Holops pullomen Barahona-Segovia & Guzmán & Pañinao-Monsálvez 2021, sp. nov. Author Barahona-Segovia, Rodrigo M. Author Guzmán, Vicente Valdés Author Pañinao-Monsálvez, Laura text Zoological Studies 2021 2021-02-24 60 4 1 10 http://dx.doi.org/10.5281/zenodo.8055920 journal article 10.6620/ZS.2021.60-04 1810-522X PMC8292842 34322170 12823473 Epicepon indicum Nierstrasz & Brender à Brandis, 1931 ( Fig. 2 ) Epicepon indicum Nierstrasz & Brender à Brandis, 1931: 189–191, figs. 74–77; Dollfus et al. 1933: 76 [list]. Material examined : Female syntype ( 2.8 mm TL), parasitizing Tymolus sp. , Kei Islands, Indonesia , St. 56, 05°30'S , 132°51'E , 345 m , coll. T. Mortensen, Danish Expedition to the Kei Islands, 10 May 1922 (ZMUC CR-6788). Redescription : Female ( Fig. 2A–H ) length 2.8 mm ; maximum width (across pereomere 3) 1.3 mm ; head length 0.5 mm ; head width 0.7 mm ; pleon length 1.2 mm . Body linear (no asymmetry); all segments of body distinct ( Fig. 2A ). Head ovate, wider than long, frontal margin rounded medially. Frontal lamina relatively thin and extending beyond sides and frontal margin of head ( Fig. 2A ). Eyes lacking. Antennules and antennae with three and four articles each, respectively, distalmost article of antennule and two distalmost articles of antenna terminally setose ( Fig. 2B ). Barbula with one slender, distally rounded lateral projection on each side, middle region smooth with low lateral lobe ( Fig. 2E, G ). Maxilliped with prominent anterior segment, palp as low non-articulated projection with few distal setae, plectron triangular, short and broad ( Fig. 2G ). Pereon broadest across pereomere 3. Irregularly shaped tergal projections prominent on pereomeres 1–5 on right side, 2–4 on left side, ovate dorsolateral bosses on pereomeres 1–5 on right side, 2–3 on left side, thin coxal plates on both sides of pereomeres 1–5 ( Fig. 2A ). No mid-dorsal projections on any pereomeres. Oostegites enclosing brood pouch, oostegite 1 ( Fig. 2F ) with ovate anterior article, longer than posterior article, internal ridge smooth, posterior article rounded on lateral margin, extending to triangular point posteriorly. Pereopods subequal in structure, first four shorter than others ( Fig. 2A ). All pereopods with short, blunt dactyli, cylindrical propodi, carpi and meri fused in posterior pereopods ( Fig. 2C, D ). Fig. 2. Epicepon indicum Nierstrasz and Brender à Brandis, 1931, female syntype, ZMUC CR-6788 (A–H) and male syntype, CR-6788 (I–J). A, dorsal view. B, left antennule (A1) and antenna (A2). C, right pereopod 1. D, right pereopod 7. E, left side of barbula. F, right oostegite 1, internal view. G, right maxilliped, external view with outer projection of barbula (OB). H, pleon, ventral view showing uropods (Ur), fifth lateral plates (Lp5), exopod (Ex5) and endopod (En5). I, dorsal view. J, lateral view. Scale bars: B = 25 µm, C, D = 50 µm, E = 100 µm, F, G = 200 µm. A, H–J, from Nierstrasz and Brender à Brandis (1931); not to scale. Pleon with six segments, first five pleomeres each bearing five pairs of biramous pleopods and longer uniramous lateral plates, all margins with slight undulation but not digitate, surfaces smooth ( Fig. 2A, H ). Short digitiform endopods of pleopods approximately half as long as slender, distally tapering exopods ( Fig. 2H ). Terminal pleomere ending in uniramous uropods, similar to but slightly longer than fifth pleopodal exopods, surfaces smooth, margins with slight undulation but not digitate ( Fig. 2A, H ). Male ( Fig. 2I–J ) with all body regions and segments distinct. Head broadly rounded distally, extending posteriorly to rounded point overlapping approximately 1/3 length of pereomere 