taxonID	type	description	language	source
03B087FADC1FFFCFC798FDAAFBA12E77.taxon	type_taxon	Type species. Pinnotheres palaensis Bürger, 1895, by subsequent designation (Manning 1993 b).	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1FFFCAC798FD1BFBC52ACA.taxon	description	(Figs. 1, 2)	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1FFFCAC798FD1BFBC52ACA.taxon	materials_examined	Type material. HOLOTYPE: ZRC 1965.11.24.49, male (cl 2.3 mm, cw 2.4 mm), Paye or Paway Island, Mergui Archipelago, Myanmar, 11 ° 25 ’ 00 ” N, 98 ° 31 ’ 00 ” E, coral reefs, shore collecting, from Malleus albus Lamarck, RIMSS Investigator, stn 593, 24 February – 3 March 1914. PARATYPE: ZRC 1965.11.24.50, 1 ovigerous female (cl 3.6 mm, cw 4.6 mm), collected together with holotype.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1FFFCAC798FD1BFBC52ACA.taxon	description	Description. MALE: Carapace irregularly subcircular. Front produced, anterior margin straight in dorsal view. Anterolateral margins poorly defined. Dorsum smooth, very few, minute, scattered setae; dorsal midline convex in profile. Epistome with narrow, triangular, interantennular septum; median buccal margin with acute median point. Antennular sinus smaller than orbit; antennules folded slightly obliquely. Antennal articles 1 and 2 fused to epistome. Eyes visible in dorsal view, filling orbit, cornea pigmented. Maxilliped 3 ischiomerus length about twice width; inner proximal margin convex; inner distal margin with blunt, obtuse angle; outer margin strongly convex. Carpus shorter than propodus. Propodus spatulate, gently tapering in distal half, apex rounded, dorsally and distal tally setose, length 4 × dactylus length. Dactylus digitiform, distally setose, inserted slightly distal to propodal midlength, apex not reaching end of propodus. Exopod inner margin straight, outer margin convex; flagellum with 2 articles, distally setose. Chelipeds stout, inflated, symmetrical from left to right, surfaces setose. Dactylus and pollex relatively straight, crossing distally, without gape. Dactylus occlusal margin with triangular tooth proximal to midlength, margin straight in distal half, minutely denticulate. Pollex occlusal margin with blunt triangular tooth proximal to midlength, straight in distal half, sparsely setose; with fringe of setae on inner ventral margin extending to proximal end of palm. Propodus palm dorsal margin 1.1 × height, as long as dactylus; ventral margin almost straight. Carpus unarmed. Pereopods 2 – 5 (walking legs 1 – 4) unarmed, symmetrical from left to right; covered in short, upright setae. Relative lengths in decreasing order: P 4> P 3> P 2> P 5. P 4 merus 0.5 × pcl. P 2 – 3 dactylus length subequal, 0.6 × propodus length, evenly arcuate, distally spiniform. P 4 dactylus 0.7 × propodus length, slightly curved, styliform. P 5 dactylus 1.1 × propodus length, styliform but thicker and straighter than P 4 dactylus; surfaces covered in upright setae, of similar length on flexor and extensor margins; flexor margin unarmed. Relative dactylus lengths: P 5> P 4> P 3 = P 2. Thoracic sternum anterior margin shallowly concave medially; sternites 1 – 3 indistinguishably fused; sternopleonal cavity reaching level of sternite ¾ suture. Pleon slender, margins evenly converging distally; comprising 6 free somites and telson, widest at somites 1 – 3; telson wider than long, apex rounded. Gonopod 1 elongate, slender, strongly arcuate, dorsoventrally compressed, about ¾ length of pleon, tapering to simple apex; margins setose, longest on outer margin. Gonopod 2 endopod simple, about ¼ length of gonopod 1; exopod short, slender, about ¼ length of endopod. Pleopods 3 – 5 absent. FEMALE: Carapace ovate, slightly wider than long. Front weakly produced, anterior margin broadly rounded in dorsal view. Anterolateral margins poorly defined. Dorsum smooth, very few, minute, scattered setae; dorsal midline convex in profile. Epistome with narrow triangular interantennular septum; median buccal margin with obtuse median point. Antennular sinus of similar size to orbit; antennules folded slightly obliquely. Antennal articles 1 and 2 fused to epistome. Eyes not visible in dorsal view, filling orbit, cornea pigmented. Maxilliped 3 ischiomerus length about twice width; inner proximal margin convex; inner distal margin with blunt, obtuse angle; outer margin strongly convex. Carpus shorter than propodus. Propodus spatulate, gently tapering in