Diogenes acanthochela, Komai & Liang & Yang, 2012
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publication ID |
https://doi.org/ 10.1080/00222933.2011.654279 |
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DOI |
https://doi.org/10.5281/zenodo.10536800 |
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persistent identifier |
https://treatment.plazi.org/id/6414D960-FFBF-FF88-FED7-55BB470AFCB7 |
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treatment provided by |
Felipe |
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scientific name |
Diogenes acanthochela |
| status |
sp. nov. |
Diogenes acanthochela sp. nov. ( Figures 1–5 View Figure 1 View Figure 2 View Figure 3 View Figure 4 View Figure 5 )
Material examined
Holotype: Leizou Bay , Guandong Province, 20 ◦ 10.20 ′ N, 110 ◦ 56.40 ′ E, 10 m, 15 April to 15 May 2007, male (sl 5.3 mm; No. 6), IOCAS-MBM 119736 . GoogleMaps
Paratype: same data as holotype, one male (sl 7.1 mm; No. 7), CBM-ZC 10521 GoogleMaps .
Description
Shield ( Figure 1A View Figure 1 ) nearly subquadrate, almost as long as broad or slightly broader than long; anterior margin between rostrum and lateral projections slightly concave, with 3–6 tiny tubercles near each base of lateral projection; anterolateral margins sloping, with small spines at lateral angle; posterior margin truncate; dorsal surface with some transverse spinulose ridges laterally. Rostrum broadly rounded or terminally faintly bilobed; lateral projections each with small submarginal spine. Anterior part of branchiostegite with row of about 10 small spines on dorsal margin, no spine at anterior angle; lateral surface almost smooth, glabrous ( Figure 1B View Figure 1 ).
Ocular peduncles ( Figure 1A View Figure 1 ) about 0.6 times as long as shield, moderately stout; cornea slightly inflated, corneal width about 0.3 of length of ocular peduncle. Ocular acicles with straight inner margins, slightly convex anterolaterally, with 2 or 3 prominent spines and 7–9 spinules decreasing in size laterally, not extending to entire length of terminal margin. Intercalary rostriform process reaching nearly to distal end of ocular acicles, slightly broadened basally, tapering to slender acute tip.
Antennular peduncles ( Figure 1A View Figure 1 ) overreaching distal corneal margins by 0.8–0.9 length of ultimate segment and extending as far as antennal peduncles. Ultimate segment with some setae on dorsal surface and tufts of setae distally on both ultimate and penultimate segments; basal segment with row of minute spinules on distolateral margin.
Antennal peduncles ( Figure 1A, B View Figure 1 ) overreaching distal corneal margins by 0.8 length of fifth segment. Fifth segment with two rows of moderately long to long stiff setae ventrally; fourth and third segments unarmed; second segment with strong spine at dorsolateral distal angle and small but distinct spine at dorsomesial distal angle, ventrodistal margin with row of spinules; first segment with row of spinules on distal margin laterally. Antennal acicle falling short of distolateral margin of fourth segment, terminating in simple or bifid spine, bearing seven or eight strong accessory spines on mesial margin and occasionally with one spine on lateral margin, and with some tufts of short stiff setae on both lateral and mesial margins. Antennal flagellum ( Figure 1C View Figure 1 ) less than twice of shield length, articles with paired long, setulose setae ventrally and few additional short setae, forming cast net-like structure.
Third maxilliped ( Figure 1D View Figure 1 ) moderately slender. Carpus unarmed on dorsodistal margin. Ischium-basis fused segment with five strong, corneous-tipped spines (three on ischium and two on basis) on mesial surface ( Figure 1E View Figure 1 ). Exopod reaching distal margin of carpus.
