Periclimenaeus colemani, Bruce, 2014

Bruce, A. J., 2014, Periclimenaeus colemani sp. nov. (Crustacea; Palaemonidae; Pontoniinae) from Heron island, Queensland, Zootaxa 3774 (3), pp. 258-264 : 258-264

publication ID	https://doi.org/ 10.11646/zootaxa.3774.3.2
publication LSID	lsid:zoobank.org:pub:72536021-4C1F-4CF8-A06B-5BB34BD4E16C
DOI	https://doi.org/10.5281/zenodo.5047732
persistent identifier	https://treatment.plazi.org/id/03864A42-8E46-FFD5-FF08-D3CED2E7FE5D
treatment provided by	Felipe
scientific name	Periclimenaeus colemani
status	sp. nov.

Treatment

Periclimenaeus colemani View in CoL sp. nov.

( Figs 1–4 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 )

Material examined. 1 ♀, holotype, Wistari Reef, Heron Island , Queensland, coll. Leigh Owens & Lester J. Thompson, 15 June 1979, NE spur and groove zone, AJB#2956 , QM W29203 .

Diagnosis. —Rostral dentition 3/0, slender, up-curved, carapace without supraorbital spines, tubercles or postorbital carina, first abdominal tergite without anterior dorsal lobe, scaphocerite with distolateral tooth well exceeded by lamella, incisor process of mandible bidentate, first pereiopod fingers spatulate, edges entire, second pereiopod chelae smooth, major dactyl with well developed molar process, cutting edge distally finely denticulate, about 25 denticles, merus and ischium ventrally unarmed, minor second pereiopod dactyl with cutting edge strongly dentate, about 20 teeth, fixed finger dentate, about 18 denticles, third pereiopod with dactylar unguis small, corpus lacking distal accessory tooth, with small acute proximal process, ventral margin of corpus straight, third, fourth and fifth pereiopods similar, with propod and carpus slender, caudal fan normal, telson with small dorsal spines at 0.4 and 0.8 of telson length, exopod of uropod with posterolateral tooth and spine only.

Description. Holotype ♀. Rostrum ( Fig. 1A View FIGURE 1 ) slender, compressed, short, about 0.45 of CL, reaching to end of proximal segment of antennular peduncle, dorsal carina with three similar acute teeth on distal four fifths, sparse interdental setae, ventral carina obsolete, margin convex, unarmed.

Carapace ( Fig. 1B View FIGURE 1 ) smooth, glabrous, slightly compressed, without supraorbital spines or tubercles, with small postorbital “shoulder”, orbit feebly developed, without associated carinae, antennal tooth ( Fig. 1B View FIGURE 1 ) well developed, suborbital, inferior orbital angle obsolete, anterolateral carapace margin produced.

Abdomen without anteromedian dorsal lobe on first segment, pleura of first three segmenta enlarged, broadly rounded, fourth and fifth smaller, sixth 1.1 times length of fifth, fifth 0.55 of telson length, posterolateral tooth and posteroventral tooth well developed.

Telson ( Fig. 1I View FIGURE 1 ) 0.6 of CL, about 2.0 times sixth segment length, twice as long as maximal breadth, lateral margins posteriorly straight, convergent to rounded posterior margin ( Fig. 4H View FIGURE 4 ), 0.33 of maximal width, without median point, two pairs of small subequal dorsal spines at 0.4 and 0.8 of telson length, 0.07of telson length, posterior margin with small lateral spines, subequal to dorsal sine length, robust intermediate spines, 0.14 of telson length, submedian spines of similar length, more slender, non-setulose.

Antennule ( Fig. 1C View FIGURE 1 ) with proximal segment of peduncle ( Fig. 1D View FIGURE 1 ) about 1.6 times longer than central width, medial margin straight, with acute ventral tooth at about 0.5 of length, lateral margin produced, distally concave, with rounded distolateral tooth, stylocerite acute, phylliform, statocyst with granular statolith, intermediate and distal segments short, subcylindrical, subequal, about 0.3 of proximal segment length, upper flagellum biramous, proximal four segments fused, short free ramus with single segment, with twelve groups of aesthetascs, longer free ramus with six segments; lower flagellum short, filiform, with eight segments.

Antenna ( Fig. 1E View FIGURE 1 ) with basicerite unarmed; carpocerite reaching to middle of intermediate segment of antennular peduncle, well exceeding scaphocerite, subcylindrical, about 5.0 times longer than wide; merocerite and ischiocerite without special features; scaphocerite ( Fig. 1F View FIGURE 1 ) normal, subequal to carpocerite length, about 4.0 times longer than distal width, distal lamella rounded, lateral margin straight with robust distolateral tooth at 0.85 of length, 0.12 of lateral margin length, reaching almost to distal margin of lamella.

Eye ( Fig. 1G View FIGURE 1 ) with cornea hemispherical, oblique, diameter about 0.18 of CL, 0.9 of medial stalk length, without visible accessory pigment spot, stalk about 1.2 times longer than deep, subcylindrical, as long as wide.