distal half, apex rounded, dorsally and distally setose, length 0.5 × dactylus length. Dactylus digitiform, distally setose, inserted slightly distal to propodal midlength, apex reaching end of propodus. Exopod inner margin straight, outer margin convex; flagellum with 2 articles, distally setose. Chelipeds symmetrical from left to right, surfaces setose. Dactylus and pollex relatively straight, crossing distally, without gape. Dactylus occlusal margin with blunt triangular tooth proximal to midlength, gently sinuous margin in distal half, sparsely setose. Pollex occlusal margin with blunt triangular tooth proximal to midlength, gently curved distal half, sparsely setose; with fringe of short setae on inner ventral margin. Propodus palm dorsal margin 1.3 × height, 0.9 × length of dactylus; ventral margin almost straight. Carpus unarmed. Pereopods 2 – 5 (walking legs 1 – 4) unarmed, covered in short, upright setae, most pronounced on flexor and extensor margins of merus, carpus, propodus, and dactylus. P 2, 3 and 5 similar, symmetrical from left to right; right P 4 length 1.2 × longer than left; relative lengths in decreasing order: P 4> P 5> P 3> P 2. Longer P 4 merus 0.5 × pcl. P 2 – 3 dactylus 0.5 × propodus length, evenly arcuate, distally spiniform, P 3 dactylus slightly longer that of P 2. P 4 dactylus styliform, unarmed, 0.9 × propodus length (right), 0.8 × propodus length (left). P 5 dactylus 1.1 × propodus length, styliform but thicker than P 4 dactylus; surfaces covered in upright setae, slightly longer on flexor margin; flexor margin unarmed; apex a short slender spine. Relative dactylus lengths: P 5> P 4> P 3> P 2. Thoracic sternum anterior margin shallowly concave medially; sternites 1 – 3 indistinguishably fused. Pleon of 6 free somites and telson, extending to buccal region, covering bases of walking legs.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1FFFCAC798FD1BFBC52ACA.taxon	biology_ecology	Host. Malleus albus Lamarck, 1819 (Malleidae).	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1FFFCAC798FD1BFBC52ACA.taxon	etymology	Etymology. Named pollus, small, alluding to the diminutive adult size of the species.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1FFFCAC798FD1BFBC52ACA.taxon	discussion	Remarks. Arcotheres pollus sp. nov. is readily separated from all known congeners by the finely setose carapace (glabrous in congeners), distinctly setose pereopods in females with setose cheliped (P 1) surfaces and setose flexor and extensor margins of the merus, carpus, propodus and dactylus of P 2 – 5. The cheliped setation in females of other species of Arcotheres is limited to the fringe on the lower margin of the palm, a small brush of setae sometimes on the inner margin of the carpus, and scattered setae on the occlusal margins and tips of the fingers (Campos 2001; Ahyong & Ng 2007 a; Ng 2018 b; Trivedi et al. 2018). On the walking legs of females of other species of Arcotheres, the P 5 dactylus is always setose, but P 2 – 5 are otherwise almost glabrous, at most with a few setae on the flexor margin of the dactylus and P 2 – 4, and sometimes with setae on the flexor margin of P 2 – 5 propodi. The male of A. pollus is setose as in the female, but too few males of other species of Arcotheres are known to permit a comprehensive comparison. As with the female, the carapace and cheliped setation will separate male A. pollus from known males of other species of Arcotheres, which lack dorsal carapace setae and or setae on the outer surface of the palm. As in other known males of Arcotheres, the G 2 exopod is present in A. pollus. Arcotheres pollus is morphologically nearest to those species in the genus with females having a transversely ovate carapace (Fig. 2 A) and long, slender, almost styliform dactyli of P 4 and 5 that are about twice the length of the P 2 and 3 dactyli (Fig. 2 H, L, M): A. boninensis (Stimpson, 1858), A. pernicola (Bürger, 1895) and A. purpureus (Alcock, 1900). Aside from the pereopodal setation, A. pollus is readily separated from each of the aforementioned species by the shape of the propodus of maxilliped 3, which is distally thicker and less tapering (Fig. 2 B versus Alcock & McArdle 1902: pl. 57 fig. 6 b; Bürger 1895: pl 10 fig. 16; Dai & Yang 1991: fig. 210.2), and the absence of one or more rows of denticles on the distoflexor margin of the dactylus of P 5 (Fig. 2 M). Arcotheres boninensis and A. pernicola have two short rows of