Synapseudes caleyi Stępień & Błażewicz, 2018

Heard, Richard W., Stępień, Anna, Drumm, David T., Błażewicz, Magdalena & Anderson, Gary, 2018, Systematic and taxonomic observations on the subfamily Synapseudinae Guţu, 1972 and related metapseudid taxa (Crustacea: Tanaidacea: Apseudomorpha), with the erection of a new genus and descriptions of three new species, Zootaxa 4370 (4), pp. 301-344 : 320-326

Synapseudes caleyi Stępień & Błażewicz , n. sp.

Figures 9–12

Material examined. Holotype—female (W53969), NIN 12A, 21.54106°S, 113.56010°E, Ningaloo Reef, Tantabiddy, reef slope, coral heads, depth 12–14 m, coll. M. Błażewicz (MB) & C. Hass ( CH) . Allotype: (W53970), NIN 12A, 21.54106°S, 113.56010°E, Ningaloo Reef , Tantabiddy, reef slope, coral heads, depth 12–14 m, coll. MB & CH .

Paratypes— ten ♀♀, five ♂♂ (W53971), NIN 7A, 21.54724°S, 113.57105°E, Ningaloo Reef, S Tantabiddy, Ramp, lagoon, patch reef, dead coral heads, depth 3 m, coll. N. L. Bruce (NLB) & MB; one ♀, one ♂ (W53972), NIN 7B, small rubble on sand, depth 2.5–3.5 m; two ♀♀, one ♂ (W53973), NIN 0 0 8, 21.55109°S, 113.57612°E, Ningaloo Reef, S pass, lagoon, parties bommies, depth 3–5 m, coll. NLB & MB; two ♀♀, one ♂ (W53974), NIN 8A, large pieces of rubble, depth 3 m; two ♀♀ (W53975), NIN 8D, half-head of Acropora sp. on sand, depth 3 m; two ♀♀ (W53976), NIN 8E, dead coral head, depth 4 m; one ♀ (W53977), NIN 8I, flat piece dead Acropora, depth 3 m; one ♀ (W53978), NIN 9, 21.51399°S, 114.00152°E, Ningaloo Reef, N pass, edge lagoon, large bommie with gullies, depth 4–5 m, coll. MB & CH ; twelve ♀, two ♂♂, four juveniles (W53979), NIN 9B, dead Acropora, depth 4 m; six ♀♀, three ♂♂ (W53980), NIN 10B, 21.54614°S, 113.55702°E, Ningaloo Reef, S Tantabiddy, reef front, high exposure, spur and groove, rubble on top of spur, depth 9–14.7 m, coll. NLB & MB; 15 ♀♀, six ♂♂ (W53981), NIN 10C, coral heads spur sides, depth 9–14.7 m; five ♀♀, one ♂ (W53982), NIN 12A, 21.54106°S, 113.56010°E, Ningaloo Reef, N Tantabiddy, reef front, reef slope, coral heads, depth 12–14 m, coll. MB & CH ; five ♀♀, one ♂ (W53983), NIN 13B, 21.51148°S, 114.00204°E, Ningaloo Reef, N Tantabiddy, reef front, out from reef edge, Acropora head on sand, depth 10 m, coll. MB & NLB; 1♀♀ (W53984), NIN 14A, 21.54505°S, 113.57963°E, Ningaloo Reef, S Tantabiddy, reef front, coarse sand, depth 10 m, coll. NLB & MB; five ♀♀ s, three ♂♂ (W53985) NIN 14C, small-medium rubble in gully, depth 10 m; eight ♀♀, four ♂♂ (W53986), NIN 14E, fragment of Pocillopora sp., depth 10–14 m; one ♀, one ♂ (W53987), NIN 14F, rubble and sand; one ♀, one ♂ (W53988), NIN 15, 21.52153°S, 113.57948°E, Ningaloo Reef, N Tantabiddy pass, reef front, sand, depth 23–24 m, coll. MB & CH ; three ♀♀, two ♂♂ (W53989), NIN 17A, 21.55419°S, 113.55176°E, Ningaloo Reef, N Tantabiddy pass, reef front, dead Acropora heads, depth 13–15 m, coll. NLB & MB; two ♀♀, two ♂♂ (W53990), NR 09-52A, 22.63555°S, 113.63126°E, Ningaloo Reef, Point Cloates, lagoon, back reef, patch of live and dead Acropora, depth 2.5–3 m, coll. NLB & J. Fromont (JF); 18♀♀, seven ♂♂ (W53991), NR 09-64A, 22.51728°S, 113.66323°E, Ningaloo Reef, Point Cloates, outer fore reef, dead coral heads on wreck and bommie, depth 8–10 m, coll. NLB & L. Hughes (LH); two ♀♀ (W53992), NR 09-64C, finger rubble on sand, depth 9 m; nine ♀♀, four ♂♂ (W53993), NR 09-70A, 22.60826°S, 113.62486°E, Ningaloo Reef, Point Cloates, outer fore reef, dead Acropora heads, depth 15 m, coll. NLB & LH; two ♀♀ (W53994), NR 09-80A, 22.35633°S, 113.37905°E, Ningaloo Reef, Point Cloates, N Norwegian Channel, outer fore reef, dead coral on spur, depth 18–20 m, coll. NLB & LH; two ♀♀ (W53995), NR 09-85A, 22.45451°S, 113.38998°E, Ningaloo Reef, Point Cloates, Black Rock, flat coral pavement with 3 m ledge to sand, depth 16–17 m, coll. NLB & LH; six ♀♀ (W53996), NR 09-85B, medium rubble, depth 21–22 m; one ♀ (W53997), NR 09-85C, sand at base of ledge, depth 19 m; one ♀ (W53998), NR 09-85G, fine sediment; six ♀♀ (W53999), NR 09-92A, 22.46045°S, 113.38372°E, Ningaloo Reef , Point Cloates, S Black Rock, deep reef slope, large rubble, depth 26 m, coll. LH & M. Eckin (ME).

