Corallana mishrai, Anil & Bruce & Jayaraj, 2022

Anil, Pathan, Bruce, Niel L. & Jayaraj, K. A., 2022, A new species of Corallana Dana, 1852 (Crustacea: Isopoda: Corallanidae) from the Andaman Islands, northern Indian Ocean, Zootaxa 5087 (2), pp. 357-371 : 362-369

publication ID	https://doi.org/ 10.11646/zootaxa.5087.2.6
publication LSID	lsid:zoobank.org:pub:EC8ED2AB-376A-412C-9CD3-86F9EF0CB70F
DOI	https://doi.org/10.5281/zenodo.5824200
persistent identifier	https://treatment.plazi.org/id/292387D1-FFDF-F46C-FF59-FEAE06A1FB5E
treatment provided by	Plazi
scientific name	Corallana mishrai
status	sp. nov.

Treatment

Corallana mishrai View in CoL sp. nov.

( Figs 3–7 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 )

Material examined (all South Andaman, Andaman Islands)

Holotype. 1♂ (13.5 mm), stn. Kodiyaghat, 11°31′699′′N; 92°43′432′′E, intertidal (brackish reaches of creek), coll. Pathan Anil , 6 July 2018 (Reg. no. PUMB 3599 ).

Paratypes. 2♂ (12.0, 13.0 mm), 1♀ (11 mm), same data as holotype (Reg. no. PUMB 35100). 1♂ (12.3 mm), stn. Burmanallah, 11°33′261′′N; 92°43′963′′E, intertidal (brackish reaches of creek), coll. Pathan Anil, 7 July 2018 (Reg. no. PUMB 35101). 1♂ (13.0 mm), 1♀ (10.5 mm), stn. Chidiyatapu, 11°29′55′′N; 092°42′50′′ E, intertidal (brackish reaches of creek), coll. Pathan Anil, 10 July 2018 (Reg. no. PUMB 35102). 1♂ (13.4 mm), stan. Manjery, 11°58’33’’N; 92°66’67’’E, intertidal, coll. Pathan Anil, 12 July 2018 (Reg. no. PUMB 35103).

Description of male holotype ( Figs 3–7 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 )

Body 2.6 times as long as greatest width, widest at pereonite 5, lateral margins subparallel. Eyes separated by about 64% width of head; eye colour black. Pereon and coxae sparsely setose. Cephalon bearing 1 pair of tubercles between eyes, transverse row of 6 tubercles present on pereonite 1, and 4 small sub-lateral tubercles on posterior margin of pereonite 5. Pereonite 6 lateral margins drawn out into large posterior projecting lobes, 2 smaller submedial lobes bordering shallow dorsal concavity; inner two smaller straight sub-medial lobes posterior margins projecting. Pereonite 7 also with one pair of conspicuous tubercles on posterior margin. Pereonite 1 and coxae 2–3 each with posteroventral angle slightly rounded with partial oblique carina; 4–7 with partial oblique carinae and posteroventral angles progressively produced. Pleon with pleonite 1 concealed by pereonite 7; pleonites 2, 3 and 4 with lateral tubercles absent on posterior margins; lateral margins of pleonite 4 overlapping and concealing lateral margins of pleonite 5. Pleotelson anteriorly wider than long, length 0.76 greatest width, lateral margins bisinuate, terminating in bluntly rounded apex, both margins and apex setose, apex bearing 5 RS.

Antennula peduncular article 1 strongly expanded, projecting anteriorly, visible in dorsal view and inferior distal margin with three long setae; article 2 short, 0.25 length of article 1, superior medial margin with single short seta, distal margin with 3 plumose setae and single short seta; article 3 2.2 times as long as wide, 0.21 as long as article 2, superior medial margin with two short setae and inferior medial margin with two short setae; flagellum with 12 articles, extending to anterior of pereonite 1.

Antenna peduncle article 2 1.7 times as long as wide, 1.3 as long as article 1, superior margin with short setae; article 3 1.6 times as long as wide, 1.2 as long as article 2, superior distal margin with 3 long setae; article 4 2 times as long as wide, 2.8 times as long as article 3, superior margin with 5 short setae, single plumose seta, dorsal distal margin with single plumose seta and inferior margin with 4 short setae; article 5 2.4 times as long as wide, 3 times as long as article 4, superior distal margin with 2 simple short setae and inferior distal margin with single plumose seta; flagellum with 22 articles, extending to pereonite 3.

Frontal lamina conspicuous, 1.4 times as wide as long, with short straight (or very weakly convex) lateral margins, anterior margin forming strong acute median point; clypeus more than twice as broad as frontal lamina with lateral margins rounded and produced posteriorly to encompass labrum.