distoflexor spines on the P 5 dactylus, and A. purpureus, one row (Trivedi et al. 2019). With males and females already mature by cl 2.3 mm and 3.6 mm, respectively, A. pollus is the smallest known species of the genus. The next smallest species of Arcotheres appears to be A. exiguus, being mature (at least in females) by cl 4.6 mm (cf. Ahyong & Ng 2007). The type material of A. pollus was taken from the hammer oyster (Malleus albus) during shore collecting on coral reef. Other invertebrates taken from the same station, include a sipunculan worm (Sipunculus robustus Keferstein, 1865; Prashad 1936), polychaete worms (Sabellaria spinulosa Leuckart, 1927, Branchiomma intermedium Beddard, 1887, Sabellastarte indica Savigny, 1822; Fauvel 1932), and a mud shrimp (Upogebia kempi Sankolli, 1972; Sankolli 1972).	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1FFFCAC798FD1BFBC52ACA.taxon	distribution	Distribution. Known only from the type locality, Paway Island, Myanmar.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1AFFCAC798F89EFC452BB8.taxon	type_taxon	Type species. Pinnotheres ortmanni Bürger, 1895, by original designation.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1BFFC9C798FF31FC902FC6.taxon	description	(Figs. 3, 4)	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1BFFC9C798FF31FC902FC6.taxon	materials_examined	Type material. HOLOTYPE: MNHN IU- 2013 - 1307, spent female (cl 3.6 mm, cw 4.0 mm), west of Tab Island, Papua New Guinea, 1 – 17 m, from Holothuria (Actinopyga) echinites, PAPUA NIUGINI PR 118, 28 November 2012.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1BFFC9C798FF31FC902FC6.taxon	description	Description. FEMALE: Carapace rounded-subquadrate, high, vaulted, slightly wider than long, widest near midlength. Front weakly produced, anterior margin weakly concave in dorsal view. Anterolateral margins poorly defined. Dorsum smooth, glabrous, outline of cardiac region weakly indicated by faint, shallow groove; anterior median groove absent; dorsal midline convex in profile. Epistome with narrow triangular interantennular septum; median buccal margin with acute, triangular median point. Antennular sinus of slightly larger than orbit; antennules folded slightly obliquely. Antennal articles 1 and 2 fused to epistome. Eyes partially visible in dorsal view, filling orbit, cornea pigmented. Maxilliped 3 ischiomerus length 1.7 × width; inner proximal margin convex; inner margin with blunt, obtuse angle slightly distal to midlength, margin on either side weakly concave; outer margin strongly convex. Carpus half propodus length. Propodus spatulate, gently tapering in distal half, apex rounded, dorsally and distally setose, length less than twice dactylus length. Dactylus sub-clavate, widest distal to midlength, apex rounded, distally setose, inserted slightly proximal to propodal midlength, apex almost reaching end of propodus. Exopod inner margin straight, outer margin convex; flagellum with 2 articles, distally setose. Chelipeds symmetrical from left to right. Dactylus and pollex relatively straight, crossing distally, without gape. Dactylus dorsal margin convex, smooth, proximally setose; occlusal margin with blunt triangular tooth proximal to midlength, gently sinuous margin in distal half, sparsely setose, minutely denticulate. Pollex occlusal margin with blunt triangular tooth and 2 rounded lobes proximally, remaining margin crenulate, gently curved, sparsely setose, minutely denticulate along distal half; with fringe of setae on inner ventral margin extending onto inner palm surface. Propodus palm outer surface smooth, glabrous; dorsomesial surface with scattered setae proximally; dorsal margin 1.4 × height, 1.1 × length of dactylus; ventral margin sinuous. Carpus unarmed, inner margin setose. Pereopods 2 – 5 (walking legs 1 – 4) symmetrical from left to right, unarmed; relative lengths in decreasing order: P 2 = P 3> P 4> P 5. P 3 merus length 0.4 × pcl. P 2 – 4 similar; merus extensor margin broadly convex, extensor and flexor margins setose proximally; carpus glabrous; dactylus and propodus flexor margins setose; dactyli subequal, stout, falcate, evenly arcuate, distally spiniform, length 0.4 × propodus length; basis anterior surface smooth, not granulate. P 5 merus tapering distally, distinctly shorter than P 2 – 4 merus, extensor and flexor margins margins straight, setose; propodus margins parallel, flexor margin setose; dactylus slender, weakly curved, almost straight, flexor margin setose but unarmed, 0.8 × propodus, twice length of P 2 – 4 dactyli. Thoracic sternum anterior margin shallowly biconcave medially; sternites 1 – 3 indistinguishably fused. Pleon of 6 free somites and telson, extending to buccal region, covering bases of walking legs.