A New Species of Parapleurocrypta Chopra, 1923 (Isopoda, Epicaridea, Bopyridae) Parasitizing Shrimps of the Genus Synalpheus Spence Bate, 1888 (Decapoda, Caridea, Alpheidae) from the Fernando de Noronha Archipelago, Brazil

Abstract

A new species of Parapleurocrypta Chopra, 1923, a parasitic isopod genus of the family Bopyridae found parasitizing two species of the snapping-shrimp genus Synalpheus Spence Bate, 1888, is described from Brazil. This is the first record of Parapleurocrypta in the Atlantic Ocean, and the first species of bopyrid parasite recorded from the Fernando de Noronha archipelago in northeastern Brazil. Females of Parapleurocrypta duofratres sp. nov. can be distinguished from the other two species of the genus, P. alphei Chopra, 1923 and P. digitata Bourdon, 1976, by the structure of the barbula, the reduced pleopods, the number of dorsolateral bosses, the absence of the frontal lamina (present in P. digitata), and pleomeres with lateral plates (vs. lateral plates absent in P. digitata). Males can be distinguished from those of P. alphei by the number of antennal articles. Variation in the specimens is discussed and ecological and reproductive data are provided. To accommodate the new features of P. duofratres sp. nov., the diagnosis of the genus is expanded. A review of the branchial bopyrids of Synalpheus is included, as well as a discussion of parasitism by members of Parapleurocrypta.

Keywords: Atlantic Ocean; Bopyrinae; Bopyroidea; Parasitism; Taxonomy.

Fig. 1.

Map of Fernando de Noronha archipelago, showing the six SCUBA diving locations where specimens of Synalpheus sp. parasitized by Parapleurocrypta duofratres sp. nov. were collected.

Fig. 2.

Parapleurocrypta duofratres sp. nov., female holotype (MZUSP #44176) and male allotype (MZUSP #44177), and host Synalpheus herricki Coutière, 1909 (DZ/UFRGS #7079). A, Female parasite habitus, dorsal view; B, Female parasite habitus, ventral view (with four eggs remaining in brood chamber); C, Host shrimp lateral view, arrow shows parasite in branchial chamber; D, Male parasite habitus, dorsal view. Scale bars: A–B = 0.5 mm; C = 0.5 cm; D = 0.3 mm.

Fig. 3.

Parapleurocrypta duofratres sp. nov., female holotype and paratypes. A, habitus, dorsal view (MZUSP #44176); B, habitus, ventral view (MZUSP #44176); C, antennules, antenna (shown on right side only), and oral cone (DZ/UFRGS #7006); D, barbula (DZ/UFRGS #7076); E, right oostegite 1, inner view (DZ/UFRGS #7006); F, right oostegite 1, outer view (DZ/UFRGS #7006); G, right maxilliped, outer view (DZ/UFRGS #7010); H, left pereopod 1 (DZ/UFRGS #7006); I, right pereopod 7 (DZ/UFRGS #7006); J, pleon, ventral view, with reduced pleopods on right side, absent on left side (DZ/UFRGS #6998). Scale bars: A–B = 0.5 mm; C = 0.05 mm; D = 0.25 mm; E–G = 0.2 mm; H = 0.1 mm; I = 0.15 mm; J = 0.4 mm.

Fig. 4.

Parapleurocrypta duofratres sp. nov., female paratype (DZ/UFRGS #7076), SEM. A, habitus, dorsal view; B, left antennule; C, right antenna (A1) and antennule (A2); D, left pereopod 1; E, left pereopod 7; F, right maxilliped, arrow shows maxilliped palp; G, long setae of right maxilliped palp, bearing spinous scales at the base and setules along length and tip; H, right oostegite 1, inner view; I, right oostegite 1, lateral projection of folded posterior lobe; J, right oostegite 1, inner surface with scales. Scale bars: A = 0.5 mm; B, I = 0.02 mm; C, G = 0.01 mm; D = 0.05 mm; E = 0.04 mm; F = 0.1 mm; H = 0.15 mm; J = 5 μm.

Fig. 5.

Parapleurocrypta duofratres sp. nov., male allotype and paratype. A, habitus, dorsal view (MZUSP #44177); B, habitus, ventral view (MZUSP #44177); C, left antennule and antenna (DZ/UFRGS #6986); D, right pereopod 1 (DZ/UFRGS #6986); E, left pereopod 7 (DZ/UFRGS #6986). Scale bars: A = 0.25 mm; B = 0.3 mm; C–E = 0.05 mm.

Fig. 6.

Parapleurocrypta duofratres sp. nov., male paratype (DZ/UFRGS #7076), SEM. A, habitus, ventral view; B, left antennule and antenna; C, right pereopod 1; D, right pereopod 7. Scale bars: A = 0.25 mm; B–D = 0.05 mm.