Left cheliped ( Figure 2A–E View Figure 2 ) large but not particularly elongate in male; not particularly setose. Chela strongly compressed, about 1.5 times longer than wide. Dactylus distinctly longer than palm, somewhat curved; three rows of spines on upper margin, spines in middle row distinctly larger than those in lateral or mesial rows; outer surface with scattered spines or tubercles increasing in size proximally and ventrally, shallowly sulcate along midline; cutting edge with single row of blunt but distinct calcareous teeth; inner surface with longitudinal row of small spines accompanied by distinct groove along midline and one additional row of tubercles adjacent to cutting edge. Palm slightly shorter than carpus; upper surface with small spines arranged in three irregular longitudinal rows; outer surface generally convex, but shallowly depressed at base of fixed finger, having covering of small spines or spinules increasing in size dorsally, but without pronounced crest or longitudinal row(s) of spines; proximal margin distinctly delimited by row of small spines; lower margin faintly sinuous in outer view (including fixed finger), with double row of small spines extending to tip of fixed finger and continuous to proximal margin; inner surface with scattered, numerous tiny tubercles. Fixed finger very slightly deflexed, not curved outward; outer surface not particularly elevated along midline, with scattered small spines increasing in size toward cutting edge, but without distinct row of tubercles or ridge; inner surface with scattered small tubercles proximally; cutting edge with row of blunt but conspicuous calcareous teeth (middle tooth strongest), subterminal concavity receiving tip of dactylus. Carpus wider than long, with single row of moderately large spines with curved tips on upper margin; outer surface convex, with scattered numerous small spines or spine-like tubercles decreasing in size ventrally, dorsodistal margin finely spinulose; lower angle with prominent spine; mesial surface with scattered small spines or spinules and median row of small spines in proximal half; ventral surface with few tiny tubercles. Merus about as long as high; dorsal surface narrowing proximally and forming blunt crest in proximal half, bearing small spines over entire length; tufts of long stiff plumose setae present on dorsal surface; dorsodistal margin with row of sharp spines; lateral surface with scattered tiny tubercles, distolateral margin minutely spinulose, ventrolateral margin with row of small spines; mesial surface nearly smooth, ventromesial margin with row of small spines and one prominent spine at proximal angle; ventral surface with scattered minute tubercles and tufts of short setae. Ischium with two low protuberances on ventral surface and row of spinules on ventrolateral distal margin.
Right cheliped ( Figure 3A–D View Figure 3 ) moderately stout, setose; chela 1.8 times longer than wide, tips of fingers crossing. Dactylus only slightly curved, about 2.9 times longer than palm; dorsal surface with three irregular longitudinal rows of small spines and accompanying tufts of long stiff setae; mesial surface with median row of small spines extending beyond midlength and accompanying tufts setae and prominent groove inferior to midline in proximal half; ventral surface nearly smooth, with tufts of moderately long stiff setae laterally; cutting edge with row of small, acute, calcareous teeth over entire length. Palm about half length of carpus; dorsal surface with tufts of stiff setae and four irregular longitudinal rows of small spines, of them two rows extending onto fixed finger (spines strongest on fixed finger), lateral margin delimited by row of spinules extending onto fixed finger, dorsomesial face with numerous scattered spines; mesial surface with some small tubercles; ventral surface very slightly convex, with three rows of tiny tubercles laterally, extending onto fixed finger. Carpus with dorsolateral and dorsomesial rows of spines (spines of dorsomesial row stronger than those of dorsolateral row), dorsal surface with few spinules proximally; lateral surface with scattered tiny tubercles or spinules, distolateral margin with row of spinules; mesial surface with single row of spinules adjacent to dorsal margin and median row of tiny tubercles, distomesial margin with row of tiny tubercles extending ventrally. Merus with row of spines decreasing in size proximally and tufts of setae on dorsal margin, dorsodistal margin with six moderately small spines; lateral surface with scattered simple or bifid tiny tubercles and tufts of short setae, ventrolateral margin only delimited in distal part, with small spines or spinules; mesial surface nearly smooth, with tiny tubercles adjacent to ventromesial margin, ventromesial margin with row of spinules; ventral surface with scattered tiny tubercles and tufts of setae. Ischium unarmed on ventromesial margin; ventrolateral distal margin with row of tiny tubercles; some small protuberances present on ventral surface.