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1BFFC9C798FF31FC902FC6.taxon	biology_ecology	Host. Holothuria (Actinopyga) echinites (Jaeger, 1833) (Holothuriidae).	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1BFFC9C798FF31FC902FC6.taxon	etymology	Etymology. Name for B. Chopra, who discovered the B. deccanensis and for his major contributions to Indian Ocean carcinology.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1BFFC9C798FF31FC902FC6.taxon	discussion	Remarks. Buergeres choprai sp. nov. is the fourth recognised species of the genus, alongside B. ortmanni (Bürger, 1895) (type species) (Singapore and the Philippines), B. deccanensis (Chopra, 1931) (eastern India) and B. holothuriae (Semper, 1880) (Philippines). The new species is readily separated from B. holothuriae by the glabrous rather than tomentose outer surface of the cheliped palm of B. holothuriae and more subquadrate versus subcircular carapace outline. Buergeres choprai can be separated from P. ortmanni by the proportionally shorter P 5 dactylus (about twice versus triple length of the P 2 dactylus) and the setation of the P 2 – 4 meral extensor margins (sparely setose on the proximal half versus densely setose for at least three-fourths of the length in P. ortmanni) (cf. Ng & Manning 2003). In carapace shape and pereopodal features, Buergeres choprai most closely resembles B. deccanensis. Comparison with Chopra’s (1931) excellent figures and account shows that B. choprai differs from B. deccanensis in having proportionally shorter P 5 dactyli (distinctly shorter than the propodus extensor margin in B. choprai versus as long as extensor margin in B. deccanensis), the setose rather than glabrous dorsal proximal margin of the cheliped dactylus, and P 2 – 5 meral setation (extensor margin setose in B. choprai, glabrous in B. deccanensis; Chopra 1931: pl. 7 fig 4). Chopra (1931) also emphasised the presence of distinct grooves around the cardiac region and along the anterior midline as characteristic of B. deccanensis; in B. choprai the cardiac region is at most weakly demarcated and no median groove is evident. Well-marked carapace regions are uncommon in Pinnotheridae and Buergeres, and apparently unique to B. deccanensis. Males of B. choprai are currently not known.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC1BFFC9C798FF31FC902FC6.taxon	distribution	Distribution. Presently known only from the type locality.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC19FFC6C798FB9FFBDD2D36.taxon	materials_examined	Type material. NEOTYPE: ZRC 2003.59, female (cl 9.5 mm, cw 11.4 mm), Pulau Salu, northeastern Singapore, coral reef, exposed at edge of reef, in holothurian, coll. R. U. Gooding, 28 April 1967 (neotype of Pinnotheres ortmanni Bürger, 1895). Other material examined. ZRC 1965.11.24.14 – 15, 2 females (both with cl 11.8 mm, cw 12.5 mm), Singapore, no other data; ZRC 2018.0760, 2 females (cl 11.7 mm, cw 12.3 mm; cl 9.0 mm, cw 10.3 mm), Ambon, Moluccas, Indonesia, inside sea cucumbers, probably Holothuria scabra Jaeger, 1833 (Holothuriidae), Ambon Marine Laboratory, coll. S. Dwiono, November 1996.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC19FFC6C798FB9FFBDD2D36.taxon	discussion	Remarks. Of the four species originally placed in Buergeres by Ng & Manning (2003), three were described from the Philippines (Pinnotheres holothuriae Semper, 1880, P. ortmanni Bürger, 1895 (type species) and P. tenuipes Bürger, 1895) and one from eastern India (P. deccanensis Chopra, 1931). Most species of Buergeres have been well characterised: Chopra (1931) provided a good description and figures of B. deccanensis and Ng & Manning (2003) redescribed B. holothuriae based on type material. The original type specimens of two Philippine species, B. ortmanni and B. tenuipes are lost. As such, Ng & Manning (2003) redescribed B. ortmanni based on a neotype and other material from Singapore. Buergeres tenuipes, however, has not been reported since it was first described, but the present reconsideration of the elementary original description and figures shows that it cannot be distinguished from B. ortmanni. Although