Philocheras anthonyi, Taylor, 2010

Taylor, Joanne, 2010, The sand shrimp genus Philocheras (Caridea: Crangonidae) from the continental margin of Western Australia including the description of a new species and a key to Australian species *, Zootaxa 2372 (1), pp. 157-168 : 159-163

publication ID	https://doi.org/ 10.11646/zootaxa.2372.1.16
DOI	https://doi.org/10.5281/zenodo.5312796
persistent identifier	https://treatment.plazi.org/id/CD1387F0-B117-1E63-FF44-F436FAFA2FBA
treatment provided by	Felipe
scientific name	Philocheras anthonyi
status	sp. nov.

Treatment

Philocheras anthonyi View in CoL sp. nov.

( Figs. 1 View FIGURE 1 , 2 View FIGURE 2 )

Type material. Holotype. Australia, Western Australia, Imperieuse L 23 east transect, 17°35.98'S, 118°59.08'E to 17°38.56'S, 119°01.26'E), 222 m, 16.VI.2007 (stn SS05-2007 063), WAM C40390 (male, pocl 10.6 mm); paratypes: same locality, NMV J57302 View Materials (2 ov. females, pocl 9.2–9.7 mm). GoogleMaps

Etymology. Named for my husband, Anthony David Taylor.

Description. Based on holotype male. Body stout ( Fig. 1A View FIGURE 1 ). Rostrum ( Fig. 1B View FIGURE 1 ) with distal margin deeply excavate with lateral horns (bifid), 0.18 of carapace length, directed forward, reaching beyond anterior margin of cornea of eyes; dorsal surface ( Fig. 1B View FIGURE 1 ) deeply concave; lateral margins elevated, without setae, orbital margin without setae. Carapace slightly longer than broad; surface without setae or pubescence; without postorbital longitudinal suture; dorsal midline carinate with an indistinct discontinuous middorsal ridge extending from mid-dorsal spine to posterior margin; first tooth (epigastric tooth) arising 0.15 of carapace length; posterior to antennal tooth is a small tooth positioned in line with epigastric tooth followed by a discontinuous ridge, hepatic tooth arising anteriorly to level of epigastric tooth; branchial carina present; orbital margin concave, without cleft; antennal tooth broad, acute; branchiostegal tooth large, nearly reaching dorsodistal margin of antennal basicerite.

Abdomen ( Fig. 1A View FIGURE 1 ) widest at first somite, becoming narrow at fifth somite. First somite ( Fig. 1C View FIGURE 1 ) with distinct transverse carina along posterodorsal margin on tergum, without median carina; lateral longitudinal carina present but indistinct. Second somite ( Fig. 1C View FIGURE 1 ) with two faint transverse carinae on tergum; posterodorsal margin without median notch. Third somite ( Fig. 1C View FIGURE 1 ) with distinct median carina; tergum with four carinae, posterodorsal margin with median notch. Fourth somite ( Fig. 1D View FIGURE 1 ) with median carina, posterodorsal margin with shallow median notch, tergum and pleuron sculptured by transverse carinae. Fifth somite ( Fig. 1D View FIGURE 1 ) with median carina bifurcate posteriorly; tergum with transverse carina laterally. Sixth somite ( Fig. 1E View FIGURE 1 ) 1.4 times longer than fifth somite, with two submedian carinae; posterolateral process rounded; posterventral angle forming subacute tooth. Telson ( Fig. 1F View FIGURE 1 ) 1.8 times longer than sixth somite, tapering posteriorly and terminating in small triangular projection; dorsal surface with median sulcus, lacking dorsolateral spines; dorsolateral ridges distinct along entire length of telson.

First to fifth pleonal sternites each with blunt median tubercle.

Antennular peduncle ( Fig. 1B View FIGURE 1 ) just falling short of midlength of antennal scale. First segment longer than distal 2 segments combined, dorsal surface somewhat excavate to accommodate eye-stalk; distolateral angle produced, reaching anterior margin of first segment. Second segment about as long as wide, with slightly produced distolateral angle. Third segment narrower than second segment. Lateral flagellum overreaching distal margin of antennal scale by about one third, composed of approximately 35 articles (basal article occupying about 0.3 length). Antennal scale with distolateral tooth extending beyond rounded distal lamella.

Mouthparts not dissected.

First pereopod ( Fig. 2A, B View FIGURE 2 ) stout, overreaching distal margin of antennal scale by half length of palm; palm 3.0 times longer than wide; cutting edge oblique, with submarginal row of short setae dorsally and ventrally; pollex basally articulated, straight; dactylus curved; carpus short, with small ventrodistal tooth on lateral margin and cluster of grooming setae on mesial surface; merus large dorsodistal margin rounded, distolateral margin with 1 blunt tooth, ventral margin sparsely setose; exopod absent. Second pereopod ( Fig. 2C View FIGURE 2 ) reaching distal margin of carpus of anteriorly extended first pereiopod, chelate; dactylus 1.8 length of palm, without unguis; chela 0.78 length of carpus, with rows of long stiff setae on dorsal and ventral margins; pollex without unguis; carpus half length of merus, with long setae on each dorsal and ventral margins; merus and ischium with row of long setae on dorsal and ventral margins; ischium slightly shorter than merus. Third pereopod ( Fig. 2D View FIGURE 2 ) very slender, dactylus 0.38 length of propodus, terminating in acute tip; carpus elongate, 1.69 times longer than distal two segments combined; merus slightly longer than ischium. Fourth pereopod ( Fig. 2E View FIGURE 2 ) moderately stout; dactylus 0.72 length of propodus, slender, curved; ventral surface of dactylus smooth; propodus with stiff setae marginally; carpus 0.60 length of propodus; merus and ischium with long setae on dorsal and ventral surfaces, merus about 1.25 times longer than ischium and about 7.8 times longer than high. Fifth pereopod ( Fig. 2E View FIGURE 2 ) dactylus 0.72 length of propodus, slender, slightly curved; ventral surface of dactylus smooth; propodus with stiff few setae marginally; carpus 0.60 length of propodus; merus and ischium with sparse setae on dorsal and ventral surfaces, merus about twice length of ischium and about 9.4 times longer than high.

Pleopods with stout protopods. Endopod of first pleopod ( Fig. 2G View FIGURE 2 ) about 0.4 length of exopod, tapering distally; endopods of second ( Fig. 2H View FIGURE 2 ) and third pleopods ( Fig. 2I View FIGURE 2 ) 0.6-0.7 length of exopods, with appendix internae. Appendix masculina on second pleopod distinctly longer than appendix interna but not reaching tip of endopod, armed with several long setae on subtruncate distal margin.

Endopod of uropod ( Fig. 1F View FIGURE 1 ) moderately narrow, longer than exopod, overreaching tip of telson, tapering distally; exopod falling short of tip of telson, lateral margin nearly straight, terminating in small tooth.

Colour in life. First pereopod has distinctive red ‘spotty’ pigmentation on the dorsal surface and part of lateral and mesial surface of posterior end of propodus.

Distribution. Australia. Western Australia (17°35'59''S, 118°59'05''E to 17°38'34''S, 119°01'16''E), 222 m.

Remarks. This new species shares a bifid rostrum with P. angustirostris and P. incisus but is easily distinguished from them by the smooth lateral margin of the antennal scale which lacks a tooth or serration. It can also be distinguished by the presence of a middorsal carina on abdominal somites 3-6 and by the number and arrangement of dorsal spines on the carapace. The red pigmentation on the first pereopod of freshly collected material makes it quite distinctive from other Philocheras collected off Western Australia.