Clausidium persiaensis Sepahvand and Kihara, 2017

Clausidium persiaensis Sepahvand and Kihara View in CoL sp. nov.

( Figs. 2–12 View Figure 2 View Figure 3 View Figure 4 View Figure 5 View Figure 6 View Figure 7 View Figure 8 View Figure 9 View Figure 10 View Figure 11 View Figure 12 )

Type material. Holotype: dissected female on 25 slides ( ZUTC 5913 ), 14.V.2015 . Allotype: dissected male on25 slides( ZUTC,5914);undissected paratypes 21 couples ( ZUTC 5915 ) deposited in ethanol at the Zoological Museum , University of Tehran Crustacean collection, Tehran, Iran. All material collected from the type locality by Vahid Sepahvand .

Type locality. Persian Gulf , Iran ( Qeshm Island, Parke-zeyton 27º81’06”N 56º24’11”E, Fig. 1 View Figure 1 ). Specimens collected from the gill chambers of the ghost shrimp Callianidea typa .

Description. Female:total length 1.31–1.36 mm (N = 10).Greenishincolorwhenalive.Bodybroadlyrounded ( Figs. 8A, B View Figure 8 , 11A, B View Figure 11 ), dorsoventrally compressed. Prosome ( Fig. 8A, B View Figure 8 ) 2.5 times longer than urosome. Maximum width measured at posterior margin of second pedigerous somite. First pedigerous somite fused with cephalosome, forming cephalothorax. Body prosomites with minute integumental pits, sensilla and numerous pores distributed as illustrated in figures. Epimera of second and third pedigerous somites expanded posteriorly.Fourth pedigerous somite almost as long as the two anterior somites combined. Posterior margin of fourth pedigerous somite rounded.

Urosome ( Figs. 5A, B View Figure 5 , 8B View Figure 8 ) 3–segmented, distinctly narrower than prosome. Urosome comprising fifth pedigerous somite, genital double-somite and anal somite. Somite bearing P5 ( Fig. 8B View Figure 8 ) 2.3 times wider than long in ventral view and with P5 arising ventrolaterally.Genital double-somite ( Figs.5 View Figure 5 , 9 View Figure 9 ) wider than long. Genital apertures located dorsolaterally on each side (showed with white arrow in Fig. 12A View Figure 12 ), near fifth pedigerous somite posterior margin. Medial pore presence (showed with blue arrow in Fig. 12A View Figure 12 ) in dorsal surface.Anal somite ( Figs.9 View Figure 9 , 12 View Figure 12 ) well developed, formed by second to fourth abdominal somites fused into one single segment; almost quadrate, incised medially, with intricate folders dorsally and along lateral margins, outer corners swollen and with special convoluted pattern as illustrated in figures. Caudal rami ( Figs.2B View Figure 2 , 9 View Figure 9 ) about 5 times longer than wide, and armed with 6 setae. Rostrum ( Figs. 6A View Figure 6 , 8B View Figure 8 ) incorporated into cephalothorax, with broad posteroventral margin.

Antennule ( Figs. 2B View Figure 2 , 8B View Figure 8 ) 7-segmented. Segment 2 longest, with long seta inserted on inner distal corner and almost reaching the tip of segment 5. Aesthetascs inconspicuous. Segment 7 with apical acrothek consisting of aesthetasc and 2 setae. Armature formula: I-[5], II-[15]III-[6], IV-[3], V-[5], VI-[3], VII-[8]. Antenna ( Figs. 7C View Figure 7 , 8C View Figure 8 ) 4-segmented. Coxobasis elongated, with row of spinules along inner margin, with single seta on inner distal corner. Endopod 3-segmented; segment 1 with small seta along the inner margin; segment 2 with 2 pectinate spines and 2 setae (1 pinnate and 1 naked); segment 3 with 6 apical setae (2 pectinate, 2 pinnate and 2 naked).

Labrum ( Figs. 3C View Figure 3 , 8C View Figure 8 ) 2 times wider than long; distal area and lateral projections with row of long setules. Metastomal area ornamented as in Fig. 3C View Figure 3 . Mandible ( Fig. 3E View Figure 3 ) armed distally with 2 strong, denticulate or spinulose elements and 1small, spiniform seta, pulp represented by spinulose lobe. Maxillule ( Figs. 3A View Figure 3 , 10C View Figure 10 ) subrectangular, faintly bilobed, with row of spinules and 1 lateral seta at proximal margin. Outer lobe with row of spinules along outer margin and 4 pinnate setae apically. Inner lobe with 3 pinnate setae. Maxilla ( Figs. 3B View Figure 3 , 8C View Figure 8 ) 2-segmented. Syncoxa almost 2 times longer than wide, with 2 pinnate setae and 1 pinnate spine. Basis with large serrate process, bearing 3 setae (1 pinnate, 1 serrate and 1 naked) and 1 pinnate spine. Maxilliped ( Figs. 3D View Figure 3 , 5C View Figure 5 ) 4-segmented. Syncoxa with 2 pinnate setae along inner margin. Basis with 1 naked and 1 pinnate seta. Endopod 2-segmented; first segment armed with 1 naked seta; second segment bearing 1 naked lateral seta, 3 stout distal spines and 1 naked inner seta.

