Periclimenaeus aff. atlanticus ( Rathbun, 1901 )

Fransen, Charles H. J. M., 2023, The marine palaemonid shrimps (Crustacea, Deapoda, Caridea) of the Dutch Caribbean, Zootaxa 5387 (1), pp. 1-127 : 36-38

publication ID	https://doi.org/ 10.11646/zootaxa.5387.1.1
publication LSID	lsid:zoobank.org:pub:0AD29F74-D349-4E12-8CA4-310275A847B3
DOI	https://doi.org/10.5281/zenodo.10390026
persistent identifier	https://treatment.plazi.org/id/03B787A1-FFC2-025C-FF5F-FCB7FB54F8E2
treatment provided by	Plazi
scientific name	Periclimenaeus aff. atlanticus ( Rathbun, 1901 )
status

Treatment

Periclimenaeus aff. atlanticus ( Rathbun, 1901) View in CoL

( Figs. 16–17 View FIGURE 16 View FIGURE 17 )

Material examined. Curaçao: ZMA. CRUS.D.103185: 1 juvenile, P2 minor missing , R =3/0, pocl. 0.6 mm; St. Michiel , 14.v.1976, depth 3 m, in S. vesparium , collected by P. Hoetjes (fcn. S-140576-I) . ZMA. CRUS.D.103220: 2 specimens, pocl. 1.1 mm , R =3/0; pocl. 1.4 mm, R =4/0, material damaged, dried out; near Blauwbaai , 11.ii.1976, depth 20 m, from Agelas dispar Duchassaing & Michelotti, 1864 , collected by P. Hoetjes (fcn. A-110276-I) .

Remarks. The present specimens are very small (pocl. 0.6 mm) even smaller than the two female type specimens (total length 5.0 and 5.5 mm) described by Rathbun (1901) and redescribed by Holthuis (1951b). Rostra of present specimens with three or four dorsal teeth of which distalmost small, whereas type-specimens of P. atlanticus with four equally developed teeth dorsally; rostrum distally slightly upturned, not overreaching cornea nor basal segment of antennular peduncle ( Fig. 16A, B View FIGURE 16 ) whereas just overreaching basal segment of antennular peduncle in type specimens of P. atlanticus . Carapace without supraorbital tooth or tubercle; inferior orbital angle slightly developed ( Fig. 16B View FIGURE 16 ). Scaphocerite relatively long, distincly overreaching antennular peduncle ( Fig. 16B View FIGURE 16 ), whereas not overreaching penultimate segment of antennular peduncle in P. atlanticus ; distolateral tooth of scaphocerite moderately developed, reaching distal margin of lamina, whereas more strongly developed in types of P. atlanticus . Carpocerite short ( Fig. 16B View FIGURE 16 ), reaching midlength of scaphocerite whereas overreaching distal lamina of scaphocerite in types of P. atlanticus . Antennal tooth robust. Infraorbital margin angular, not produced. Pterygostomial margin rounded, not produced ( Fig. 16A View FIGURE 16 ). Second pereiopods equal in size, unequal in shape. Major chela with few acute tubercles along median margin of ischium and merus; carpus cup shaped; palm swollen; fixed finger with distinct fossa, medially flanked by triangular knob, distal cutting edge entire, tip strongly hooked; movable finger with well developed plunger, distal cutting edge denticulate, tip strongly hooked ( Fig. 17A View FIGURE 17 ). Both minor cheliped fingers with crenulated tooth in proximal part of cutting edge; distal part of cutting edge finely denticulate, more extensive in dactylus than in fixed finger ( Fig. 17B View FIGURE 17 ). According to Holthuis (1951b) these shallow denticles are not present on the cutting edge of the fixed finger in the type material of P. atlanticus . Third pereiopods with distoventral part of propodus ( Fig. 17C, D View FIGURE 17 ) with one subdistal ventral and one distoventral spine, both minutely tuberculate on flexor margin; dactylus slender with flexor margin of corpus with small obliquely forward directed accessary tooth and acute, slightly forward directed, posterior tooth. This posterior tooth is mentioned by Rathbun (1901) but not shown in the drawing ( Fig. 28c View FIGURE 28 ) whereas it is not mentioned in the description by Holthuis but visible in his plate 24, figure o. Fifth pereiopod ( Fig. 17E, F View FIGURE 17 ) similar to third, propodus with only few distolateral serrulate setae. First abdominal somite without anterior median dorsal lobe. Sixth abdominal segment with posterolateral margin with small tooth ( Fig. 16C View FIGURE 16 ). Distolateral margin of exopod of uropod without tooth, with small mobile spine just medially of distolateral angle ( Fig. 16C View FIGURE 16 ). Dorsal pairs of spines on telson of moderate length; anteriormost pair at 0.25 of telson length, posteriormost pair at 0.55 of telson length ( Fig. 16C View FIGURE 16 ). This differs from P. atlanticus where the anterior pair is placed at about 0.4 and and the posterior pair at 0.75 of the telson length. Lateral pair of terminal spines placed almost in line with other terminal spines, not disctinctly subdistal or submarginal ( Fig. 16D View FIGURE 16 ).

The specimens at hand are in a bad condition and very small. Although there are similarities with P. atlanticus , there are also some clear differences. It is therefor not possible to identify them here with full certainty.

Ecology. Previous records of the species did not mention a potential host ( Holthuis, 1951b). The present specimens were found in two poriferan hosts: S. vesparium , and A. dispar .

Distribution. Records of P. atlanticus are scarce: St. Thomas, Virgin Islands ( Rathbun 1901); Isla de Cozumel and Bahía de la Ascención, Quintana Roo, Mexico ( Chace 1972); Indian River, East Florida ( Reed et al. 1982); in depths between 6 and 42 m. This is the first record of the species from Curaçao, if conspecific.