Porcellanella haigae Sankarankutty, 1963

Porcellanella haigae Sankarankutty, 1963

( Figs. 2C View Figure 2 , 5 View Figure 5 )

Porcellanella triloba : Miyake, 1943: 134, fig. 53 — Lieske and Myers, 2004: 338 (color photograph), fig. 9.

Porcellanella haigae Sankarankutty, 1963: 273 , fig. 1a–e [ type locality: Off Tuticorin in the Gulf of Mannar, intertidal and associated to sea pen]. — Haig, 1966: 61 — Nakasone and Miyake, 1972: 142, fig. 3A–H. — Haig, 1981: 288. — Haig, 1983: 287. — Haig, 1989: 99. — Werding and Hiller, 2007: 19 View Cited Treatment , fig. 18a–c. — Prakash et al., 2013b: 1517 (checklist). — Patel et al., 2022: 38 (checklist), 80 (checklist).

Material examined. 1 ovigerous female (4.5 × 3.4 mm) ( IO /SS/ANO/00157), Andaman Sea , off Great Nicobar Island, India, FOR/ V “Sagar Sampada” station 38818, 6.64°N 93.82°E, 56 m, chain dredge, 16.viii.2019, coll. V. P. Padate GoogleMaps .

Taxonomic remarks. Porcellanella haigae was originally described on the basis of one male and one female from the Gulf of Mannar and distinguished from Porcellanella triloba White, 1851 by the form of the carapace and cheliped merus and nature of the spines on the ambulatory dactyli ( Sankarankutty, 1963). The present specimen represents the second record of the species from India and the first record from the Andaman Sea. It agrees with the original description and a subsequent account by Nakasone and Miyake (1972) of P. haigae in the absence of mesiodistal lobe on the cheliped merus and the ambulatory dactyli each with third spine from the proximal end being largest among the flexor marginal spines.

Distribution. Red Sea, Seychelles, India, Philippines, Japan, Palau Islands; 18–60 m in bathymetric range ( Haig, 1989; Werding and Hiller, 2007; present study) ( Fig. 1 View Figure 1 ). Identification key to all the porcellanids known in the Indian EEZ

1. Chelipeds straight, directed anteriorly; carpus wider than long. Ambulatory dactyli triunguiculate ...... ........... Genus Pseudoporcellanella Sankarankutty, 1962 View in CoL ; monotypic, P. manoliensis Sankarankutty, 1962 View in CoL

– Chelipeds strongly bent at propodus-carpus articulation ................................................................................ 2

2. Antennal peduncle with articles 2–4 freely accessible to orbit ....................................................................... 3

– Antennal peduncle with articles 2–4 excluded from orbit by projection of article 1 appressed to anterior carapace margin ........................................................................................................................................................ 20

3. Pterygostomian f lap with posterior portion composed of 2 or more pieces separated from anterior portion by membranous interspaces (Genus Pachycheles Stimpson, 1858 View in CoL ) ................................................................. 4

– Pterygostomian flap composed of single, undivided plate ............................................................................... 7

4. Carapace without setae ............................................................................................................................................. 5

– Carapace distinctly setose ........................................................................................................................................ 6

5. Males with pair of gonopods on abdominal somite 2 ...................................... Pa. natalensis ( Krauss, 1843) View in CoL

– Males without gonopods ...................................................................... Pa. sculptus (H. Milne Edwards, 1837) View in CoL

6. Frontal margin of carapace without setal tufts, regions behind frontal margin with scattered setae. Rostrum broad, nearly transverse in dorsal view ................................................... Pa. pisoides ( Heller, 1865) View in CoL

– Frontal margin of carapace with tufts of short plumose setae and long, scattered, simple setae. Rostrum relatively narrow, bluntly triangular in dorsal view ................................... Pa. tomentosus Henderson, 1893 View in CoL

7. Carapace gastric region strongly elevated.Ambulatory legs subcylindrical (Genus Neopetrolisthes Miyake, 1937 View in CoL ) ............................................................................................................................................................................. 8

– Carapace with evenly f lattish or weakly convex dorsal surface. Ambulatory legs f lattened laterally (Genus Petrolisthes Stimpson, 1858 View in CoL ) .................................................................................................................................... 9

8. Carapace with strongly elevated protogastric ridges; supra-ocular spine present .........................................

