Periclimenes sarkanae, Bruce, 2007

Bruce, A. J., 2007, Periclimenes sarkanae sp. nov. a new pontoniine shrimp from Moreton Bay, Queensland (Crustacea: Decapoda: Palaemonidae), Zootaxa 1393 (1), pp. 61-68 : 61-68

publication ID	https://doi.org/ 10.11646/zootaxa.1393.7
publication LSID	lsid:zoobank.org:pub:E444A6C4-4023-44AC-82BA-73E63677D1F3
persistent identifier	https://treatment.plazi.org/id/F1630E59-FFFA-270F-6BA8-B3F36DBDFADE
treatment provided by	Felipe
scientific name	Periclimenes sarkanae
status	sp. nov.

Treatment

Periclimenes sarkanae View in CoL sp. nov.

( Figs. 1 –5 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 )

Diagnosis: A species of Periclimenes with a convex transverse plate on the fourth thoracic sternite, with acute submedian processes separated by a subquadrate notch.

Material examined: ♀ holotype, QM W23963 ; ♂ allotype (dissected), QM W28223 ; 3 ♀ paratypes, QM W28224 , Fisherman Island , near mouth of Brisbane River, Moreton Bay, 27°22’S, 153°10’E, 0.2–0.5 m, 2 & 4 June 1998, netted, coll. P. Davie & J.W. Short. GoogleMaps

Description: Body ( Fig. 1 View FIGURE 1 ) subcylindrical, smooth, glabrous.

Rostrum ( Fig. 2 View FIGURE 2 AB) slender, straight, horizontal, or very slightly upturned, subequal to CL or slightly longer, reaching to near or beyond distal end of antennular peduncle, dorsal carina well developed, dorsal margin feebly convex with 89 acute teeth, size diminishing distally, first tooth articulated with carapace, interdental spaces anterior to second tooth with short plumose setae, lateral carinae obsolete, ventral carina obsolete, margin feebly convex, proximally with median plumose setae, with 23 small acute teeth on distal 0.4 of length.

Carapace with articulated epigastric spine ( Fig. 5A View FIGURE 5 ) at 0.25 of CL, orbit ( Fig. 2C View FIGURE 2 ) feebly developed, inferior orbital angle ( Fig. 2 View FIGURE 2 AD), produced, blunt, with inner flange medially ( Fig. 5A View FIGURE 5 ), antennal spine well developed, marginal, hepatic spine of similar size, at lower level, well anterior to level of epigastric spine, anterolateral branchiostegite not produced, bluntly angular, ventral margin minutely setose.

Abdomen with third tergite not posteriorly produced, minutely denticulate ( Fig. 5H View FIGURE 5 ), sixth segment about 0.75 of CL, 2.1 times fifth segment length, 2.0 times longer than deep, posterolateral angle acute, posteroventral angle feebly produced, ventrally setose, pleura all rounded, with numerous plumose marginal setae.

Telson ( Fig. 2J View FIGURE 2 ) about 0.9 of CL, 1.2 times sixth segment length, about 4.0 times longer than anterior width, lateral margins straight, converging, with two pairs of small dorsal spines, about 0.025 of telson length, at about 0.5 and 0.7 of telson length, posterior margin about 0.33 of anterior margin width, bluntly angular, with small acute median process, with three pairs of posterior spines ( Fig. 2K View FIGURE 2 ), lateral spines small, subequal to dorsal spines, intermediate spines well developed, robust, about 0.18 of telson length, submedian spines shorter, 0. 45 of intermediate spine length, setulose.

Antennule ( Fig. 2E View FIGURE 2 ) of normal form, proximal segment ( Fig. 2F View FIGURE 2 ) about 2.0 times longer than wide, medial margin with numerous short spiniform setae, anterolateral margin ( Fig. 5C View FIGURE 5 ) angularly produced with well developed plumose marginal setae, distolateral angle with well developed acute tooth, slightly exceeding medial angle, with plumose marginal setae proximally, lateral margin feebly convex, stylocerite distally acute, reaching to about half segment length, dorsomedial margin with single long plumose seta, ventromedial margin with small acute tooth at about 0.5 of length, statocyst normal with large circular statolith, intermediate segment about 0.33 of proximal segment length, about 1.8 times longer than broad, medially and laterally setose, distal segment subequal to intermediate segment length, flagella slender, upper flagellum biramous, rami with proximal 8 segments fused, shorter free ramus with 8 segments, with about 25 groups of aesthetascs distally, longer ramus filiform, lower flagellum also filiform.

Antenna ( Fig. 2G View FIGURE 2 ) of normal form, basicerite with strong acute distolateral tooth, carpocerite reaching to about 0.33 of scaphocerite length, subcylindrical, about 3.0 times longer than wide, flagellum well developed, scaphocerite ( Fig. 2H View FIGURE 2 ) well developed, exceeding antennular peduncle, about 3.4 times longer than broad, distal margin rounded, lateral margin with acute distal tooth at 0.8 of scaphocerite length, about 0.12 of lateral margin length, well exceeded by lamella.

