Munidopsis trindadensis Cardoso, Serejo & Rodrigues, 2014, sp. nov.
Creators: name: Cardoso, Irene A.
name: Serejo, Cristiana S.
name: Rodrigues, Celso
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Galatheidae
Munidopsis
Munidopsis trindadensis

description: Munidopsis trindadensis sp. nov.
(Figs. 1, 2)
Holotype. REVIZEE: st. 41C, 20°30’13”S /29°16’105”W, 360 m, 10/VII/2001, 1 male, CL: 6.6 mm, CW: 5.2 mm, MNRJ 16496.
Type locality. Off Trindade Island, Espírito Santo, 20º30’13”S /29º16’105”W, 360m.
Diagnosis. Carapace with numerous short striae, with many dorsal spines; frontal margins oblique, outer orbital angle acute; anterolateral spine stout, curved inwards; lateral margins with 3 stout spines. Rostrum width about one-fifth distance between anterolateral spines; exceeding one-third remaining carapace length; apex bluntly pointed; lateral margins finely serrate. All sternites with smooth surfaces. Abdominal tergites smooth and unarmed; tergites 2–4 with elevated anterior ridge and shallow transverse groove behind anterior ridge. Ocular peduncle movable, with strong divergent spine. Antennular basal segment with three spines, dorsal shorter. Cheliped 1.8 times carapace length; pollex and dactylus with simple apices. Pereopods 2–4 densely spinose and tuberculate; carpus with 2 or 3 rows of teeth; merus extensor and flexor margins dentate, most prominent on anterior two pereopods. Pereopods without epipods. Telson subdivided into 7 plates.
Description. Carapace as long as wide; flattened from side to side, densely covered with horizontal setose striae; with eight epigastric spines; gastric region strongly convex; hepatic and epibranchial regions well defined, the last with 2 spines at each side; cardiac region strongly convex, anterior carina with 4 spines; 3 post-cervical spines at each side; deep meso-cardiac sulcus, without tubercles; branchial region with 5 spines at each side; without cervical groove, with a distinct post-cervical groove; frontal margins oblique, outer orbital angle acute; anterolateral spine stout, curved inwards; lateral margins convex, widest at level of branchial region; anterior lateral margins with 3 strong teeth, posterior lateral margins irregularly serrate; posterior margin with a strong carina bearing 9 stout spines curved forwards (Fig. 1 A, B).
Rostrum width about one-fifth distance between anterolateral spines; length exceeding one-third remaining carapace length; apex bluntly pointed, straight; lateral margins finely serrate; carinate dorsally (Fig. 1 A, B). Pterygostomian region with striae; anterior apex acute.
Sternum slightly wider than long; widest at sternite 7. Sternite 3 about one-fourth width of sternite 4; all sternites with anterior margins crenulate (Fig. 1 C). Sternites 3–7 smooth (Fig. 1 C).
Abdominal tergites smooth and unarmed (Fig. 1 A, B). Tergites 2–4 with elevated anterior ridge and shallow transverse groove behind anterior ridge, deeper of tergite 2 and shallowest of tergite 4; tergite 5 without transverse groove; tergite 6 with sinuous posterior margin (Fig. 1 A, B). Telson composed of 7 plates (Fig. 1 D).
Ocular peduncle movable, with strong divergent spine overreaching cornea (Fig. 1 A, B). Cornea subglobular, as wide as the peduncle (Fig. 1 A, B).
Antennular peduncle basal segment with 3 spines, dorsal shorter; distal margin near the flagellum crenulate (Fig. 2 A). Antennal peduncle basal segment with acute mesial and lateral tooth; segment 2 with stout distolateral spine and a small subdistal spine; distomesial margin angular; segment 3 with 3 spines and segment 4 with 2 spines (Fig. 2 A).
Maxilliped 3 dactylus, propodus and carpus setose, unarmed; merus without distal extensor spine; flexor margin with 3 stout teeth (Figure 2 B); crista dentata with 17–19 corneous denticles.