Diagnosis. Inner antennular inner flagellum with one article. Antennal flagellum with two articles, terminating in long simple seta and two minute subdistal accessory setae. Pereopod-1 propodus having ventral margin with four spiniform setae; pereopods 2–3 propodus having ventral margin with three spiniform setae. Pleonites 1–3 partially fused, but completely delineated. Uropodal endopod with three articles. Terminal adult male strongly sexually dimorphic, heterochelate with major cheliped greatly enlarged, massive.

Description of adult female. Body ( Fig. 9 A, B ). Length 1.4 mm, 4.6 times longer than broad.

Cephalothorax ( Fig. 9A, B ). 26% of total body length; carapace lateral margin with seta at mid-length; rostrum flat, with serrate margin; eyes with dark pigment; small setae present under the eyes lobe.

Pereon ( Fig. 9A, B ). 60% of total body length, pereonites rectangular with 1, 4 and 5 similar in length, length about 0.37 times width; length/width of pereonites 2, 3 and 6 equal to 0.44, 0.52, and 0.34, respectively; all pereonites with two simple setae on anterolateral margin; pereonites 4–6 with simple seta on posterolateral margin.

Pleon ( Fig. 9A, B ). About 15% of total body length, with vestiges of three free pleonites and pleotelson; all indications of pleonites similar in length, pleonite-1 with two simple setae, pleonite-3 with one simple seta. Pleotelson length 1.6 times that of all pleonites combined, with eight setae on dorsal surface.

Antennule ( Fig. 10A ). Peduncle with four articles; article-1 robust, length about 1.7 times as long broad with four broom setae and three simple along outer margin inner margin with row of seven subacute spines and three simple setae; article-2 about 0.8 times longer than article-1, with three setae on outer distal corner, and apophysis and two simple setae on inner distal corner; article-3 shorter and narrower than article-2, length about 0.9 times width, with simple seta and broom setae distally; common article with one distal seta. Inner flagellum consisting of single article with three distal setae. Outer flagellum consisting of three articles, with aesthetasc on article-1 and 2; article-3 terminating in three long simple setae.

Antenna ( Fig. 10B ). Peduncle with four articles; article-1 with bulge, inner margin row of six small subacute spines; article-2 having margin with four denticles and one distal simple seta; article-3 about as long as article-2 and having inner margin with two tubercles; article-4 about twice as long as article-3, and having four broom setae on distal margin. Flagellum with two articles, article-2 minute with long terminal seta and two minute subdistal accessory setae.

