Parapronoe parva Claus, 1879

Gasca, Rebeca & Hendrickx, Michel E., 2021, Pelagic amphipods (Crustacea: Amphipoda: Hyperiidea) in western Mexico. 2 Family Eupronoidae, Zootaxa 4948 (3), pp. 419-430 : 423

Parapronoe parva Claus, 1879

Parapronoe parva Claus, 1879:31 Vinogradov , et al. 1996:460; Gasca & Franco-Gordo, 2008: 569 (table 1); Gasca, 2009: 88 (list); Gasca et al., 2012: 126 (table 1); Zeidler, 2016:27, 28, 31 (key); Lavaniegos & Hereu, 2009: 142 (table 1), 152 (ap- pendix 1): Lavaniegos, 2014: 4 (table 1). Sympronoe anomala Shoemaker, 1925:42 . Parapronoe parva parva .— Siegel-Causey, 1982: 292. Parapronoe parva septemarticulata .— Siegel-Causey, 1982: 294.

Material examined. 3M and 11F from 7 stations ( Fig. 4 ). TALUD I. St. 5 (ca. 23°16’N, 107°31’W), December 11, 1989 , 1F, BO, from surface to ca. 200 m ( TD > 1500 m) (ICML-EMU-12770-A) . TALUD III. St. 3B (22°36’36”N, 106°35’54”W), August 17, 1991 , 6F, I-K, from surface to 275 m ( TD ND) (ICML-EMU-12770-B); St. 19 (25°12’00”N, 109°07’00”W), August 20, 1991 , 1F, I-K from surface to 410 m ( TD 920 m) (ICML-EMU- 12770-C) . TALUD IV. St. 7 (22°21’39”N, 107°01’42”W), March 14, 2001 , 3F, MN from surface to 1305 m ( TD 2100 m) (ECO-CH-Z-10371) . TALUD VI. St. 22 (24°17’34”N, 108°50’25”W), March 15, 2001 , 1M, MN from surface to 1410 m ( TD 1760 m) (ICML-EMU-12771-A) . TALUD X. St. 7 (27°53’09”N, 112°16’42”W), February 10, 2007 , 1M, MN from surface to 900 m ( TD 1191 m) (ICML-EMU-12771-B) . TALUD XII. St. 4 (24°17’34”N, 108°50’25”W), March 28, 2008 , 1 M, MN, 1380 m ( TD 1995 m) (ECO-CH-Z-10372) .

Distribution. Circumtropical. In the eastern Pacific it has been recorded from the Gulf of California, western Mexico, to Peru ( García-Madrigal 2007), and from off the west coast of the Baja California Peninsula ( Lavaniegos & Hereu 2009; Lavaniegos 2014, 2017).

Remarks. Two of the smallest specimens of P. parva in our samples (TALUD III. St. 3B) had one 5-segmented pereopod VII (as the pereopod VII in Sympronoe anomala ) and the other with seven segments, as in P. parva septemarticulata . The variability in the pereopod VII segmentation has been considered an intraspecific variation for P. parva ( Shoemaker 1945; Vinogradov et al. 1996; Zeidler 2016).

According to Siegel-Causey (1992), P. parva (cited as the subspecies P. p. parva ) is rare in the Gulf of California and occurred only in four localities in the southern gulf. The specimens reported by Siegel-Causey (1982) as P. p. septemarticulata occurred in the same area as the nominal subspecies. Brusca & Hendrickx (2005) reported both subspecies in the Gulf of California, based on Siegel-Causey’s (1982) report. They reported P. p. septemarticulata as endemic to the central and southern gulf, a consideration no longer valid. In the case of P. p. parva, Brusca & Hendrickx (2005) correctly reported this subspecies as cosmopolitan, recorded in the Indian, Pacific and Atlantic Oceans, but with a rather limited distribution in the eastern Pacific: from 27°30’N, 110°28’W to off Los Frailes, in the Gulf of California. However, according to García-Madrigal (2007), this subspecies also occurs off Michoacan (17°50’40”N, 103°01’10”W), SW Mexico, and further south to Peru. Parapronoe parva has been reported also from Banderas Bay ( Gasca & Franco-Gordo 2008) and from Punta Farallón, Jalisco, Mexico (19°19’77”N, 105°00’28”W) to Cuyutlán, Colima, Mexico (18°58’24”N, 104°13’51”W), in the Mexican Pacific ( Gasca et al. 2012). In our study, Parapronoe parva was found at six stations ( Fig. 3 ), with the northernmost sample taken at 27°53’09”N, slightly to the north of its previous northernmost distribution limit. The southernmost sample was collected off southwestern Mexico (16°59’39”N, 100°58’07”W) and represents the only sample of Eupronoidae found south of the Gulf of California during our study. Parapronoe parva is distinguished from its congeners by the telson being about or less than half the length of uropod 3, with distal margin rounded, and uropods III with endopods and exopods featuring a rounded terminal margin ( Zeidler 2016).

Figures

FIGURES 3–4. 3. Localities where Eupronoe minuta Claus, 1879, was captured during this survey. 4. Localities where Parapronoe parva Claus, 1879, was captured during this survey.