Ambulatory legs ( Figures 4A, B View Figure 4 , 5A–C View Figure 5 ) moderately long and stout; left third having stronger armature than other legs. Dactyli about 1.5–1.6 times as long as propodi and 8.5–9.0 times longer than wide; dorsal surfaces each with row of sparse short stiff setae and row of spinules laterally (in proximal 0.3–0.4 in second, proximal 0.2 in right third, proximal half in left third) and with row of dense stiff setae mesially; lateral surfaces each with shallow median sulcus running over entire length and median row of short sparse setae; mesial surfaces each with short median sulcus and median row of setae proximally, otherwise nearly flat, flanked by rows of moderately long stiff setae; ventral surfaces rounded, each with row of short stiff setae, unarmed (second and right third) or armed with some minute tubercles proximally (left third). Propodi slightly curved, distinctly longer than carpi; dorsal surfaces each with two rows of small spines and tufts of short stiff setae; lateral surfaces each with one row of small spines adjacent to dorsal margin (second and right third) or with two rows of minute spinules dorsally and one row of tiny tubercles ventrally in addition to dorsal row of small spines (left third); mesial surfaces each with two rows of small spinules (in third, ventral spinules reduced to minute tubercles); ventral margins smooth (right second and right third) or with row of small spines (left third) or spinules (left second). Carpi each with row of small spines increasing in size distally and tufts of setae on dorsal margin; lateral surfaces each with median row of minute tubercles accompanied by tufts of short setae and additional row of small tubercles (second) or small low protuberances ventral to median row (third), and vertical short row of spinules along distal margin; mesial surfaces each with median row of tufts of short setae. Meri with dorsal and ventral tufts of long setae; dorsal margins each with one or two rows of small spines or spinules, distalmost spine largest; lateral surfaces with spinules dorsally and ventrally, otherwise smooth; mesial surfaces each with row of long plumose setae adjacent to dorsal margin; ventral surfaces each with two rows of spinules (spinules on lateral row often reduced to tiny protuberances). Ischia each with one or few rounded protuberances on ventral surface.
Coxae of chelipeds and ambulatory legs with large blister-like protuberances.
Fourth pereopods chelate ( Figure 1F View Figure 1 ). Propodi each with small spine on dorsodistal margin; rasp consisting of more than 10 rows of corneous scales. Carpi each with small dorsodistal spine.
Anterior lobe of sixth thoracic sternite (of third pereopods) ( Figure 1G View Figure 1 ) distinctly bilobed, each lobule with 1 spinule or tiny tubercle anterolaterally.
Telson ( Figure 1H View Figure 1 ) with small median cleft, terminal margin slightly oblique on left, nearly transverse on right, both with small, unequal spines; lateral margin of left posterior lobe minutely denticulate, with some submarginal spines (posteriormost one or two spines prominent).
Coloration
Based on formalin preserved specimen: Shield generally light brown. Ocular peduncles and antennular peduncles pale brown; corneas black. Antenna with second segment and antennal acicle brown, fifth segment and flagellum white. Chelipeds and ambulatory legs generally light brick red.
Distribution
Known only from the type locality, Leizou Bay, Guandong Province; 10 m. Remarks
The present new species is referred to the Diogenes edwardsii (De Haan, 1849) species group by the intercalary rostriform process being marginally smooth and not reaching beyond the ocular acicles, the antennal peduncle distinctly overreaching the distal corneal margin, and the antennal flagellum having long paired setae on the distal margin of each article ventrally ( Asakura and Tachikawa 2010). Diogenes acanthochela sp. nov. is readily distinguished from other species in this group by a combination of the following characters: left chela with spinose upper margin and outer surface, but without distinct crest or row(s) of spines; merus of left cheliped with one prominent spine on ventromesial margin proximally; cutting edges of fingers of right chela armed each with row of small acute teeth over entire length; dorsal margin of dactylus of left third pereopod with row of spinules; propodi and carpi of ambulatory legs serrated with row(s) of spines, propodus of left third with additional rows of spinules on lateral surface. Diogenes spinulimanus Miers, 1880 may be similar to D. acanthochela sp. nov. in the armature of the left chela ( Miers 1880), but the former differs from the latter in the non-denticulate ocular acicles and the smooth dactyli of the ambulatory legs.
Etymology
The specific name is a combination of the Greek words “acanthus” (= spiny) and “chele” (= claw), in reference to the strongly spinose left chela of this new species.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.