identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
03B6878A275618495FAB2482CB6B2D9A.text	03B6878A275618495FAB2482CB6B2D9A.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Macrobrachium oblitus Carvalho & Grave 2026	<div><p>Macrobrachium oblitus sp. nov.</p><p>(Figs. 1–4)</p><p>Material examined. Holotype: ovigerous female (pocl 6.1 mm), Brazil: Mato Grosso, Porto Esperidião, Represa da Fazenda Pantanalzinho, 23.xi.1984, coll. Flavio &amp; Polo Nordeste Project (MNRJ 31807) . Paratypes: 2 ovigerous females (pocl 6.0, 6.6 mm), 10 males (pocl 3.4–4.2 mm), same data as holotype (MNRJ 5660) .</p><p>Description. Rostrum straight, with a slightly convex ventral margin, shorter than carapace, surpassing antennular peduncle and reaching distal margin of scaphocerite; dorsal margin armed with 7–9 teeth, with 1 postorbital tooth and sometimes with subapical tooth; ventral margin with 3 or 4 teeth and continuous double row of plumose setae (Fig. 1A, H–I); carapace smooth, with both antennal and hepatic teeth present (Fig. 1C, D).</p><p>Abdomen with pleura of first to fifth somites ventrally rounded (Fig. 1B). Sixth abdominal somite 0.7–0.8 times length of telson, bearing acute tooth on posteroventral angle. Telson with 2 pairs of dorsal cuspidate setae, both positioned in distal half; posterior margin with acute median projection bearing 2 pairs of cuspidate setae, inner pair overreaching the telson tip, and 2–4 plumose setae (Fig. 2B, C).</p><p>Antennular basal article with straight anterior margin, lacking projections; stylocerite acute, reaching approximately half of length of basal article; inner margin of basal article straight; transverse row of setae present on dorsolateral surface (Fig. 1F). Second peduncular article shorter than distal article, with slightly convex margins. External flagellum bifurcated, external ramus approximately three times longer than internal ramus, with 4–7 fused articles. Internal flagellum simple, shorter than external flagellum. Antenna with scaphocerite surpassing the antennular peduncle, not overreaching rostrum apex, external margin straight, bearing distolateral tooth; internal margin slightly convex; anterior margin rounded, with the apex closer to inner margin (Fig. 1G).</p><p>Mouthparts typical for genus. Mandible with tricuspid incisor lobe and molar lobe bearing 4 rounded processes; mandibular palp absent (Fig. 2D). Epipod of first maxilliped with 2 lobes completely fused, with triangular anterior lobe elongated anteriorly.</p><p>First pereiopod overreaching scaphocerite by tip of chelae, non-heterochelous; dactylus about as long as length of palm; carpus 2 times length of chela, 1.2 times length to merus, with a distal row of setae (Fig. 3A). Second pereiopod overreaching scaphocerite by 1/5 of propodus, non-heterochelous; dactylus 1.0 (female) to 1.2 (male) times length of palm; fixed and movable fingers with scattered setae, cutting margins entire, lacking teeth and hiatus; carpus 1.1–1.3 times length of chela and 1.4–1.6 times length of merus (Fig. 3B–C, 4D–E).</p><p>Third and fourth pereiopods over-reaching scaphocerite by length of dactylus when fully extended; fifth pereiopod over-reaching scaphocerite by tip of dactylus. Third to fifth pereiopods with row of simple setae at dorsodistal extremity of propodus and ventrodistal row of setae consisting of pair of cuspidate setae, with additional 4–6 cuspidate setae distributed along ventral surface. Propodus/dactylus ratio: third pereiopod = 2.0–2.6, fourth pereiopod = 2.2–2.6, fifth pereiopod = 2.5–3.3 (Fig. 3D–G).</p><p>First pleopod with endopod approximately half length of exopod, lacking appendix interna in males (Fig. 4A). Male second pleopod with appendix masculina slender, about 0.75 times length of endopod (Fig. 4B) and 1.8 times length of appendix interna, with setae along its length (Fig. 4C).</p><p>Uropods surpassing distal margin of telson by 0.21 of their length; protopodite unarmed; exopod with straight lateral margin ending in acute distolateral tooth, lacking mobile distolateral cuspidate setae (Fig. 2A).</p><p>Etymology. The specific name oblitus is Latin, meaning "forgotten", alluding to the fact that the type series was collected in 1984 and, since then, remained unnoticed in the collections of the Museu Nacional in Rio de Janeiro.</p><p>Fecundity. Ovigerous female (paratype) with 14 eggs, non-eyed, approximately 1.3 × 0.9 mm in size.</p><p>Remarks. In all specimens examined, a mandibular palp is absent, although in one female a reduced palp was present on one side. Morphologically, the new species is very similar to M. bouvieri, which occurs in the same drainage basin. Owing to the preservation state of the specimens, no viable DNA could be extracted to determine this assumed phylogenetic position. It can, however, be easily distinguished from M. bouvieri by the presence of continuous double row of plumose setae on the ventral margin of the rostrum (versus a single row with gaps over the teeth in M. bouvieri), and the rostrum being more robust (versus more slender in M. bouvieri, compare Figs. 1A, C with Holthuis 1952: pl. 32). Further morphological differences are as follows: 1) in females of M. bouvieri, first pereiopod does not reach the distal margin of the scaphocerite (versus in M. oblitus sp. nov. the tip of the chela of first pereiopod surpasses it); 2) males of M. bouvieri possess longer fingers on the second chela, with a finger length of 1.5 times the palm length (versus 1.3 times in M. oblitus sp. nov.); and 3) M. bouvieri has a shorter carpus (1.2 times the length of the merus) and a shorter ischium (0.5 times the length of the carpus) (versus 1.4 and 0.7, respectively in M. oblitus sp. nov.).</p></div>	https://treatment.plazi.org/id/03B6878A275618495FAB2482CB6B2D9A	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	Carvalho, Fabrício Lopes;Grave, Sammy De	Carvalho, Fabrício Lopes, Grave, Sammy De (2026): A further novel species of Macrobrachium from Brazil (Decapoda, Palaemonidae), lacking a mandibular palp. Zootaxa 5759 (2): 185-192, DOI: 10.11646/zootaxa.5759.2.6, URL: https://doi.org/10.11646/zootaxa.5759.2.6