Right pereopod 1 (cheliped) 1.8 times longer than carapace, densely spinose and tuberculate; propodus with 5 stout teeth at extensor margin, flexor margin with numerous small teeth, dorsal and ventral surfaces with sparse striae, palm about 2.2 times as long as high; fixed finger and dactylus with dentate occlusal margins, fixed finger with acute apex and dactylus with simple apex; carpus and merus with three rows of strong teeth, at flexor and extensor margins and at mesial surface; ischium with dorsodistal tooth (Fig. 2 C).
Pereopod 2–4 dactylus curved, flexor margin setose, terminating in corneous unguis (Fig. 2 D–F). Pereopod 2 reaching anterior margin of pereopod 1 carpus. Pereopods 2–3 propodus tuberculate, extensor margin dentate; carpus extensor margin dentate, with a distal spine, dorsal margin with a row of small tubercles; merus extensor and flexor margins dentate, with distal spines (Fig. 2 D, E). Pereopod 4 propodus, extensor margin dentate, dorsal surface with a proximal row of teeth; carpus extensor margin dentate, with a distal spine, dorsal margin with two rows of teeth, distal margin serrate; merus extensor margin dentate with a distal spine, dorsal margin densely dentate (Fig. 2 F). Ischium unarmed at pereopod 2, with 3 blunt teeth and a dorsodistal tooth at pereopod 3; with 3 rows of small blunt teeth at pereopod 4 (Fig. 2 D–F).
Pereopods without epipods.
Etymology. Derived from the type-locality, Trindade Island, southwestern Atlantic.
Distribution. Southwestern Atlantic, off Trindade Island, Espírito Santo, Brazil.
Remarks. All the six Munidopsis species previously recorded from the southwestern Atlantic (M. barbarae, M. erinacea,; M. nitida, M. sigsbei, M. riveroi and M. transtridens) have a telson with eight or more plates while M. trindadensis sp. nov. presents seven plates. Munidopsis erinacea is the only species in the area that can have seven, eight or more plates on the telson, but it can be distinguished from M. trindadensis sp. nov. by the rostrum having a pair of large lateral spines.
Characters such as the triangular and dorsally carinate rostrum; prominent antennal spine; conical, divergent spine on the cornea; smooth abdomen and the absence of epipods on the pereopods are shared with Munidopsis trindadensis sp. nov., M. acutispina Benedict, 1902, M. penescabra Pequegnat & Williams, 1995, M. kucki Baba & Camp, 1998, M. sharreri (A. Milne Edwards, 1880), M. tanneri Faxon, 1893 and M. scabra Faxon, 1893. Munidopsis acutispina and M. kucki occur in the northeastern Atlantic, the first differs from M. trindadensis sp. nov. mainly by the unarmed rostrum and the lateral carapace margins with five spines (Pequegnat & Williams 1995). The second can be distinguished from M. trindadensis sp. nov. by the carapace lacking spines on the posterior margin and the telson with eight plates (Pequegnat & Williams 1995).
Munidopsis sharreri occurs in the Caribbean Sea and differs from M. trindadensis sp. nov. by having a carapace covered with scale-like tubercles that are never developed into acute spines and a telson with eight plates (Pequegnat & Pequegnat 1971).
Munidopsis penescabra was described from the Gulf of Mexico and differs from M. trindadensis sp. nov. mainly by the lateral carapace margins having six or seven spines, the carapace with a more spinose dorsal surface and the shape of cardiac region (Pequegnat & Williams 1995).
Munidospsis tanneri and M. scabra occur in the eastern Pacific; the first differs from M. trindadensis sp. nov. by the slender rostrum and the quadrangular carapace being wider in the posterior half; Munidopsis scabra differs from M. trindadensis sp. nov. mainly in the spination of the lateral carapace margins with 8–10 spines (versus 6 spines) (Pequegnat & Williams 1995).
description: Published as part of Cardoso, Irene A., Serejo, Cristiana S. & Rodrigues, Celso, 2014, A new Munidopsis species (Galatheoidea, Munidopsidae) from the Southwestern Atlantic, pp. 441-446 in Zootaxa 3815 (3) on pages 442-445, DOI: 10.11646/zootaxa.3815.3.10, http://zenodo.org/record/224898