1 ( Fig. 2I ). Small, ovate dark eyes near posterolateral margins of head. Antennules and antennae not visible beyond margins of head in dorsal view. Pereomeres 2 – 4 subequal in width, other pereomeres only slightly narrower ( Fig. 2I ). All pereomeres tapered laterally, lacking mid-ventral tubercles. All pereopods subequal in structure and size ( Fig. 2J ). Pleon with six pleomeres, rounded laterally, each slightly narrower than preceding one ( Fig. 2I ). Mid-ventral tubercles lacking, pleopods as ventrolateral swelling on pleomeres 1–5 ( Fig. 2J ). Pleomere 6 without uropods, posterolaterally extended into two slender rami, each as long as rest of pleotelson; minute anal cone present distomedially ( Fig. 2I ). Range : Known only from the type locality, Kei Islands, Indonesia , 05°30'S , 132°51'E , 345 m depth. Remarks : The male syntype was incompletely described and figured by Nierstrasz & Brender à Brandis (1931) but is no longer in the vial with the female syntype and the above redescription of the male is therefore incomplete. The female syntype superficially appears to be immature based on the linear shape of the body but the oostegites are well-developed. The specific identity of the host is unknown as it was not retained with the parasites and the branchial chamber from which the parasites were extracted is not clear as the female is nearly linear. Epicepon belema n. sp. ( Figs. 3 , 4 ) urn:lsid:zoobank.org:act: 975C18A3-DE0C-4892-AEF0- D47ACEE92297 Material examined : Female holotype (2.0 mm TL including uropods), male allotype ( 1.1 mm TL) parasitizing right branchial chamber of Tymolus hirtipes Tan & Huang, 2000 , north of Panan, Pott (Phwoc) Island , Belep Islands, New Caledonia , Sta. CP172, 19°01'1.2"S , 163°16'1.2"E , 275–330 m , coll. MUSORSTOM 4, 17 Sept 1985 (ZRC 2016.0424). Description : Female ( Fig. 3 ) length 2.0 mm; maximum width (across pereomere 3) 1.4 mm ; head length 0.4 mm ; head width 0.7 mm ; pleon length 0.7 mm . Body slightly dextral; all segments of body distinct ( Fig. 3A ). Head oblong, wider than long, extending into rounded lateral projections, frontal margin entire medially. Frontal lamina thin and extending slightly beyond frontal margin of head ( Fig. 3A ). Small, irregular black eyes present mediolaterally ( Fig. 3A ). Antennules and antennae with two and three articles each, respectively, distalmost article of each terminally setose ( Fig. 3B ). Barbula with hook-shaped rounded lateral projection ( Fig. 3G ) and one rounded lobe, middle region smooth with low lateral lobe ( Fig. 3H ). Maxilliped with prominent anterior segment, palp as low non-articulated projection with few distal setae, plectron triangular, short and thin ( Fig. 3G ). Pereon broadest across pereomere 3. Irregularly shaped tergal projections prominent on pereomeres 1–5 on right side and 2–4 on left side, kidney-shaped dorsolateral bosses on both sides of pereomeres 1–4, thin coxal plates on both sides of pereomeres 1–4 ( Fig. 3A ). No mid-dorsal projections on any pereomeres. Oostegites enclosing brood pouch; oostegite 1 ( Fig. 3E, F ) with ovate anterior article, subequal in length to posterior article, internal ridge smooth, posterior article rounded distally (smaller posterior lobe is curled and has slight damage in holotype ). Pereopods subequal in structure and size ( Fig. 3A ). All pereopods with short, blunt dactyli, cylindrical propodi, carpi and meri distinct in all pereopods ( Fig. 3C, D ). Pleon with six segments, first five pleomeres each bearing pair of biramous pleopods and longer uniramous lateral plates, all margins with slight undulation but not digitate, surfaces smooth ( Fig. 3A, I ). Stub-like