identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
03A73E01FFEFFFD4C8E1FA96FBE2F969.text	03A73E01FFEFFFD4C8E1FA96FBE2F969.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Pleonexes spencebatei Thacker & Myers & Trivedi 2026	<div><p>Pleonexes spencebatei sp. nov.</p><p>(Figs. 1–4)</p><p>Type material. Holotype: male, 8.0 mm (LFSC.ZRC-297), <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=69.07861&amp;materialsCitation.latitude=22.47889" title="Search Plazi for locations around (long 69.07861/lat 22.47889)">Okha</a> (22°28'44"N 69°04'43"E), Gujarat State, India, 12 January 2024, coll. D.R. Thacker . Paratypes: 8 males, 5.0–8.0 mm (LFSC.ZRC-298), same data as holotype .</p><p>Etymology. The new species is named in honour of late Charles Spence Bate, who established the genus Pleonexes . Charles Spence Bate is also known for his valuable contribution to the taxonomy of amphipods.</p><p>Description. Based on holotype, male, 8.0 mm.</p><p>Head. Head nearly as long as deep; ocular lobes prominent, inferior antennal sinus shallower than the superior one. Eyes medium-sized. Antenna 1 peduncular article 1 1.2× as long as article 2; article 2 3.5× as long as article 3; accessory flagellum absent. Antenna 2 peduncular article 3 subequal to article 4; article 5 0.2× as long as article 4; flagellum with 10 to 11 articles; peduncle 3.1× as long as flagellum (here measurement for the peduncle was taken from articles 2 to 5, as article 1 was damaged during dissection). Labrum (= upper lip) distally setose. Mandible molar well-developed, incisor 6 and 5 dentate in right and left mandibles, respectively; lacinia mobilis 5 and 6 dentate in right and left mandibles, respectively; accessory setal row with 4 setae in both right and left mandibles; palp 3 articulate, article 2 subequal to article 3. Labium (= lower lip) outer plate notched, inner lobes shorter than outer lobe. Maxilla 1 inner plate distal margin with 1 apical simple seta in both left and right; outer plate with 9 or 10 multi-cuspidate setae (left and right, respectively); palp 2 articulate, distal article with 8 setae apically and 5 on upper margin of both right and left. Maxilla 2 inner plate with apical simple setae and marginal plumose setae; outer plate with few apical setae, marginal setae very small and thin. Maxilliped inner plate with apical and marginal plumose setae; outer plate 12 large to small sized robust setae and 6 apical simple setae; palp 4 articulate, article 4 with a long dactylus.</p><p>Pereon. Gnathopod 1 coxa produced anteriorly; basis 2.1× as long as broad, anterior and posterior margin each with a pair of long setae; a large anterodistal lobe with 4 medium sized setae; posterodistal corner with a small seta; merus posterior margin with sparse setae; carpus anterior margin 0.6× as long as propodus, posterior margin moderately setose, anterodistal corner with 1 seta; propodus length: width 3.0:1.2, and 1.1× as long as basis, anterior margin with only 1 or 2 setae, posterior margin moderately setose, palm sigmoidal shaped with a large spine and several setae; dactylus as long as palm, inner margin crenated.</p><p>Gnathopod 2 coxa as long as broad; basis 2.0× as long as broad, anterior margin bare, posterior margin with a pair of setae, a large anterodistal lobe with 7 medium sized setae; merus posterodistal corner with a tuft of setae; carpus anterior margin 0.5× as long as propodus, anterodistal corner with a pair of setae, posterodistal corner with a tuft of setae; propodus length: width 3.0:1.4, 1.6× as long as basis, anterior margin with several small setae, anterodistal corner densely setose, posterior margin moderately setose and produced into a thumb-like process, anterodistal corner, palm acute, with a narrow V shaped cleft; dactylus as long as palm, inner margin crenated.</p><p>Pereopod 3 coxa 1.4× as long as broad; basis expanded, anterodistal corner with a pair of setae, posterior margin with 1 seta, posterodistal corner with 1 seta; merus 1.6× as long as broad; carpus 0.7× as long as merus; propodus subequal to merus; anterior margin with a tuft of setae, anterodistal corner with a tuft of setae, posterior margin sparsely setose, posterodistal corner with a tuft of setae; dactylus 0.6× as long as propodus.</p><p>Pereopod 4 coxa 1.5× as long as broad; basis slightly expanded, anterodistal corner with one seta, posterior margin sparsely setose; merus 1.9× as long as broad; carpus 0.6× as long as merus; propodus 0.9× as long as merus, anterior margin with few setae, anterodistal corner with a tuft of setae, posterior margin sparsely setose, posterodistal corner with a tuft of setae; dactylus 0.6× as long as propodus.</p><p>Pereopod 5 coxa 1.2× as long as broad; basis expanded, anterior margin with 2 setae, anterodistal corner with a pair of setae, posterodistal corner with 1 seta; merus 1.6× as long as broad; carpus 1.2× as long as merus; propodus 1.7× as long as merus, posterior margin with two distal robust setae.