Order Amphipoda Latreille, 1816
Suborder Senticaudata Lowry & Myers, 2013
Superfamily Caprelloidea Leach, 1814
Family Caprellidae Leach, 1814
Subfamily Caprellinae Leach, 1814
Genus Paracaprella Mayer, 1890
Paracaprella pusilla Mayer, 1890 (Fig. 2)
Paracaprella pusilla Mayer 1890: 41, pl.1 Figs. 28–30; Mayer 1903: 67, pl.2 Figs. 36–37; Schellenberg 1928: 677–678; Edmondson and Mansfield 1948: 208–209, Fig. 4; Barnard 1955: 99; Day and Morgan 1956: 303; Steinberg and Dougherty 1957: 283–284, Figs. 16, 19, 24, 30; McCain 1968: 82, Figs. 32a-b, 41, 42, 53; Wakabara et al. 1991: 73; Serejo 1998: 381, Fig. 7; Wakabara and Serejo 1998: 585; Guerra-García and Thiel 2001: 880, Fig. 8; Díaz et al. 2005: 23, Fig. 13; Guerra-García et al. 2006: 175, Figs. 17–19; Montelli and Lewis 2008: 38, Fig. 5; Bhave and Deshmuk 2009: 112, Figs. 1–2; Lacerda and Masunari 2011: 372, Fig. 3a; Ros et al. 2013a: 679, Fig. 2; Alarcón-Ortega et al. 2015: 213, Fig. 2; Mauro and Serejo 2015: 121–123, Figs. 10–12; Alfaro-Montoya and Ramírez-Alvarado 2018: 281, Fig. 2; Lo Brutto et al. 2019: 664, Fig. 3.
Material examined
222 males, 182 mature females, 70 immature females, 89 juveniles (Table 2). 20 males, 20 mature females, 20 immature females and 20 juveniles were deposited in the Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima, Peru (MUSM-INV 4820–4827).
Habitat
The specimens of P. pusilla were collected of culture lanterns of bivalves Argopecten purpuratus and Pteria sterna, and were mainly associated with hydrozoan Ectopleura cf. crocea and bryozoan Bugula neritina at Sechura and Samanco Bays, Peru.
Diagnosis
Males, head without projection; peduncle of antenna 1 usually longer than antenna 2 (Fig. 2a); antenna 2 without swimming setae but densely setose; Pereonite 2 with a large acute projection on its anterolateral margin and a small tubercle on its anterodorsal margin (Fig. 2a, b); Gnathopod 2 with a proximal protuberance at the base, while the palmar margin of the dactylus with setae and a trapezoidal projection (Fig. 2c); gills in Pereonites 3–4, and Pereonite 3 with a more developed lateral pleura compared to the lateral pleura of Pereonite 4; Females with a pair of brood pouch on Pereonites 3–4 (Mayer, 1903; McCain, 1968) (Fig. 2a, d).
Distribution
Brazil; Hawaii; Australia; Panama; Mexico; Costa Rica; India; Mediterranean Sea.
Table 2
Mean body lengths (mm) of Paracaprella pusilla at two localities of the Peruvian coast in the Southeast Pacific. N = number of specimens; Min = minimum value (mm); Max = maximum value (mm); SD = standard deviation
Sex/age | Locality | N | Mean ± SD | Min | Max |
Males | Samanco Bay | 132 | 7.09 ± 1.80 | 4.00 | 11.56 |
Sechura Bay | 90 | 7.20 ± 1.71 | 5.00 | 11.85 |
Mature females | Samanco Bay | 102 | 4.89 ± 0.93 | 3.17 | 7.08 |
Sechura Bay | 80 | 5.13 ± 0.66 | 3.98 | 7.47 |
Immature females | Samanco Bay | 39 | 3.21 ± 0.46 | 2.16 | 3.93 |
Sechura Bay | 31 | 3.67 ± 0.42 | 2.56 | 4.59 |
Juveniles | Samanco Bay | 50 | 3.16 ± 1.10 | 1.11 | 5.03 |
Sechura Bay | 39 | 4.20 ± 0.57 | 3.27 | 5.31 |