Polynesia and New Caledonia, Journal of Natural History (J. Nat. Hist.) 48 (13 - 14), pp. 739-861 : 838-844

Plumithoe boulari sp. nov.

( Figures 75–78 )

Type material

Holotype male, 3.5 mm, dissected, three slides, AM P.84624, off Recif To, Passe de Boulari , New Caledonia (22 ◦ 30.15 ′ S, 166 ◦ 26.43 ′ E), 13 m, coral rubble, 8 November 1995, coll. ORSTOM divers Jean-Louis Menou, Georges Bargibant, Pascal Hamel, Stéphane Bujan (NCL-47) . Paratype female, 4 mm, dissected, one slide, AM P.84625; paratypes 34 specimens, AM P.84626, same location as holotype .

Type locality

Recif To, Passe de Boulari , New Caledonia (22 ◦ 30.15 ′ S, 166 ◦ 26.43 ′ E) .

Etymology

The name is after the type locality, applied as a noun in apposition.

Additional material examined

New Caledonia: few specimens, AM P.84627, off Recif To , Passe de Boulari (22 ◦ 30 ′ 09 ′′ S, 166 ◦ 26 ′ 26 ′′ E), 32 m, green alga, 8 November 1995, coll. I. Takeuchi (NCL-49); several specimens, AM P.84628, Grand Recif Mbere (22 ◦ 19 ′ 54 ′′ S, 166 ◦ 13 ′ 14 ′′ E), 12–25 m, coarse rubble, 21 November 1995, coll. J.K. Lowry (NCL-154) .

Diagnosis

Antenna 1 primary flagellum with 22 articles. Antenna 2 flagellum with 15 articles. Mandible accessory setal row with three robust setae (four on left). Maxilla 1 inner plate with one plumose seta; outer plate palp well-developed, slender; article 2 with four apical robust setae. Gnathopod 1 coxa anterior margin straight, anteroventral corner produced, rounded; basis shorter than coxa, with sparse slender setae, with single anterodistal lobe large, round; carpus subtriangular; propodus subovoid, length twice width, palm subacute to acute, convex, defined by weak rounded corner with one robust seta. Gnathopod 2 coxa ventral margin with row of small setules; basis length subequal to coxa, with sparse slender setae, anterodistal corner subquadrate; merus anteroventral margin truncate; carpus subtriangular; propodus subrectangular, palm nearly transverse, shallowly excavate, defined by subquadrate corner with one robust seta, palm length 0.3 times posterior margin. Telson subovate, apically convex, with one pair of apical slender setae, one pair of apical plumose setae and two pairs of lateral slender setae.

Description

Based on holotype male, 3.5 mm, AM P.84624.

Head. Antenna 1 longer than antenna 2; peduncular article 1 length 1.3 times article 2; article 2 length 2.2 times article 3; article 3 length 0.3 times article 1; primary flagellum with 22 articles; accessory flagellum absent. Antenna 2 slender, similar to antenna 1; peduncular articles 3–5 with long, dense setae on ventral margin; peduncular article 4 subequal to article 5; flagellum with 15 articles. Epistome and upper lip angle directed nearly straight down, around 90 degrees. Upper lip distally setose. Mandible molar well-developed, triturating; accessory setal row with three robust setae (four on left); palp tri-articulate, slender; article 2 with single seta; article 3 length 3.1 times width. Lower lip outer plate notched; outer lobe longer than inner lobe; mandibular lobe with curved margins, apically rounded. Maxilla 1 inner plate with one plumose seta; outer plate palp well-developed, slender; article 2 with four apical robust setae. Maxilla 2 inner plate narrow; outer plate broader. Maxilliped outer plate with large robust setae.

Pereon. Coxae 1–4 longer than broad. Gnathopod 1 smaller than gnathopod 2; coxa 1 larger than coxa 2, anterior margin straight, anteroventral corner produced, rounded, ventral margin with a row of small setules; basis shorter than coxa, with sparse slender setae, with single anterodistal lobe large, round; merus anteroventral corner subacute; carpus subtriangular, length 1.3 times width, 0.6 times propodus length; propodus subovoid, length twice width, palm subacute to acute, convex, defined by weak rounded corner with one robust seta; dactylus overreaching palm, apically subacute, tapering evenly, posterior margin denticulate. Gnathopod 2 coxa ventral margin with row of small setules; basis length subequal to coxa, with sparse slender setae, anterodistal corner subquadrate; merus anteroventral margin truncate; carpus subtriangular, length subequal to width, 0.6 times propodus length; propodus subrectangular, length twice width, palm nearly transverse, shallowly excavate, defined by subquadrate corner with one robust seta, palm length 0.3 times posterior margin; dactylus subequal in length to palm, apically acute, tapering evenly, posterior margin denticulate. Pereopods 3–4 basis and merus narrow. Pereopods 5–7 basis without marginal robust setae; merus subrectangular; dactylus recurved.

Pleon. Epimera 1–2 posteroventral corner narrowly rounded. Epimeron 3 posteroventral corner subquadrate. Uropod 1 long, reaching end of uropod 2 rami; peduncle length 2.3 times width, with five robust setae, distoventral spine large, acute; inner ramus 0.8 times peduncle length, longer than outer ramus, with one marginal robust seta; outer ramus with one marginal robust seta. Uropod 2 peduncle with three robust setae, with short distoventral spine; inner ramus longer than outer ramus, with one marginal robust seta; outer ramus with one marginal robust seta. Uropod 3 peduncle length 1.7 times width, with two distal robust setae; inner ramus length 1.8 times as long as broad, 0.7 times peduncle length with three distal robust setae, without lateral robust setae; outer ramus subequal to inner ramus, with two large recurved distal robust setae, with one slender and one robust lateral setae. Telson subovate, apically convex, subsubapical cusps small, with one pair of apical slender, one pair of apical plumose and two pairs of lateral slender setae.

Female (sexually dimorphic characters)

Description based on paratype, 4 mm, AM P.84626.

Pereon. Gnathopod 1 subequal to gnathopod 2. Gnathopod 2 basis shorter than coxa; propodus subovoid, palm convex.

Habitat

Specimens collected from coral rubble and green algae.

Remarks

The male gnathopod 2 propodus palm without an acute tooth aligns Plumithoe boulari sp. nov., P. plumicornis ( Ledoyer 1979b) and P. quadrimanus ( Haswell 1879) . Plumithoe boulari sp. nov. is most similar to P. plumicornis from Madagascar, in the male gnathopod 2 propodus palm concave. Plumithoe boulari sp. nov. differs from the P. plumicornis in the antennae 1 flagellum with more than 20 articles and the presence of medial and lateral slender setae on the telson.

Distribution

New Caledonia (current study).

Figures

Figure 75. Plumithoe boulari sp. nov., holotype male 3.5 mm, AM P.84624; paratype female 4 mm, AM P.84626, New Caledonia.

Figure 76. Plumithoe boulari sp. nov., holotype male 3.5 mm, AM P.84624; paratype female 4 mm, AM P.84626, New Caledonia. Scale bars 0.2 mm.

Figure 77. Plumithoe boulari sp. nov., holotype male 3.5 mm, AM P.84624; paratype female 4 mm, AM P.84626, New Caledonia. Scale bars 0.2 mm.

Figure 78. Plumithoe boulari sp. nov., holotype male 3.5 mm, AM P.84624, New Caledonia. Pereopod scales 0.2, all other scale bars 0.1 mm.