Mandible well developed with bidentate incisor and vestigial molar process; palp arising basally and just exceeding tip of mandible in length, article 2 2.3 times as long as articles 1 and 3 which are subequal; articles 2, 3 lateral distal margins with 8, 12 setae respectively.

Maxillula exopod hook-shaped terminating in single spine. Maxilla with 3 apical setae.

Maxilliped article 2 mesial distal angle with small setae, single long slender seta; article 3 longer than combined length of articles 4 and 5, mesial distal angle with small hair like setae, 5 long slender setae, laterodistal angle with single long slender seta; article 4 mesial distal angle with 3 short slender setae; article 5 apex with 4 setae.

Pereopod 1 basis 2.5 times as long as greatest width, superior margin with 2 plumose setae and many short setae, superior proximal dorsal margin with 3 plumose setae, distal margin with 3 long setae and inferior distal margin with 3 long setae; ischium 0.6 times as long as basis, superior distal margin with 3 long setae, inferior medial margin with 3 short setae and distal margin with 2 blunt spines, 4 short setae; merus superior distal margin with 3 long setae, inferior margin with 6 blunt spines, 7 long setae; carpus inferior distal margin with single spine and 2 long setae; propodus 2.9 times as long as wide, superior margin with 4 short setae, inferior margin with 2 spines, 4 long setae; dactylus 1.3 as long as propodus, superior distal margin with 3 short setae, inferior margin with single seta; dactylus without secondary unguis.

Pereopod 2 basis 2.9 times as long as greatest width, superior margin with 2 plumose setae and 7 short setae, superior dorsal surface with 4 plumose setae and many short setae, inferior margin with 8 long setae; ischium 0.9 times as long as basis, superior margin with 3 long, 1 short seta, inferior medial margin with 3 short setae and distal margin with 4 blunt spines, 3 long setae; merus superior distal margin with 3 long setae, inferior margin with 7 blunt spines, 5 long setae; carpus inferior distal margin with single spine, single long seta; propodus 3.2 times as long as wide, superior margin with 5 short, 1 long seta, inferior margin with 2 spines, 4 long setae; dactylus 1.5 as long as propodus, superior distal margin with 3 short setae, inferior margin with single seta; dactylus without secondary unguis. Pereopod 3 essentially similar to pereopod 2.

Pereopods 4 and 5 similar.

Pereopod 6 basis 2.6 times as long as greatest width, superior margin with single plumose seta, many short setae, superior dorsal surface with 3 plumose setae, 4 short setae and inferior margin with 8 short, 2 long setae; ischium 0.7 as long as basis, superior distal margin with 3 RS, inferior margin with 9 RS; merus 1.6 times as long as wide, 0.9 as long as ischium, superior distal margin with 2 biserrate setae, 2 RS, inferior distal margin with 5 RS; carpus 1.8 times as long as wide, 0.9 as long as ischium, superior medial margin with 5 short setae, distal margin with 3 biserrate setae, 2 RS, inferior distal margin with 6 RS; propodus 2.6 times as long as wide, 1.1 as long as ischium, superior margin with 6 short setae, inferior margin with 3 RS; dactylus 0.6 as long as propodus, superior distal margin with two short setae.

Pereopod 7 basis 2.9 times as long as greatest width, superior margin with 10 long setae, superior dorsal surface with 2 plumose setae, 5 short setae and inferior distal margin with 6 long setae; ischium 0.9 times as long as basis, superior distal margin with 2 biserrate setae, 2 RS, inferior margin with 8 RS, 3 short setae; merus 2.0 times as long as wide, 1.2 times as long as ischium, superior margin with 2 RS and 6 long setae, inferior margin with 6 RS, 4 long setae; carpus 1.9 times as long as wide, 1.0 times as long as ischium, superior medial margin with 5 long setae, distal margin with 3 uni-serrated setae, 4 biserrate setae and single RS, inferior margin with 4 RS, 3 long setae; propodus 3.0 times as long as wide, 1.4 times as long as ischium, superior distal margin with 4 short, 3 long setae, inferior margin with 5 RS; dactylus 0.8 times as long as propodus.

Pleopod 1 exopod 1.7 times as long as wide, lateral margin convex, distally narrowly rounded, mesial margin weakly convex, with PMS from distal one-third, with ~23 PMS; endopod 2.2 times as long as wide, distally subtruncate, lateral margin weakly concave, with PMS from distal one-third, mesial margin with PMS from distal one-third, endopod with ~14 PMS; peduncle 1.7 times as wide as long, mesial margin with 4 coupling setae, 2 plumose setae.

