Ceradocus (Denticeradocus) alama, Myers, Alan A. & Nithyanandan, Manickam, 2016

Myers, Alan A. & Nithyanandan, Manickam, 2016, The Amphipoda of Sea City, Kuwait. — The Senticaudata (Crustacea), Zootaxa 4072 (4), pp. 401-429 : 421-424

Ceradocus (Denticeradocus) alama sp. nov.

( Figs 16–18 )

Type material. Holotype male, 7.0 mm ( NHMUK 2015. 3198) North Gate, collected from seaweed and hydroids growing on concrete sides of north tidal gate phase A3 by diving. D.K. Raja, 19 April 2014. Paratypes, 6 males, 9 females ( NHMUK 2015. 3199–3208), same data as holotype.

Other material. 9 males, 7 females ( NHMUK 2015. 3209–3218), llBS, grab on bare sand benthos in phase A1, M. Nithyanandan, 25 May 2014; 7 males, 9 females ( NHMUK 2015. 3219–3228), subtidal seagrass in phase A1 Sea City, Ocklemann sledge and small grab, M. Nithyanandan, 14 October 2014; 2 males ( NHMUK 2015. 3235–3236), from sandy benthos in phase A3 Sea City waterways, Ocklemann sledge, M. Nithyanandan, 20 October 2013.

Etymology. Named after a creek (Al-Ama) in the type locality. Description. Based on male holotype 7.0 mm.

Head. Eye lobe rounded with sub-ocular notch. Eye medium size, subround. Antenna 1 about two thirds body length; peduncular article 2 longer than 1, article 3 very short; accessory flagellum with 5 articles; primary flagellum longer than peduncle with 26 articles. Antenna 2 a little shorter than antenna 1; peduncular articles 4 and 5 subequal; flagellum with 24 articles. Maxilla 1 inner plate posterior margin fringed with setae. Mandible palp article 1 with acute spine at posterodistal corner; article 3 much shorter than 2 with long distal and marginal setae.

Pereon. Gnathopod 1 coxa with very acute anterodistal corner; carpus and propodus subequal in length, strongly setose. Right gnathopod 2 greatly enlarged; coxa subquadrate; basis stout with spine at anterodistal corner; carpus short, cup-shaped; propodus massive, subovoid, palm with short overhanging shelf, followed by a shallow U-shaped excavation, followed by an oblique undefined margin; dactylus stout, curved, fitting palm. Left gnathopod 2 much smaller than right gnathopod 2, similar in form and size to that of female. Pereopod 6 basis posterodistal margin with multiple spines. Pereopod 7 basis posterodistal margin with a single acute spine.

Pleon. Pleonal segments 1–3 strongly dorsally spinous with setae inserted between the spines. Epimera 1–3 posterior distal margins strongly spinous, with setae inserted between the spines, posterior margins with robust setae. Urosome segments 1–2 dorsally serrated with setae inserted between the spines. Uropod 1 peduncle a little longer than rami, with basofacial robust seta and with ventrodistal spine; inner ramus marginally longer than outer, slender with marginal and distal robust setae. Uropod 2 peduncle a little shorter than rami; inner ramus marginally longer than outer. Uropod 3 peduncle short; rami enlarged, broad, subequal in length.

Telson deeply cleft, lobes strongly divergent.

Female (sexually dimorphic characters) Gnathopod 2 coxa elongate, rounded, unproduced; basis weakly expanded anteromedially; carpus well developed, about two thirds length of propodus; propodus elongate subovoid, palm oblique, defined by a robust seta; dactylus slender, fitting palm.

Remarks. Ceradocus (Denticeradocus) alama sp. nov. resembles C. (D.) serratus ( Bate, 1862) , as figured by J.L. Barnard 1972 (not Megamoera serrata Bate, 1862 ) from Australia in the male large gnathopod 2 having a short palmar shelf and in not having a posterodistal defining spine. That species, however, does not have an excavation in the palm of the large male gnathopod 2. It is similar to C. (D.) serratus as figured by Ledoyer (1983) (also not Megamoera serrata Bate, 1862 ), but that species has a palmar defining corner lacking in C. (D). alama sp. nov. Like C. (D). alama sp. nov., the C. (D). serratus of Ledoyer, 1983 has a palmar excavation, but that excavation is much narrower than in C. (D). alama sp. nov. Ceradocus (D.) serratus of Ledoyer (1983) also lacks the palmar shelf characteristic of C. (D). alama sp. nov.

Distribution. Kuwait.

Figures

FIGURE 16. Ceradocus (Denticeradocus) alama sp. nov., male, 7.0 mm, female, 6.5 mm, Sea City, Kuwait.

FIGURE 17. Ceradocus (Denticeradocus) alama sp. nov., male, 7.0 mm, Sea City, Kuwait.

FIGURE 18. Ceradocus (Denticeradocus) alama sp. nov., male, 7.0 mm, Sea City, Kuwait.