Mandible. Right mandible ( Fig. 10C ): Incisor simple, blunt; setiferous lobe with reduced bifurcate lacinia mobilis and three setulate setae; molar ( Fig. 10C ) wide, strongly calcified and serrate distally, with one setulate seta. Left mandible ( Fig. 10D ) incisor simple, bearing blunt distal teeth and two small lateral apophyses; lacinia mobilis with five blunt “teeth, setiferous lobe with three setulate setae; molar with serrate margin and small distal setulate seta. Palp of both right and left mandibles with three articles; articles 1–2 subequal and asetose; article-3 small, about 0.3 times the length of article-2.

Maxillule. Outer endite ( Fig. 10E ) with seven distal spines, outer margin with small cluster of fine setae, inner margin with two small shallow apophyses; inner endite wide with four setulate distal setae; outer margin setose.

Maxilla ( Fig. 10F ). With two spines on outer margin; moveable endite outer lobe of with three distal and two subdistal setae; inner lobe of moveable endite with three distal setae; outer lobe of fixed endite with four simple setae, two spiniform distally trifurcate setae and setulose seta subdistally; inner lobe of fixed endite with row of nine distal setae.

Maxilliped ( Fig. 10G ). Basis asetose, narrow. Palp having article-1 about 0.6 times as long as wide with simple seta on inner distal margin, and robust, long spine on outer distal margin; article-2 length about 0.7 times width with outer margin having eight inner setae, long seta, and two apophyses; article-3 with inner margin having six distal and two short subdistal setae; article-4 with length about 1.3 times width with five basally swollen distally setulate setae. Endite ( Fig. 10H ) bearing four setulate setae and two short blunt spiniform setae on inner distal margin; inner margin with row of basally swollen setulate setae and four coupling-hooks

Epignath ( Fig. 10I ). Narrow, curved, terminating in long, strong seta.

Cheliped ( Fig. 10J ). Basis about 1.3 times longer than width, ventral margin with two setae and three small distal apophyses. Merus subtriangular, with four setae distally. Carpus about 2.2 times longer than width and bearing three ventral setae and one distodorsal seta. Propodus about 0.7 times as long as carpus, inner face of palm with two pectinate setae adjacent to dactylus, one simple seta and apophysis near insertion of dactylus; fixed finger about half as long as propodus, with three long setae and short ventral seta, and with four setae on inner grasping edge. Dactylus with two small setae on inner margin.

Pereopod-1 ( Fig. 11A ). Basis about 2.8 times longer than width, ventral margin with three setae and two spiniform apophyses, dorsal margin with two broom setae. Ischium about one fifth as long as wide, ventral margin with two (one small) setae. Merus about 1.6 times longer than wide; ventral margin with three simple setae and three spiniform seta; dorsal margin having stout spiniform seta and simple seta distally. Carpus about three fifths as long as merus; ventral margin with two spiniform setae and small distal simple seta; dorsal margin distally with stout spiniform seta and three simple setae. Propodus about 1.6 times as long as carpus; ventral margin with four stout spiniform setae; distal inner margin with short bipectinate seta; dorsal margin with one broom seta medially, one spiniform setae and long stiff simple seta distally; one stout spiniform seta subdistally. Dactylus about two fifths as long as propodus, with one minute ventral and two minute dorsal setae; unguis length about two fifths as long as dactylus.

Pereopod-2 ( Fig. 11B ). Basis three times as long as wide, ventral margin with one small simple seta, one distoventral spine, and three spiniform apophyses; dorsally with and two broom setae on margin. Ischium 2.6 times as long as wide, with distoventral seta. Merus 1.4 times as long as wide; inner face having ventral margin with three setae; dorsal margin distally with one small medial seta subdistally. Carpus half as long as merus, inner face with five spiniform setae and two simple setae along ventral and distal margin. Propodus 1.7 times as long as carpus; ventral margin with three spiniform setae, one short bipectinate seta distally on inner face; dorsomedial margin with one broom seta, two stout spiniform setae; inner face with stout spiniform seta subdistally. Dactylus 0.7 times as long as propodus, with two-minute ventral setae and one minute dorsal seta; unguis half as long as dactylus.

Pereopod-3 ( Fig. 11C ). As in pereopod-2, but with basis having two dorsal spiniform apophyses.