Pleopod 2 exopod with ~26 PMS, endopod with ~16 PMS; appendix masculina with parallel margins, 0.9 times as long as endopod, distally narrowly rounded. Pleopods 3–5 endopods without setae; pleopod 3 exopod with ~23 PMS; pleopod 4 exopod with ~21 PMS; pleopod 4 exopod with ~17 PMS. Pleopods 2–5 peduncle distolateral margin with prominent acute RS. Pleopods 3–5 exopods with incomplete transverse suture.

Uropodal exopod 7 times longer than greatest width, extending beyond endopod by one fourth of its length, lateral margin smooth, weakly convex with 3 RS and PMS along length, apex horizontal slightly rounded and mesial margin smooth, straight with 2 RS and PMS along length; endopod lateral margin slightly convex with 4 RS and PMS, apex forms a slightly obtuse angle with long simple setae, mesial margin weakly convex with 2 RS and PMS along length.

Female. Females differ from males in having a less setose body; tubercles absent from cephalon and pereonite 1; 2 small tubercles only on posterior margin of pereonite 5, 4 small tubercles present on posterior margin of pereonite 6; posterior margin with weak median dorsal concavity. Otherwise, apart from sexual characters, similar to the male.

Variation. Pleotelson (n = 8) always with 5 RS; uropod (all n = 16) exopod mesial margin with 2 RS (100%), lateral margin with 2–3 RS (3=93.8%, 2=6.2%); uropod endopod lateral margin with 4–5 RS (4=71.3%, 5=28.7%), mesial margin with 2 RS (100%).

Colour. Body light brown with brick-red coloured chromatophores on dorsal surface of pereon, pleon and telson.

Remarks. Corallana mishrai sp. nov. can be identified by the frontal lamina with short straight (or very weakly convex) lateral margins and the anterior margin forming a strong acute median point; pleotelson length 0.76 greatest width, with five robust setae on the posterior margin; the uropodal exopod is seven times longer than greatest width, extending beyond endopod by one fourth of its length; endopod lateral margin slightly convex with four robust setae and PMS, apex forms a slightly obtuse angle with long simple setae, mesial margin weakly convex with two robust setae and PMS; bidentate mandible; transverse row of six tubercles present on pereonite 1 and pleonites 2, 3 and 4 lacking lateral tubercles.

Corallana mishrai sp. nov. appears similar to C. nodosa Schioedte & Meinert, 1879 , from the Philippines, but Corallana mishrai sp. nov., differs to that species in having a frontal lamina with short straight (or very weakly convex) lateral margins and the anterior margin forming a strong acute median point (vs lateral margins that diverge anteriorly, with a single anterior margin that is strongly concave in C. nodosa , see Fig. 2F View FIGURE 2 ), a median transverse row of six tubercles on pereonite 1(vs absent on pereonite 1 in C. nodosa ).

Corallana mishrai sp. nov. differs from C. estuaria Jones et al. 1983 from Papua New Guinea, in the pleotelson apex bearing five robust setae (vs 11–12 robust setae in C. estuaria ), uropod endopod apex forming a slightly obtuse angle with six robust setae on lateral and mesial margins (vs acute angle with eight robust setae on outer and inner margins in C. estuaria ), uropod exopod seven times longer than greatest width, extending beyond endopod by one fourth of its length (vs six times longer than greatest width, extending beyond endopod by one third of its length in C. estuaria ), frontal lamina conspicuous, 8.0 times wider than long with large anterior acute medial point (vs inconspicuous, 6.0 times wider than long with small anterior medial point in C. estuaria ).

Based on frontal lamina shape Corallana mishrai sp. nov. differs from C. basalis Heller, 1868 ; C. brevipes Schioedte & Meinert, 1879 ; C. collaris Schioedte & Meinert, 1879 ; C. hirticauda ( Dana, 1853) ; Corallana sp. ( Delaney, 1989) ; C. furcilla ( Barnard, 1955) ; C. nodosa ( Schioedte & Meinert, 1879; Delaney, 1989); C. tridentata Jones Icely & Cragg, 1983 (see Fig. 2G View FIGURE 2 ); and presence of cephalic tubercles clearly distinguishes Corallana mishrai sp. nov. from C. hirsuta Schioedte & Meinert, 1879 .

Distribution. Known only from the type locality, South Andaman, Andaman Islands.

Etymology. This species is named in honour of eminent marine biologist Professor Dr. Jayant Kumar Mishra, Department of Ocean Studies and Marine Biology, Pondicherry University.