Linguimaera boeckoides, Hughes, Lauren E., 2016

Hughes, Lauren E., 2016, New genera, species and records of Maeridae from Australian Waters: Austromaera, Ceradocus, Glossomaera, Hamimaera, Huonella gen. nov., Linguimaera and Maeraceterus gen. nov. (Crustacea: Amphipoda), Zootaxa 4115 (1), pp. 1-81 : 43-45

Linguimaera boeckoides sp. nov.

( Figs 32–34 )

Type material. Holotype male, 5.4 mm, dissected, 4 slides, AM P.81529, Swiss Cheese Reef , Norfolk Island (29°00′23″S 167°56′50″E), 14 m, overhang, sponges, encrusting algae, 15 May 2008, coll. J.K. Lowry (MI NFK 38) . Paratypes: 1 male specimen, 5.1 mm, dissected in part, 1 slide (dominant left gnathopod), (damaged antennae and telson missing), AM P.81527, Emily Bay , Norfolk Island (29°03′36″S 167°57′12″E), 3.7 m, rubble on sand, 20 May 2008, coll. R.T. Springthorpe (MI NFK 82) ; 1 juvenile male specimen (right gnathopod dominant), AM P.81528, Fig Valley Reef , Norfolk Island (29°03′20″S 167°55′44″E), 19.7 m, near limestone reef sediment and some algae, 19 May 2008, coll. R.T. Springthorpe (MI NFK 65).

Type locality. Swiss Cheese Reef , Norfolk Island, South Pacific (29°00′23″S 167°56′50″E).

Etymology. Name for its similarity to Linguimaera boecki .

Description. Based on holotype male, 5.4 mm, AM P.81529.

Head. Eyes subovate; lateral cephalic lobe broad, rounded, apically rounded, anteroventral margin with notch/ slit, anteroventral corner rounded. Antenna 1–2 unknown. Mandible accessory setal row, well developed with 6 setae; palp well developed, article 1 length 2 × width, shorter than article 2; article 2 longer than article 3, with a few slender setae; article 3 rectilinear, long, 3.1 × as long as broad, longer than article 1, with 3 apical slender setae. Lower lip without apical ducts, mandibular lobes apically rounded. Maxilla 1 inner plate subquadrate, with 3 apical plumose setae (damaged, not illustrated).

Pereon. Gnathopod 1 coxa anterior margin concave, anteroventral corner produced, acute, posteroventral corner with notch; merus with posteroventral corner round; carpus length 2.9 × width, 1.3 × propodus length, setae covering medial surface; propodus subovate, medial surface setal comb absent; palm subacute, straight, entire, lined with robust setae, weakly defined by posterodistal corner; dactylus closing along palm.

Gnathopod 2 asymmetrical; larger gnathopod, subchelate; coxa posteroventral corner with notch; basis broad, anterodistal corner subquadrate; merus with acute posteroventral corner; carpus compressed, length subequal to width, anterior margin with a few slender setae, posterior margin with row of slender setae; propodus rectilinear, length 1.9 × width, margin with rows of short slender setae, palm angle subacute, distal shelf with 4 pairs of robust setae, palm margin with 1 subacute tooth and defined by posteroventral corner with tooth; dactylus closing along palm, apically rounded, unguis absent. Gnathopod 2 smaller gnathopod basis slender, anterodistal corner subquadrate; merus with acute posteroventral corner; carpus subtriangular, length 2.1 × width, margins with long slender setae; propodus rectilinear, length 3.8 × width, margin with rows of long slender setae, palm angle subacute, margin straight, lined with robust setae, without palm defining corner; dactylus closing along and reaching end of palm, unguis present.

Pereopods 5–7 slender distally; basis posterior margin straight, serrate; merus, carpus and propodus not broadened, with a few long slender setae distally; dactylus unguis simple.

Pleon. Pleonites 1–3 dorsally smooth. Epimera 1–2 posterodistal corner with notch. Epimeron 3 posterodistal margin serrate, posteroventral corner with notch. Urosomites 1–3 without carina. Uropod 1 peduncle with 1 basofacial seta, peduncle length 1.6 × outer ramus; inner ramus longer than outer ramus. Uropod 2 peduncle length 1.1 × outer ramus; inner ramus longer than outer ramus. Uropod 3 rami subequal in length, longer than peduncle, length 3 × width, distally truncated, with lateral and apical long and short robust setae. Telson cleft (55%), length subequal to width, lobes divergent, tapering distally, with longer outer and shorter inner cusps, apically acute, margins concave, each lobe with 1 short and 1 long apical robust setae, without marginal or lateral robust setae.

Variation. Material examined included individuals that were either left or right dominant for male gnathopod 2.

Remarks. Linguimaera boeckoides sp. nov. from Norfolk Island is very similar to L. boecki in all but two characters, which are the presence of long slender setae on the lower article of pereopods 5–7 and the absence of lateral robust setae on the telson .

Distribution. Norfolk Island: Swiss Cheese Reef, Emily Bay, Fig Valley (current study).

Figures

FIGURE 32. Linguimaera boeckoides sp. nov., holotype male, habitus 5.4 mm, AM P. 81529, Swiss Cheese Reef, Norfolk Island.

FIGURE 33. Linguimaera boeckoides sp. nov., holotype male, 5.4 mm, AM P. 81529, Swiss Cheese Reef, Norfolk Island, scales 0.1 mm.

FIGURE 34. Linguimaera boeckoides sp. nov., holotype male, 5.4 mm, AM P. 81529, Swiss Cheese Reef, Norfolk Island, scales 0.1 mm.