Eye ( Fig. 2I View FIGURE 2 ) with globular cornea, diameter about 0.2 of CL, with dorsal accessory pigment spot, stalk about 1.5 times longer than wide, slightly tapering distally, peduncle without articular carina laterally.

Ophthalmic somite without béc ocellaire. Epistome unarmed.

Mandible ( Fig. 3A View FIGURE 3 ) with corpus robust, without palp; incisor process ( Fig. 5F View FIGURE 5 ) normal, obliquely truncate distally with four acute teeth, largest tooth laterally, central pair smallest; molar process ( Fig. 5 View FIGURE 5 DE) subcylindrical, expanding slightly distally, with four well developed blunt teeth and small bands of short simple setae.

Maxillula ( Fig. 3B View FIGURE 3 ) with feebly bilobed palp, lower lobe with small ventral tubercle bearing short simple seta, upper lacinia ( Fig. 5G View FIGURE 5 ) broadest centrally, distal margin truncate with double row of 13 short simple spines and numerous simple spiniform setae, lower lacinia tapering distally with numerous slender spines and simple spiniform setae

Maxilla ( Fig. 3C View FIGURE 3 ) with slender tapering distally acute palp, with four short plumose setae proxomolaterally, basal endite deeply bilobed, distal lobe slightly larger than proximal, each with about 12 slender simple setae, coxal endite obsolete, medial margin feebly convex, nonsetose; scaphognathite well developed, about 2.3 times longer than wide, posterior lobe small, about 0.22 of scaphognathite length, anterior lobe about 0.5 of length, medial margin feebly emarginate.

First maxilliped ( Fig. 3D View FIGURE 3 ) with slender, tapering, distally acute nonsetose palp, about 4.0 times longer than basal width, basal endite broadly rounded, medial margin, with numerous long feebly setulose setae, exopod well developed, flagellum with 4 plumose setae terminally, caridean lobe long, narrow, coxal endite small, feebly convex, sparsely setose, with one long sparsely plumose seta distally, epipod rounded triangular.

Second maxilliped ( Fig. 3E View FIGURE 3 ) of normal form, dactylar segment about 3.2 times longer than width, with numerous robust coarsely denticulate marginal spines and shorter spiniform setae, propodal segment broadly rounded distally, feebly produced distomedially, distomedial angle with several slender simple spines, ventromedial margin with numerous long slender simple spines, carpus, merus and ischiomerus without special features, exopod flagellum normal, with 4 plumose terminal setae, coxa medially rounded, sparsely setose, with small suboval epipod laterally, without podobranch.

Third maxilliped ( Fig. 3F View FIGURE 3 ) with endopod slender, reaching to about middle of carpocerite, ischiomerus and basis fully fused, combined segment bowed, about 7.0 times longer than central width, ischiomeral portion uniform, lateral margin sparsely setose, distolateral angle with single small spinule, medial margin with numerous slender simple setae, basal region rounded, sparsely setose, penultimate segment about 0.7 of antepenultimate segment length, uniform, 6.5 times longer than wide, sparsely setose laterally, with 6 pairs of simple spiniform setae medially, of increasing length distally, terminal segment about half length of antepenultimate segment, about 0.5 times longer than basal width, with 5 groups of shorter denticulate spiniform setae medially, terminally bluntly rounded, without terminal spines; coxa feebly medially produced, with small rounded lateral plate, without arthrobranch.

Thoracic segments with five pairs of pleurobranchs; sternites broad, fourth sternite ( Fig. 5I View FIGURE 5 ) without slen der median process, with broad transverse plate projecting anteroventrally, outer margin convex, with two strong acute submedian teeth, separated by quadrate notch; fifth sternite with lower transverse carinae laterally, acutely pointed medially, separated by small notch; posterior sternites unarmed.

First pereiopod ( Fig. 4A View FIGURE 4 ) slender, extending to about end of antennular peduncle, chela ( Fig. 4B View FIGURE 4 ) with palm oval in section, slightly tapering distally, about 2.4 times longer than deep, with 5 transverse rows of short curved denticulate spinules proximoventrally, fingers slender, sparsely setose, about 0.85 of palm length, dactylus 5.0 times longer than proximal depth, with robust hooked terminal spine ( Fig. 5J View FIGURE 5 ), cutting edge laminar over distal third, entire, proximally unarmed, fixed finger similar; carpus 1.15 times longer than chela, 5.5 times longer than distal width, tapering proximally; merus 1.1 times longer than carpus, slender, 8.0 times longer than central width; ischium compressed, 0.5 of merus length, sparsely setose ventrally, setae spiniform; basis about 0.55 of ischial length, similarly setose ventrally, coxa ( Fig. 4C View FIGURE 4 ) more robust, with subacute distoventral process ( Fig. 4D View FIGURE 4 ) with 34 slender spiniform preterminal setae.