the original holotype of B. tenuipes was about half the size of B. ortmanni, the two species share the same diagnostic features and are herein synonymized. Unfortunately, no Philippine material clearly identifiable with B. ortmanni or B. tenuipes is presently available (but see Remarks for Burgeres sp.). Therefore, to stabilize the taxonomy of B. tenuipes as a junior synonym of B. ortmanni, we herein designate the neotype of the latter (female, ZRC 2003.59) as the simultaneous neotype of B. tenuipes, rendering the two species objective synonyms of each other. As both species were described in the same paper (Bürger 1895), we here also select B. ortmanni to have priority over B. tenuipes.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC19FFC6C798FB9FFBDD2D36.taxon	distribution	Distribution. The Philippines, Singapore and now from Ambon, Indonesia.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC16FFC7C798FECFFB122D86.taxon	description	(Fig. 5)	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC16FFC7C798FECFFB122D86.taxon	materials_examined	Material examined. ZRC 2018.0784, 1 male (cl 5.3 mm, cw 5.6 mm), Manga Point, Bohol, Visayas, Philippines, 09 ° 42.1 ’ N, 123 ° 51.3 ’ E, 0 – 1 m, mangrove and mixed intertidal habitat, from Holothuria impatiens, PANGLAO 2004 stn M 24, 17 June 2004.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC16FFC7C798FECFFB122D86.taxon	description	Description. MALE: Carapace rounded, high, vaulted, slightly wider than long, widest near midlength. Front produced, anterior margin concave in dorsal view. Anterolateral margins poorly defined. Dorsum smooth, glabrous, regions scarcely indicated centrally; dorsal midline convex in profile. Epistome with narrow triangular interantennular septum; median buccal margin with obtuse, triangular median point. Antennular sinus of slightly larger than orbit; antennules folded slightly obliquely. Antennal articles 1 and 2 fused to epistome. Eyes visible in dorsal view, filling orbit, cornea pigmented. Maxilliped 3 ischiomerus length twice width; inner proximal margin convex; inner margin with blunt, obtuse angle slightly distal to midlength, margin on either side weakly concave; outer margin strongly convex. Carpus half propodus length. Propodus spatulate, gently tapering in distal half, apex rounded, dorsally and distally setose, length exceeding twice dactylus length. Dactylus sub-clavate, widest distal to midlength, apex rounded, distally setose, inserted at propodal midlength, apex not reaching end of propodus. Exopod inner margin straight, outer margin convex; flagellum with 2 articles, distally setose. Chelipeds symmetrical from left to right. Dactylus and pollex relatively straight, crossing distally, without gape. Dactylus dorsal margin convex, smooth, glabrous; occlusal margin with blunt triangular tooth proximal to midlength, otherwise straight, sparsely setose. Pollex occlusal margin with 2 blunt triangular teeth proximally, remaining margin weakly crenulate, straight, sparsely setose, minutely denticulate; with fringe of setae on inner ventral margin extending onto lower inner palm surface. Propodus palm outer surface smooth, glabrous; dorsal margin 1.3 × height, 1.1 × length of dactylus; ventral margin sinuous. Carpus unarmed, inner margin setose. Pereopods 2 – 5 (walking legs 1 – 4) symmetrical from left to right, unarmed; relative lengths in decreasing order: P 3 = P 4> P 2> P 5. P 3 merus length 0.5 × pcl. P 2 – 4 similar; merus extensor margin broadly convex, extensor and flexor margins sparsely setose; carpus glabrous; dactylus and propodus flexor margins setose; dactyli subequal, stout, falcate, evenly arcuate, distally spiniform, length 0.4 × propodus length; basis anterior surface smooth, not granulate. P 5 merus tapering distally, distinctly shorter than P 2 – 4 merus, extensor and flexor margins margins straight; propodus margins parallel, flexor margin setose; dactylus slender, weakly curved, almost straight, flexor margin setose but unarmed, 0.8 × propodus length, 1.3 × P 2 – 4 dactylus length. Thoracic sternum anterior margin concave medially; sternites 1 – 3 indistinguishably fused; sterno-pleonal cavity reaching level of sternite 3 / 4 suture. Pleon slender, margins evenly converging distally; comprising 6 free somites and telson, widest at somites 1 – 3; telson as wide as long, apex rounded. Gonopod 1 elongate, slender, gently arcuate, dorsoventrally compressed, about ¾ length of pleon, tapering to convex apex with short, obliquely directed spiniform tip; margins strongly setose. Gonopod 2 endopod simple, about ¼ length of gonopod 1; exopod short, slender, about half length of endopod. Pleopods 3 – 5 absent.