</p><p>Pereopod 6 basis expanded, anterior margin with 2 small setae, posterodistal corner with 2 setae; merus 0.7× as long as basis; carpus 0.8× as long as merus; propodus 1.1× as long as merus; dactylus 0.4× as long as propodus.</p><p>Pereopod 7 basis expanded, anterior margin bare; posterodistal corner with 1 seta; merus 0.7× as long as basis; carpus 0.9× as long as merus; propodus anterior margin with few simple setae and 4 distal robust setae, posterior margin and posterodistal corner each with a tuft of setae.</p><p>Pleon. Epimera 1–3 anteroventral corner rounded, ventral margin bare. Uropod 1 peduncle with a small rounded distoventral spur and row of setae on outer margin, peduncle 1.2× as long as inner ramus; inner ramus 1.1× as long as outer ramus; outer ramus with 8 marginal robust setae and 3 apical robust setae; inner ramus 7 marginal robust setae and 2 apical robust setae. Uropod 2 peduncle subequal to outer ramus; inner ramus 1.1× as long as outer ramus; outer ramus with 6 marginal robust setae and 3 apical robust setae; inner ramus with 8 marginal robust setae and 3 apical robust setae. Uropod 3 peduncle 1.5× as long as broad, with 5 distal robust setae, outer ramus with a pair of hooks like robust setae, inner ramus with 3 robust setae. Telson triangular, distal margin truncate, with 2 long apical setae and 2 marginal setae on each side.</p><p>Remarks</p><p>Pleonexes spencebatei sp. nov. can be readily placed within the group of congeners defined by the presence of a male gnathopod 2 propodus posterodistal margin produced into a thumb-like process. This group would include P. divisura (Shoemaker, 1933), P. kava (Myers, 1985), P. parakava (Peart, 2007), and P. nargessi Momtazi &amp; Maghsoudlou, 2020 . Based on the morphological differences given below, P. spencebatei sp. nov. is reliably differentiated from its close congeners.</p><p>Pleonexes spencebatei sp. nov. can be differentiated from P. divisura by the following characteristics: sigmoidal-shaped male gnathopod 1 palm (vs. evenly convex in P. divisura); gnathopod 2 propodus length 2.4× longer than broad (vs. propodus only 1.6× longer than broad in P. divisura); pereopod 5 and pereopod 7 propodus distal part expanded and with 2 and 4 robust setae respectively (vs. pereopod 5 to pereopod 7 propodus distal part expanded and with 4 robust setae each in P. divisura); telson apically truncated (vs. rounded in P. divisura).</p><p>Pleonexes spencebatei sp. nov. can be differentiated from P. kava by the following characteristics: mandible palp article 2 subequal to article 3 (vs. palp article 2 1.5× longer than article 3 in P. kava); sigmoidal-shaped male gnathopod 1 palm (vs. evenly convex in P. kava); gnathopod 2 propodus length 2.4× longer than broad (vs. propodus only 1.5× longer than broad in P. kava); pereopod 5 and pereopod 7 propodus distal part expanded and with 2 and 4 robust setae respectively (vs. pereopod 5 and pereopod 6 propodus distal part expanded and with 2 and 3 robust setae respectively in P. kava).</p><p>Pleonexes spencebatei sp. nov. can be differentiated from P. parakava by the following characteristics: sigmoidal-shaped male gnathopod 1 palm (vs. evenly convex in P. parakava); gnathopod 2 propodus length 2.4× longer than broad (vs. propodus only 1.4× longer than broad in P. parakava); pereopod 5 and pereopod 7 propodus distal part expanded and with 2 and 4 robust setae respectively (vs. pereopod 5 to pereopod 7 propodus distal part expanded and with 4 robust setae each in P. parakava).</p><p>Pleonexes spencebatei sp. nov. and P. nargessi are very close with both species having a sigmoidal shaped male gnathopod 1 palm. However, the male gnathopods of P. spencebatei sp. nov. are distinctly more elongate and more slender than those of P. nargessi . The propodus on the male gnathopod 2 is 2.2× as long as broad in P. spencebatei sp. nov., (vs. it is only 1.9× as long as broad in P. nargessi); male gnathopod 1, the propodus is narrow and broadest proximally (vs. is broad and widest medially in P. nargessi); telson is apically truncate and lacks apical tubercles (vs. narrowly convex apically and has tubercles in P. nargessi). Other differences noted between P. spencebatei sp. nov. and the figures of P. nargessi in Momtazi &amp; Maghsoudlou (2020), include the absence of a robust seta on peduncular article 1 of antenna 1 in P. spencebatei sp. nov. (vs. present in P. nargessi); antenna 2 flagellum is 0.9× as long as peduncular article 5 (0.8× in P. nargessi); the presence of a single seta only on the maxilla 1 inner plate in P. spencebatei sp. nov. (3 setae in P. nargessi); gnathopod 2 basis anterior margin bare and posterior margin with only 2 setae (both margins with few setae in P. nargessi) and basis of both pereopod 3 and pereopod 4 comparatively less setose (basis of both more setose in P. nargessi).</p></div>	https://treatment.plazi.org/id/03A73E01FFEFFFD4C8E1FA96FBE2F969	Public Domain	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.		MagnoliaPress via Plazi	Thacker, Dimple;Myers, Alan A.;Trivedi, Jigneshkumar N.	Thacker, Dimple, Myers, Alan A., Trivedi, Jigneshkumar N. (2026): A new species of the genus Pleonexes Spence Bate, 1857 (Senticaudata, Ampithoidae) from Gujarat State, India. Zootaxa 5748 (3): 419-428, DOI: 10.11646/zootaxa.5748.3.7, URL: https://doi.org/10.11646/zootaxa.5748.3.7