Mouthparts, right side.

Mandible ( Fig. 2A View FIGURE 2 ) with corpus robust, without palp, molar process ( Fig. 4A View FIGURE 4 ) subcylindrical, truncate distally, fringed peripherally by short slender spinules, with central acute tooth; incisor process ( Fig. 4B View FIGURE 4 ) slender, tapering to two small acute distal teeth, larger tooth lateral, medial tooth bidentate ( Fig. 4C View FIGURE 4 ).

Maxillula ( Fig. 2B View FIGURE 2 ) with palp simple (Fig. 5D), non-setose; upper lacinia lost in dissection; lower lacinia short, stout, distally rounded, with sparse long serrulate spiniform setae.

Maxilla ( Fig. 2C View FIGURE 2 ) with flattened tapering palp, about 2.6 times longer than basal width, non-setose, basal endite simple, 2.2 times longer than wide, with eleven slender terminal setae; scaphognathite normal, narrow, about 3.0 times longer than central width, anterior lobe 1.4 times longer than wide, medial margin concave, posterior lobe 2.4 times longer than basal width

First maxilliped ( Fig. 2D View FIGURE 2 ) with flattened palp without seta, basal and coxal endites fully fused, distally rounded, medial margin straight with numerous slender setae, decreasing in size proximally, exopod normal, flagellum slender, with four plumose distal setae, caridean lobe large, about 2.0 times longer than central width, epipod well developed, rounded, feebly bilobed.

Second maxilliped ( Fig. 2E View FIGURE 2 ) with normal endopod, dactylar segment narrow, 3.0 times longer than broad, with numerous long slender serrulate marginal spines, propodal segment antero-medially rounded, not produced, with several long slender marginal spines, carpus, merus and ischiobasis without special features, exopod with slender flagellum with four long terminal setae, coxa medially produced, rounded, with oval epipod laterally without podobranch.

Third maxilliped ( Fig. 2F View FIGURE 2 ) with ischiomerus and basis almost fully fused, combined segment 2.0 times longer than basal width, tapering distally, sparsely setose medially, carpus robust, subcylindrical, 2.0 times longer than width, with several spiniform setae medially, terminal segment 0.8 of carpal length, 3.0 times longer than proximal width, tapering distally, with numerous spiniform setae medially, exopod with slender flagellum with four long plumose terminal setae, coxa robust, medial margin straight, non-setose, lateral margin with well developed rounded lateral plate, without arthrobranch.

Thoracic sternite s narrow, unarmed.

First pereiopod ( Fig. 3A View FIGURE 3 ) robust short, merus reaching to end of antennular peduncle, chela ( Fig. 3B View FIGURE 3 ) about 0.28 of CL, palm subcylindrical, slightly compressed, 1.5 times longer than deep, fingers subequal to palm length, normal, subspatulate, cutting edges entire, tips rounded with two small terminal teeth ( Fig. 4D View FIGURE 4 ); carpo-propodal cleaning setae poorly developed; carpus 1.9 times chela length, 4.6 times longer than distal width, tapering proximally; merus about 1.8 times chela length, 3.4 times longer than maximal width, tapering slightly distally; ischium 0.6 of chela length; basis without special features; coxa normal, without ventral process.

Second pereiopods unequal, dissimilar.

Major second pereiopod ( Fig. 3C View FIGURE 3 ) with chela about 2.0 times CL, palm subcylindrical, slightly swollen centrally, compressed, about 1.7 times longer than depth, smooth, glabrous; fingers ( Fig. 4D View FIGURE 4 ) subequal, 0.45 of palm length, dactyl ( Fig. 3E View FIGURE 3 ) about 2.2 times as long as maximal depth, compressed, dorsal margin strongly convex, tip acute (lost in dissection), cutting edge with large molar process proximally, distally feebly concave ( Fig. 4E View FIGURE 4 ), with about 20 small acute teeth over distal three-fourths, increasing slightly in size distally, proximally minute; fixed finger about 1.6 times longer than proximal depth, cutting edge with deep fossa proximally, dorsal margin with acute process, ventral margin with rounded glabrous process, tip acute, strongly hooked, distal cutting edge entire; carpus about 0.33 of palm length, 1.3 times longer than maximal depth, distally excavate, tapering proximally, unarmed; merus robust, 1.8 times longer than central depth, slightly swollen centrally, ventral margin unarmed; ischium 1.2 times meral length, twice as long as distal width, tapering proximally, unarmed; basis and coxa without special features.