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC16FFC7C798FECFFB122D86.taxon	biology_ecology	Host. Holothuria impatiens (Forskål, 1775) (Holothuriidae).	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC16FFC7C798FECFFB122D86.taxon	discussion	Remarks. Prior to the present study, knowledge of male Buergeres has been derived from a single specimen of B. deccanensis reported by Chopra (1931) (although without figures or description of the gonopods). We report here a male of an unidentified species of Buergeres from the Philippines (Fig. 5). It corresponds well to Buergeres in maxilliped 3 morphology and in the subequal P 2 – 4 dactyli that are all shorter and more strongly curved than the straight, elongate P 5 dactylus. Based on what is known of B. deccanensis, the P 5 dactylus is essentially straight in both sexes, but proportionally shorter in males; the present male reflects such a condition. The Philippine male differs from male B. deccanensis in carapace shape (rounded versus subquadrate), and given the locality, might be referable to either B. holothuriae or B. ortmanni, both of which occur in the Philippines (Bürger 1895; Ng & Man- ning 2003). The specific identity of the male cannot be confirmed at present because it was not associated with a known female, but we believe that it is probably B. ortmanni: the outer surface of the cheliped palm is glabrous as in female B. ortmanni (Fig. 5 D; Ng & Manning 2003: fig. 4 C), rather than tomentose as in female B. holothuriae (Ng & Manning 2003: fig. 5 D). Despite the unconfirmed identification, the present male is figured here to document its morphology, especially that of the gonopods. As in known males of Holotheres (see Ng & Manning 2003: fig. 1 I, 2 H), the G 1 of the present male is broadly curved, with a short, slender, obliquely directed apex (albeit proportionally shorter than in Holotheres) (Fig. 5 L). As in many other pinnotherids, the G 2 of the male Buergeres has a short but distinct exopod (Fig. 5 M, N; Ahyong et al. 2012; Ng & Ho 2016 a; Ng 2018 b; Ahyong 2019).	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC14FFC4C798FDBFFC582E58.taxon	type_taxon	Type species. Cancer pinnotheres Linnaeus, 1758, by original designation.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC14FFC3C798FD69FB8E2BB6.taxon	description	(Figs. 6, 7)	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC14FFC3C798FD69FB8E2BB6.taxon	materials_examined	Type material. HOLOTYPE: ZRC 2018.1391, male (cl 2.8 mm, cw 2.9 mm), west of Tabad Island, Papua New Guinea, 5 ° 08.26002 ’ S, 145 ° 48.71976 ’ E, 10 m, from Fulvia australis (G. B. Sowerby II, 1834) (Cardiidae), PAPUA NIUGINI stn PR 198, coll. A. Anker, 7 Dec 2012. PARATYPE: ZRC 2018.1392, female (cl 3.0 mm, cw 3.1 mm), collected together with holotype.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC14FFC3C798FD69FB8E2BB6.taxon	description	Description. MALE: Carapace subcircular. Front slightly produced, anterior margin weakly concave in dorsal view. Dorsum smooth, glabrous. Epistome with broad, triangular interantennular septum; median buccal margin with narrow, acute, median point. Antennular sinus of similar size to orbit; antennules folded obliquely. Antennal articles 1 and 2 fused to epistome. Eyes visible in dorsal view, filling orbit, cornea pigmented. Maxilliped 3 ischiomerus length about twice width; inner distal margin with prominent, obtuse angle, margin distal and proximal to angle straight; outer margin strongly convex. Carpus shorter than propodus. Propodus spatulate, tapering in distal half, apex rounded, dorsally and distally setose, length 2.8 × dactylus length. Dactylus digitiform, distally setose, inserted at propodal midlength, apex reaching to midway between insertion and end of propodus. Exopod inner margin straight, outer margin broadly convex; flagellum with 2 articles, distally setose. Chelipeds stout, inflated, symmetrical from left to right. Dactylus and pollex crossing distally, with distinct gape. Dactylus arcuate, dorsal margin arcuate, sparsely setose; occlusal margin setose, with blunt triangular tooth proximal to midlength, concave in distal half, with rounded dentate subdistal lobe near base of