03A73E01FFE8FFD5C8E1F89EFC99FC77.text	03A73E01FFE8FFD5C8E1F89EFC99FC77.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Pleonexes Spence Bate 1857	<div><p>Identification key to Pleonexes species in the world (Modified from Souza-Filho &amp; Andrade, 2022)</p><p>1. Male gnathopod 2 palm of propodus incised, with thumb-like process........................................ 2 Male gnathopod 2 palm of propodus not incised.......................................................... 6</p><p>2. Telson with subacute apex............................................. Pleonexes divisura (Shoemaker, 1933) Telson with truncate or rounded apex.................................................................. 3</p><p>3. Male uropod 2 peduncle with minute distoventral process........................... Pleonexes kava (Myers, 1985) Male uropod 2 peduncle without distoventral process...................................................... 4</p><p>4. Male gnathopod 1 palm evenly convex....................................... Pleonexes parakava (Peart, 2007) Male gnathopod 1 palm sigmoidal shaped............................................................... 5</p><p>5. Male gnathopod 2 propodus 1.9× as long as broad................ Pleonexes nargessi Momtazi &amp; Maghsoudlou, 2020 Male gnathopod 2 propodus 2.2× as long as broad................................ Pleonexes spencebatei sp. nov.</p><p>6. Male gnathopod 2 palm not defined................................................................... 7 Male gnathopod 2 palm well defined by distinct angle or process........................................... 11</p><p>7. Telson with truncate apex........................................................................... 8 Telson with subacute apex.......................................................................... 9</p><p>8. Mandibular palp article ratio 5:9:6............................................ Pleonexes navosa (Myers, 1985) Mandibular palp article ratio 2:5:4................. Pleonexes suapensis (Correia, Guedes-Silva &amp; Souza-Filho, 2016)</p><p>9. Telson cusps very large, around 0.2× of the entire length of the telson............ Pleonexes poipu (J.L. Barnard, 1970) Telson cusps small, around 0.1× of the entire length of the telson........................................... 10</p><p>10. Antenna 1 subequal in length to antenna 2............................... Pleonexes kaneohe (J.L. Barnard, 1970) Antenna 1 shorter than antenna 2, reaching distal end of peduncle....... Pleonexes lowry Souza-Filho &amp; Andrade, 2022</p><p>11. Telson cusps very large, around 0.3× the entire length of the telson.......................................... 12 Telson cusps comparatively smaller, around 0.1–0.2× the entire length of the telson............................. 13</p><p>12. Male gnathopod 2 propodus subrectangular........................... Pleonexes gammaroides Spence Bate, 1856 Male gnathopod 2 propodus suboval........................................ Pleonexes helleri (Karaman, 1975)</p><p>13. Gnathopod 2 palm excavated........................................... Pleonexes maxillissius (Ledoyer, 1984) Gnathopod 2 palm not excavated..................................................................... 14</p><p>14. Gnathopod 2 propodus suboval...................................................................... 15 Gnathopod 2 propodus subrectangular................................................................ 16</p><p>15. Coxa 1 anteroventral corner slightly produced, antenna 1 peduncular article 1 and 2 densely setose................................................................................. Pleonexes auriculata (Rabindranath, 1972) Coxa 1 anteroventral corner produced, antenna 1 peduncular articles 1 and 2 poorly setose................................................................................................ Pleonexes rotunda (Peart, 2007)</p><p>16. Gnathopod 2 palm convex, palmar corner rounded........................... Pleonexes kulafi (J.L. Barnard, 1970) Gnathopod 2 palm almost straight, palmar corner square......................... Pleonexes meganae (Peart, 2007)</p></div>	https://treatment.plazi.org/id/03A73E01FFE8FFD5C8E1F89EFC99FC77	Public Domain	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.		MagnoliaPress via Plazi	Thacker, Dimple;Myers, Alan A.;Trivedi, Jigneshkumar N.	Thacker, Dimple, Myers, Alan A., Trivedi, Jigneshkumar N. (2026): A new species of the genus Pleonexes Spence Bate, 1857 (Senticaudata, Ampithoidae) from Gujarat State, India. Zootaxa 5748 (3): 419-428, DOI: 10.11646/zootaxa.5748.3.7, URL: https://doi.org/10.11646/zootaxa.5748.3.7