Second pereiopods ( Fig. 4E View FIGURE 4 ) normal, slightly unequal, similar, exceeding antennular peduncle by length of chela; major chela ( Fig. 4F View FIGURE 4 ) about subequal to CL, palm smooth, oval in section, 3.0 times longer than deep, slightly swollen centrally, fingers ( Fig. 4G View FIGURE 4 ) slender, about 0.9 of palm length, sparsely setose, dactylus about 6.5 times longer than proximal depth, compressed, with small robust hooked terminal spine, cutting edge laminar over almost whole length, entire, without dentition, fixed finger similar, with feeble diastema proximally; minor chela similar, about 0.85 of major chela length, fingers subequal to palm length; carpus subequal to palm length, 5.5 times longer than distal width, tapering proximally, unarmed; merus about 1.2 times carpal length, uniform, about 9.0 times longer than central width, unarmed; ischium slender, 1.15 times meral, length, 10.0 times longer than distal width, tapering proximally, unarmed; basis and coxa short, without special features.

Ambulatory pereiopods slender, third pereiopod ( Fig. 4H View FIGURE 4 ) reaching to about end of scaphocerite; dactylus ( Fig. 4J View FIGURE 4 ) slender, curved, about 0.25 of propod length, unguis feebly demarkated, about 5.0 times longer than basal width, 0.6 of corpus length, corpus compressed, about 3.3.times longer than central width, scarcely tapering distally, ventral margin concave with long slender distal accessory tooth, about 0.6 of unguis length; propod ( Fig. 4I View FIGURE 4 ) about 0.55 of CL, about 14.0 times longer than wide, uniform, sparsely setose, with two similar long distoventral spines, about 0.3 of dactyl length, two similar pairs of spines on distal fifth of ventral propod length, with single shorter spine at half length; carpus 0.5 of propod length, merus subequal to propod; ischium subequal to carpal length, basis and coxa short, without special features. Fourth and fifth pereiopods similar to third, fifth propod about 0.68 of CL, with additional denticulate setae distolaterally.

Pleopods of normal form; basipodites with densely setose ventral carina. Male first pleopod ( Fig. 5K View FIGURE 5 ) with basipodite 4.2 times longer than width; exopod 1.15 times longer than basipodite, setose; endopod ( Fig. 5L View FIGURE 5 ) small, 0.4 of exopod length, 3.3 times longer than distal width, tapering proximally, distally rounded with 7 very short marginal setae distolaterally, medial margin with acute distal lobe, medially margin with about 12 slender simple marginal spinules proximally, Male second pleopod ( Fig. 5M View FIGURE 5 ) with basipodite more robust than first, similarly setose; exopod ( Fig. 5N View FIGURE 5 ) about 1.2 times basipodite length, setose; endopod about 0.95 of exopod length, 6.0 times longer than wide, with appendices ( Fig. 5O View FIGURE 5 ) at about 0.4 of medial margin length; appendix masculina with corpus subcylindrical, 5.0 times longer than width, with three slender terminal spines, about 0.8 of corpus length, four similar spines along distal dorsal margin; appendix interna slightly exceeding appendix masculina, with few cincinnuli.

Uropods ( Fig. 4K View FIGURE 4 ) with protopodite distolaterally rounded; exopod 3.4 times longer than broad, lateral margin straight, with dense row of submarginal plumose setae ventrally, with small acute distal tooth with much larger mobile spine medially, diaeresis ( Fig. 5P View FIGURE 5 ) well marked; endopod about 0.8 of exopod length, 4.0 times longer than wide.

Measurements (mms) Holotype female, postorbital carapace; 2.8; carapace and rostrum, 6.0; total body length (approx.), 17.4; major second pereiopod chela, 2.7; minor second pereiopod chela, 2.3.

Systematic position: Periclimenes sarkanae appears to be most closely related to members of the obscurus species group ( Bruce, 1987; in press). Of these, the resemblance is closest to P. obscurus Kemp, 1922 . Periclimenes sarkanae differs from P. obscurus in the following characters:

Etymology: From sarkany, a dragon (Hungarian), the maiden name of my wife Marguite, my helper for many years.

Habitat: Littoral, from sandmud flat, in pools, with seagrass, Zostera capricorni Aschers., 1876 .

Parasites: Two shrimps were parasitized by hemiarthrinid bopyrids.

Remarks: The figures of P. obscurus by Kemp (1922: 145, fig. 14) may be slightly erroneous. They show a feebly produced inferior orbital angle with a distinctly postmarginal antennal spine. The figure provided for P. indicus ( Kemp, 1922:144, fig. 13) shows a similar condition. Specimens of P. indicus from Chilka Lake have recently been examined and the antennal spine in these is fully marginal in its position. Specimens of P. obscurus , found in association with a sponge from 22.0m, Zanzibar Harbour, Unguja, Zanzibar, have also been examined. These confirm that the antennal spine is marginal and also that the fourth thoracic sternite is broad, with low medially blunt transverse ridges separated by a small median notch, the fifth sternite with similar ridges, more strongly developed than on fourth sternite and slightly more acute medially. It can also be confirmed that the ambulatory propodal spines are about 0.25 of the dactyl length. In the Zanzibar specimens the second pereiopods were markedly unequal in all specimens.