endopods of pleopods no more than half length of short, distally rounded exopods ( Fig. 3I, J ); exopods less than ½ length of lateral plates ( Fig. 3I, J ). Terminal pleomere ending in large uniramous uropods, similar to but longer than fifth pleopodal exopods, surfaces smooth, margins with slight undulation but not digitate ( Fig. 3A, I ). Male ( Fig. 4 ) length 1.1 mm ; maximum width (across pereomeres 3 and 4) 0.32 mm ; head length 0.2 mm ; head width 0.25 mm . All body regions and segments distinct ( Fig. 4A ). Head expanded distally, rounded posteriorly, distinctly separated from first pereomere ( Fig. 4A ). Large, irregular dark eyes near posterolateral margins of head. Antennules and antennae not visible beyond margins of head in dorsal view, of three articles each; both bearing setae on all articles ( Fig. 4C ). Pereomeres 3 and 4 subequal in width, other pereomeres only slightly narrower except pereomere 7 which is much narrower ( Fig. 4A ). All pereomeres rounded laterally, lacking mid-ventral tubercles. First pereopod larger than second, both larger than other five ( Fig. 4B, C, D ); all carpi with setae on distoventral ventral surface. Dactyli of pereopods 1 and 2 elongate, reaching distal margins of carpi ( Fig. 4B, C ), dactyli of pereopods 3–7 short, inserted into cup-like indentations at distoventral margin of propodi ( Fig. 4B, D ). Pleon with six pleomeres, rounded laterally, each slightly narrower than preceding one ( Fig. 4A, B ). Mid-ventral tubercles absent, distinct pleopods present laterally on pleomeres 1–5. Pleomere 6 without uropods, posterolaterally extended into two slender rami, each longer than rest of pleotelson, both tipped with short setae; anal cone present distomedially ( Fig. 4A, B ). Fig. 3. Epicepon belema , new species , female holotype, ZRC 2016.0424. A, dorsal view. B, right antennule (A1) and antenna (A2). C, left pereopod 1. D, left pereopod 7. E, left oostegite 1, external view. F, left oostegite 1, internal view. G, left maxilliped, external view (with outer lobe of barbula indicated with arrow). H, barbula (median lobes only). I, right side of pleon showing uropods (Ur), fourth and fifth lateral plates (Lp4, Lp5), fourth exopod (Ex4) and fourth endopod (En4). J, right pleomere 5 showing lateral plate (Lp), exopod (Ex) and endopod (En). Scale bars:A, E, F = 250 µm, B–D, J = 50 µm, G, I = 200 µm, H = 100 µm. Range : Known only from the type locality, north of Panan, Pott (Phwoc) Island , Belep Islands, New Caledonia , 275– 330 m . Fig. 4. Epicepon belema , new species , male allotype, ZRC 2016.0424. A, dorsal view. B, ventral view. C, left antennule (A1), antenna (A2), pereopod 1 and mouthparts. D, right pereopod 7 and pleomere 1 showing pleopod 1 (P1). E, pleomere 5 with pleopods (P5) and uropods (Ur). Scale bars: A, B = 250 µm, C–E = 50 µm. Remarks : The female of Epicepon belema n. sp. can be distinguished from those of the other two in the genus in having a total length less than 2 times the maximum width ( E . indicum with total length greater than 2 times the maximum width) and pleopodal endopods greater than 1/4 length of the exopods, exopods less than 1/2 length of lateral plates, and barbula without slender elongated lobes ( E . japonica with pleopodal endopods less than 1/4 length of the exopods, exopods greater than 1/2 length of lateral plates; barbula of E . indicum with one slender elongate lobe, barbula of E . japonica with two slender elongated lobes). Etymology : The specific name “ belema ” is both the name inhabitants of the Belep islands call themselves as well as the adjective used for things related to the Belep Islands; the name is used here as a noun in apposition.