simple, falcate dactylar apex. Pollex relatively straight, apex simple, with fringe of short setae on inner ventral margin extending onto proximal half of palm; occlusal margin setose, irregularly and minutely dentate, with short spinules on distal half, with low subdistal lobe occluding with corresponding dactylar lobe when fingers closed. Propodus palm dorsal margin 1.3 × height, 1.2 × length of dactylus; scattered dorsal setae; ventral margin weakly concave. Carpus unarmed, inner margin setose. Pereopods 2 – 5 (walking legs 1 – 4) symmetrical from left to right, unarmed; extensor and flexor margins setose, P 3 and 4 also with natatory setae; relative lengths in decreasing order: P 3> P 4> P 2> P 5. P 2 basis anterior surface granulate. P 3 merus 0.6 × pcl. P 2 – 5 dactyli similar, evenly arcuate, distally spiniform, P 2 – 4 dactylus 0.6 × propodus length, P 5 dactylus 0.7 × propodus length. Relative dactylus lengths: P 2 = P 3 = P 4> P 5. Thoracic sternum anterior margin distinctly concave medially; sternites 1 – 3 fused; demarcation between sternites 2 and 3 partially indicated by transverse median groove; sterno-pleonal cavity reaching sternite ¾ suture. Pleon slender, margins evenly converging distally; comprising 6 free somites and telson, widest at somites 2 and 3; telson wider than long, apex rounded. Gonopod 1 elongate, slender, arcuate, dorsoventrally compressed, about 2 / 3 length of pleon, tapering to simple apex; margins setose, longest on outer margin. Gonopod 2 endopod simple, about ¼ length of gonopod 1; exopod short, slender, about as long as endopod. Pleopods 3 – 5 absent. FEMALE: Carapace subcircular. Front not produced, anterior margin weakly concave in dorsal view. Dorsum smooth, very few, minute, scattered setae. Epistome with broad, triangular interantennular septum; median buccal margin with narrow, acute, median point. Antennular sinus of similar size to orbit; antennules folded obliquely. Antennal articles 1 and 2 fused to epistome. Eyes not visible in dorsal view, filling orbit, cornea pigmented. Maxilliped 3 ischiomerus length about twice width; inner distal margin with prominent, obtuse angle, margin distal and proximal to angle straight; outer margin strongly convex. Carpus shorter than propodus. Propodus spatulate, tapering in distal half, apex rounded, dorsally and distally setose, length 3.2 × dactylus length. Dactylus digitiform, distally setose, inserted at propodal midlength, apex reaching to midway between insertion and end of propodus. Exopod inner margin straight, outer margin sinuous; flagellum with 2 articles, distally setose. Chelipeds symmetrical from left to right, surfaces sparsely setose. Dactylus and pollex relatively straight, crossing distally, without gape. Dactylus occlusal margin with blunt triangular tooth proximal to midlength, straight in distal half, sparsely setose, minutely denticulate. Pollex occlusal margin irregular, sparsely setose, minutely denticulate; with fringe of short setae on inner ventral margin. Propodus palm dorsal margin 1.5 × height, 1.2 × length of dactylus; ventral margin weakly concave. Carpus unarmed, inner margin setose. Pereopods 2 – 5 (walking legs 1 – 4) symmetrical from left to right, unarmed, setose on flexor and extensor margins of merus, carpus, propodus, and dactylus, P 3 – 4 also with natatory setae; relative lengths in decreasing order: P 3> P 4> P 2> P 5. P 3 merus 0.5 × pcl. P 2 basis anterior surface granulate. Dactyli similar, evenly arcuate, distally spiniform; P 2 – 4 dactyli 0.5 × propodus length, of P 5, 0.6 × propodus length. Relative dactylus lengths: P 3> P 2 = P 4> P 5. Thoracic sternum anterior margin shallowly concave medially; sternites 1 – 3 indistinguishably fused. Pleon of paratype yet to reach full size, reaching to, or almost to, but not covering coxa of walking legs; of 6 free somites and telson.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC14FFC3C798FD69FB8E2BB6.taxon	biology_ecology	Host. Fulvia australis (G. B. Sowerby II, 1834) (Cardiidae).	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC14FFC3C798FD69FB8E2BB6.taxon	etymology	Etymology. Named fulvia, after the genus name of the host; used as a noun in apposition.