P1 ( Figs. 4A View Figure 4 , 12C View Figure 12 ) biramous, both rami 3-segmented, and modified for prehension. Coxa and basis fused forming protopod with naked seta on outer corner near exopod insertion; large blade-like element on inner corner, with rounded projection along the outer margin, concentrically lines and acute apex. Exp- 1 with outer seta. Exp-2 with 1 small seta. Exp-3 with 3 outer setae (proximal and distal ones reduced), 2 apical naked setae and 2 inner pinnate setae.

Enp-1 with 1 stout curved process with adhesive areas along the distal margin (marked with square in Fig. 4A View Figure 4 ). Enp-2 with a long seta (marked with asterisk in Fig. 4A View Figure 4 ). Enp-3 elongated, irregular segment ending in a lobe armed with 1 seta and 2 sucking discs; proximal sucking disc 1.5 larger than distal one. P2–P4 ( Fig. 4B–D View Figure 4 ) biramous, with both rami 3-segmented. Coxae with inner pinnate seta. Basis with pinnate seta on outer distal corner and row of setules along inner margin. Exopod outer spines serrate. Endopod outer apical spines serrate, sucking discs on distal outer edge of enp-1 and proximal and subterminal outer edges of enp-3. Armature formula of P2–P4 as follows (Roman numerals representing spines, Arabic numerals representing setae):

P5 ( Fig. 6B View Figure 6 ) uniramous, 2-segmented and located laterally on somite. Protopod with 1 outer seta; free exopodal segment with characteristic shape as shown in Fig. 6B View Figure 6 , with 3 serrate spines along outer margin and 1 serrate spine apically. P6 ( Fig. 7A View Figure 7 marked with blue square) consisting of 2 setae.

Male: total length 0.49–0.65 mm (N = 15). Body cyclopiform ( Fig. 10A, B View Figure 10 ).

Prosome ( Fig. 10A, B View Figure 10 ) longer than urosome (1.6:1). Maximum width measured at midlength of cephalic shield. First pedigerous somite fused with cephalothorax. Body prosomites with minute integumental pits, sensilla and pores distributed as illustrated in figures. Cephalothorax and 3 free prosomites with posterior borders smooth; somites bearing P2–P3 subequal; somite bearing P4 with distal margin concave medially.

Urosome ( Figs. 7A View Figure 7 , 10A, B View Figure 10 ) 5-segmented, narrower than prosome. Somite bearing P5 ( Figs. 7A View Figure 7 , 10B View Figure 10 ) 2 times wider than long in ventral view and with P5 arising ventrolaterally. Anal somite ( Figs. 7A View Figure 7 , 10B View Figure 10 ) extremely reduced and deeply incised medially. Caudal rami ( Figs. 2C View Figure 2 , 7A View Figure 7 ), shorter than to the female and seta V, 3 times longer than seta IV.

Antenna ( Figs. 7B View Figure 7 , 10C View Figure 10 ) 4-segmented. Coxobasis elongated, with row of spinules along inner margin, with seta on inner distal corner.Endopod 3-segmented; segment 1 with pinnate spine inserted along inner margin; segment 2 with row of denticles, 2 naked setae, 1 pinnate spine and 1 serrate spine; segment 3 with 4 pinnate setae and 2 spines (1 pinnate and 1 serrate). Mandible, maxilla and maxillule as in female. Maxilliped ( Figs. 6C View Figure 6 , 10C View Figure 10 ) strongly modified for prehension. Syncoxa with 2 pinnate setae. Basis with 1 naked seta, unequal denticulate projections and distal half of border curved and with irregular margin. Endopod represented by a strong serrate claw.

P1 ( Figs.6D View Figure 6 , 12D View Figure 12 ) similar to female.Coxa and basis fused with 1 naked seta on outer corner and 1 pinnate seta on inner distal edge. Exp-1 with outer seta. Exp- 2 with 1 small outer seta. Exp-3 with 2 outer setae, 1 serrate spine and 1 pinnate spine apically and 2 pinnate inner spines. Enp-1 with adhesive fringe along distal margin, stout curved process and long pinnate seta on inner distal corner. Enp-2 with a long seta. Enp-3 elongated, irregular segment ending in a lobe armed with 1 seta and 2 sucking discs.

P2–P4 ( Fig. 10B View Figure 10 ) with larger coxae and not so elongated basis when compared with female.Armature formula of P2–P4 as follows (Roman numerals representing spines, Arabic numerals representing setae):

P5 ( Fig. 7A View Figure 7 ) elongated, 7 times longer than wide and almost stright. Exopodal segment elongated with 2 serrate spines and naked seta along outer margin and 1 pinnate spine apically, spine I inserted near spine II, on the distal third of the segment. P6 ( Fig. 7A View Figure 7 ) with 1 pinnate seta.

Etymology. The species name persiaensis is derived from the Latin meaning of or belonging to Persia referring to the provenance of the material.