Minor second pereiopod ( Fig. 3F View FIGURE 3 ) with chela about 1.5 of CL, 0.6 of major chela length, palm sub-cylindrical, slightly swollen proximally, compressed, about 2.6 times longer than depth, smooth, glabrous; fingers ( Fig. 3 View FIGURE 3 GH) about 0.35 of palm length, dactyl ( Fig. 3G View FIGURE 3 ), about 2.8 times longer than maximal depth, not exceeding fixed finger, compressed, dorsal margin strongly convex, tip with small acute tooth continuous with sinuous cutting edge ( Fig. 3H View FIGURE 3 ), distally concave, proximally convex, with series of well developed teeth, about 25 acute teeth, large distally, proximally minute, along sinuous margin; fixed finger about twice as long as proximal depth, distal cutting edge feebly longitudinally grooved, dorsal margin unarmed, ventral margin with distal, three quarters denticulate, teeth small acute, increasing in size distally, about 18, proximal fourth with small acute tooth, tip acute, small; proximal segments as for major pereiopod but smaller.

Third pereiopod (Fig. IC) robust, dactyl ( Fig. 4E View FIGURE 4 ) about 0.18 of propod length, compressed, unguis very short, robust, curved, 1.8 times longer than basal width, 0.14 of dorsal corpus length, without ornamentation, corpus with dorsal margin slightly convex, about 7.0 times length of unguis, ventrally without distal accessory tooth, mainly straight, slightly convex distally, entire, proximal portion with short robust angular tooth, with long sensory setae distolaterally; propod ( Fig. 3J View FIGURE 3 ) about 0.33 of CL, robust, compressed, 3.4 times longer than proximal depth, tapering slightly distally, with stout distoventral spine laterally, shorter, slender spine medially ( Fig. 3K View FIGURE 3 ), without ventral spines, sparsely setose; carpus similar to propod, more swollen, compressed, 2.5 times longer than central width, 1.3 times longer than propod length, unarmed; merus robust, 1.4 times propod length, compressed, 2.2 times longer than central width, unarmed; ischium 0.8 of propod length, 2.4 times longer than distal width, tapering strongly proximally, unarmed; basis and coxa stout, without special features.

Fourth pereiopod similar to third, shorter, more slender, dactyl similar, propod 1.1 times third propod length, 0.31 of POCL, 5.0 times longer than proximal width

Fifth pereiopod similar fourth, shorter, more slender, dactyl similar, propod 0.9 of third propod length, 0.4 of POCL, 0.2 times longer than proximal width, with numerous distoventral spiniform setae, without spines.

Pleopods without special features, second pleopod removed ( Fig. 4F View FIGURE 4 ), protopod ( Fig. 4G View FIGURE 4 ) medially with three short ovigerous setae proximally, two distally.

Uropods ( Fig. 1I View FIGURE 1 ) about as long as telson tip, protopodite laterally unarmed; exopod about twice as long as central width, lateral margin feebly convex with small acute distolateral tooth with 3.0 times larger mobile spine medially ( Fig. 4I View FIGURE 4 ); endopod of similar length, 2.4 times longer than central width.

Measurements, (mms). Holotype female—post-orbital carapace length, 2.4; carapace and rostrum, 3.2; total body length (approx.), 10.4; major second pereiopod chela length, 4.4; minor second pereiopod chela length, 2.8.

Host. Associated with a didemnid host, Leptoclinides sp. (Ascidiacea) , det. R.H. Millar, 13 July 1979.

Colouration (from field notes, AJB). Generally translucent, body and appendages with covered red and white spots, the red generally larger than the white, sparse white spots on first pereiopod chela and carpus, with white spots only on caudal fan.

Etymology. Named in honour of Neville Coleman, OAM, (1938— 5 May 2012), underwater photographer par excellance, who established the Australian Marine Photographic Index and always endeavoured to provide taxonomists with back-up samples of his subjects.

Systematic position. A member of the Periclimenaeus Group 7 noted by Bruce (2013) with the third pereiopod dactyl lacking a distal accessory tooth on the corpus, with some proximal ornamentation only. Similar to P. zarenkovi Duris, 1990 , known only from the male holotype specimen from the Maldive Islands. The two species share the following characters: without post-orbital carina, major second pereiopod dactyl distally denticulate, third pereiopod dactyl with slender acute proximal tooth, without mobile distolateral spine on third pereiopod carpus, and dorsal telson spines small. A key to the species of this group was provided by Bruce (2014) and the last couplets of this may be modified to include P. colemani —

11. Third pereiopod dactyl with unguis well developed, 0.5 of dorsal corpus length, dorsal telson spines at about 0.3 and 0.6 of telson length, minor second pereiopod with cutting edge of dactyl near straight with 40 uniform small teeth, fixed finger cutting edge entire, rostral dentition 5/0....................................................... P. zarenkovi Ďuriš, 1990

- Third pereiopod, dactyl with unguis small, 0.02 of dorsal corpus length, dorsal telson spines at about 0.4 and 0.85 of telson length, minor second pereiopod with cutting edge of dactyl sinuous with about 20 small teeth of decreasing size proximally, fixed finger cutting edge denticulate, rostral dentition 3/0...................................... P. colemani sp. nov.

Remarks. Periclimenaeus calmani is notable particularly for the very small unguis on the ambulatory pereiopods and the small details of the fingers of the second pereiopods which will distinguish it from all other species of this genus.