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC14FFC3C798FD69FB8E2BB6.taxon	discussion	Remarks. Nepinnotheres fulvia sp. nov. is readily distinguished from the majority of its congeners in having the maxilliped 3 dactylus distinctly under-reaching (Fig. 6 B, 7 B) rather than reaching to, or over-reaching, the apex of the propodus. Six species, however, also have a maxilliped 3 dactylus that distinctly under-reaches the propodus: N. cardii (Bürger, 1895) (type locality: Philippines), N. villosulus (Guérin, 1832) (type locality: Timor, Indonesia), N. glaberrimus (Bürger, 1895) (type locality: Philippines), N. rathbunae (Schmitt, McCain & Davidson, 1973) (type locality: Palau), N. rouxi (H. Milne Edwards, 1853) (type locality: Indian Ocean), and N. sanguinolariae (Pillai, 1951) (type locality: India). Female N. fulvia can be distinguished from N. cardii by the absence of the proximal occlusal tooth on the cheliped pollex (Fig. 7 E) (present in N. cardii; Ahyong & Ng 2007 a: fig. 22 B; Ng et al. 2019: fig. 1, 2 D), and strongly setose walking legs (Fig. 7 A, E – H) (glabrous in P. cardii except for flexor margins of propodi and dactyli; Ahyong & Ng 2007 a: fig. 22 A; Ng et al. 2019: fig. 1). Male N. fulvia can be separated from male N. cardii by the more slender maxilliped 3 propodus (length 3 × height versus 2 × height in N. cardii; Fig. 6 B, Ahyong & Ng 2007 a: fig. 22 F) and absence of a prominent rounded tooth on the distal one-third of the cheliped pollex occlusal margin (Fig. 6 E) (present in N. cardii; Ahyong & Ng 2007 a: fig. 22 E). Female N. fulvia can be readily separated from female N. villosulus (males presently unknown) by lacking the short tomentum that densely covers the entire external surface of the cephalothorax and pereopods, and from both sexes of N. sanguinolariae by the subcircular versus transversely ovate carapace. Nepinnotheres glaberrimus, known with certainty only from the male lectotype, differs from male N. fulvia by the position of the maxilliped 3 dactylus articulation (proximal to the midlength versus at the midlength in N. fulvia) and the presence of two prominent proximal teeth on the occlusal margin of the cheliped pollex (absent in N. fulvia). Nepinnotheres rouxi is known only from the type description, but, based on the maxilliped 3 of the holotype figured by H. Milne Edwards (1853: pl. 11 fig. 7), differs from N. fulvia by the comparatively narrow ischiomerus (length about 2.5 × width) with a broadly rounded, weakly produced inner distal angle of the ischiomerus (versus length about twice width with distinctly angular inner distal margin in the new species). Nepinnotheres rathbunae differs from N. fulvia in a similar way to N. rouxi. Another unusual feature of both sexes of N. fulvia is the presence of a granular anterior surface of the P 2 coxa (Figs. 6 J, 7 J) (although more prominent in the male than female); this feature has not been previously reported in pinnotherids, although it may have been overlooked. The male cheliped in N. fulvia sp. nov. is conspicuous among congeners for the large gape between the fingers and the presence of a denticulate subdistal lobe on the outer occlusal surface dactylus that occludes with a low swelling on the corresponding surface of the pollex, ‘ interlocking’ with the curved apices of the fingers. Of known males of Nepinnotheres, such an arrangement is otherwise known only in N. cardii (Bürger, 1895) (type locality: Philippines), N. bidentatus (Sakai, 1939) (type locality: Wakayama, Japan) and N. taichungae (Sakai, 2000) (type locality: Kaomei, Taiwan). The male of N. fulvia is mature, indicated by the strongly inflated cheliped and well developed gonopods (Fig. 6 A, E, L, M). As in N. affinis (Bürger, 1895) from the Philippines, the G 2 exopod in N. fulvia is of similar length to the endopod (Fig. 6 M; Ahyong et al. 2012: fig. 4 B, C). The female paratype of N. fulvia is apparently a late subadult, with the pleon broad but yet to reach full size to cover the coxa of the walking legs (Fig. 7 K). Although a late subadult, diagnostic features are already well developed by this stage in other species of Nepinnotheres, notably in the proportions of the maxilliped 3 articles and pereopodal setation, so we have little hesitation in recognising the novelty of N. fulvia.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
03B087FADC14FFC3C798FD69FB8E2BB6.taxon	distribution	Distribution. Presently known only from off Tabad Island, Papua New Guinea.	en	Ahyong, Shane T., Ng, Peter K. L. (2020): New species of pinnotherid crabs from Southeast Asia and Papua New Guinea (Crustacea: Decapoda: Brachyura). Zootaxa 4816 (3): 333-349, DOI: 10.11646/zootaxa.4816.3.4