Pereopod-4 ( Fig. 11D ). Basis 3.1 times as long as wide; ventral margin distally with one simple seta; dorsal margin with one broom seta. Ischium about 0.6 times as long as wide, with one ventral seta; merus twice as long as wide, with two setae and two spine subdistally. Carpus 0.6 times as long merus, with five robust spines and one seta subdistally and distally. Propodus subequal to merus; ventral margin with three spiniform setae and distal pectinate on inner face; dorsal margin with broom seta and distally with three bipectinate setae. Dactylus half as long as propodus, with two ventral and one dorsal minute setae; unguis 0.8 times as long as dactylus.

Pereopod-5 ( Fig. 11E ). Basis 3.3 times as long as wide, ventral margin with two setae, dorsal margin with two dorsal broom setae. Ischium 0.3 times as long as wide, with ventral seta distally. Merus 1.2 times as longer than wide, ventral margin with two distal setae; dorsal margin with one distal seta. Carpus 0.8 times as long as merus, with two spines and one distoventral seta, and one spiniform seta and one distodorsal seta. Propodus twice as long as merus; ventral margin with subproximal and subdistal spiniform seta; dorsal margin with broom seta, and two pectinate setae and one spiniform seta distally. Dactylus about half as long as propodus, with two minute ventral setae and one minute dorsal seta; unguis about two thirds as long as dactylus.

Pereopod-6 ( Fig. 11F ). Similar to pereopod-5, but carpus with two setae and one spiniform seta distoventrally, and lacking distodorsal spiniform seta.

Uropod ( Fig. 11G ). Basal article about twice as long as wide, with two distoventral setae, apophysis on inner distal margin. Exopod biarticulate, distal article with two setae. Endopod with three articles: article-2 with distal broom and simple seta, terminal article-3 with three long and two short simple setae.

Adult male ( Fig. 12A–C ). Body similar to female, but cheliped sexually dimorphic, heterochelate. Minor left cheliped as in female ( Fig. 12B ). Right cheliped greatly in enlarged and massive ( Fig. 12A, C ) with length of basis about same as width, dorsally with distal serration and ventrally with penicillate seta. Merus triangular, with ventral, subacute, spiniform apophysis and simple seta. Carpus about as long as wide, with denticulate ventral margin having distodorsal seta and three ventral setae. Propodus, excluding fixed finger, as long as wide, with four simple setae in gap between fixed finger and dactylus; fixed finger ventral margin with three setae, inner (incisive) margin with seven marginal or submarginal setae, tip with three small denticles. Dactylus with inner margin with three weakly developed denticles and four minute setae with tip nail) weakly bidentate.

Etymology. This species is named in honor of Julian Caley, the leader of the CReefs Australian Node.

Distribution. Ningaloo Reef, Western Australia.

Remarks. Synapseudes caleyi n. sp. and six other members of the genus (i.e., S. australianus , S. hansmuelleri , S. minimus , S. rectifrons , S. rudis and S. violaceus ) are distinguished as follows: (1) the peduncular article-2 of the antennule has distal spiniform apophyses, (2) a biarticulate antennal flagellum terminates in a long seta, (3) the ventral margin of the propodus of pereopod-1 bears four spiniform setae, (4) the first three pleonites are completely delineated, and (5) the uropodal endopod is composed of three articles.

Synapseudes caleyi differs from the other six species within this group by having the inner antennular flagellum composed of a single article instead of two. The only other members of the genus to have a reduced inner antennular flagellum are the atypical species S. aflagellatus , S. mediterraneus and S. shiinoi . To further differentiate S. caleyi from the other members of the genus refer to Table 3 and the Key presented herein.

Figures

FIGURE 9. Synapseudes caleyi n. sp. Femaleholotype. A, body dorsal view; B, body lateral view.Scale line = 1mm.

FIGURE10.Synapseudes caleyi n.sp.Female holotype. A, antennule; B antenna;C, rightmandible, incisorand molar; D, left mandible, entire; E, maxillule, outer and inner endite; F, maxilla; G, maxilliped, basis and palp; H, maxilliped, endite; I, epignath; J, right cheliped, inner aspect. Scale line = 0.1mm.

FIGURE 11. Synapseudes caleyi n. sp. Female holotype. A, pereopod 1; B pereopod 2; C, pereopod 3; D pereopod 4; E, pereopod 5; F pereopod 6; G, uropod. Scale line = 0.1 mm.

FIGURE 12. Synapseudes caleyi n. sp. Male allotype. A, habitus, lateral aspect; B, minor left cheliped; C, major right cheliped, lateral aspect.Scale line = 1 mm.