........................................................................................................................... N. spinatus Osawa and Fujita, 2001 View in CoL – Carapace without elevated protogastric ridges; supra-ocular spine absent ......... N. maculatus View in CoL (H. Milne

Edwards, 1837)

9. Frontal margin of carapace tridentate, dorsal surface and extremities uneven, tuberculate. Cheliped carpus with 1 proximal tooth on flexor margin ...................................................... Pe. ornatus Paulson, 1875

– Frontal margin of carapace sinuously triangular or trilobate, dorsal surface and extremities with faint or distinct, short and long transverse ridges. Cheliped carpus usually with 2 or more teeth on flexor margin ......................................................................................................................................................................... 10

10. Carapace epibranchial spine present on each side ............................................................................................ 11 – Carapace epibranchial spine absent on each side ............................................................................................. 18

11. Inner orbital angles of carapace each produced into small spine ................... Pe. scabriculus ( Dana, 1852) – Inner orbital angles of carapace unarmed .......................................................................................................... 12 12. Lateral margin of carapace with some spines behind epibranchial spine ....... Pe. militaris ( Heller, 1862) – Lateral margin of carapace unarmed ................................................................................................................... 13

13. Supra-ocular spine of carapace present on each side ........................................... Pe. coccineus (Owen, 1839) – Supra-ocular spine of carapace absent on each side ......................................................................................... 14

14. Meri of ambulatory legs each with row of spines on extensor margin ......................................................... 15 – Meri of ambulatory legs without spines on extensor margins ....................................................................... 16

15. Carapace covered with numerous transverse ridges ................................... Pe. moluccensis (De Man, 1888) – Carapace covered with numerous, short plumose setae ................................... Pe. tomentosus ( Dana, 1852)

16. Cheliped carpus and chela with numerous, distinct transverse and oblique ridges ......................................

........................................................................................................................................... Pe. boscii (Audouin, 1826) – Cheliped carpus and chela without distinct transverse and oblique ridges ............................................... 17

17. Cheliped carpus with 3 broad teeth on dorso-flexor margin. P2 merus with small blunt distal spine on the lateral flexor margin; P2 carpus unarmed on extensor margin ...................................................................

.......................................................................................................... Pe. shanyingi Fang, Dong, Yang and Li, 2024 – Cheliped carpus usually with 4 or 5 broad teeth on dorso-f lexor margin. P2 merus with acute distal spine on the lateral flexor margin; P2 carpus with acute disto-extensor spine ....... Pe. lamarckii ( Leach, 1821)

18. Cheliped carpus with only 1 proximal tooth on dorso-flexor margin ........................ Pe. teres Melin, 1939 – Cheliped carpus usually with more than 3 teeth on dorso-flexor margin .................................................. 19

19. Gape of cheliped fingers with distinct tufts of plumose setae ............................. Pe. inermis ( Heller, 1862) – Gape of cheliped fingers without distinct pubescence ventrally ....................... Pe. rufescens ( Heller, 1861)

20. Carapace distinctly longer than wide (Genus Porcellanella White, 1851 ) ................................................... 21 – Carapace wider than long or slightly longer than wide ................................................................................... 22

21. Cheliped merus armed with distinct, subtriangular lobe on dorso-flexor margin distally. Dactyli of ambulatory legs each with proximal second tooth largest ......................................... Pc. triloba White, 1851

– Cheliped merus armed with indistinct lobe on dorso-flexor margin distally. Dactyli of ambulatory legs each with proximal third tooth largest ........................................................... Pc. haigae Sankarankutty, 1963

22. Dactyli of ambulatory legs straight, slender; f lexor margins without spines (Genus Raphidopus Stimpson,

1858) ........................................................................................................................................................................... 23 – Dactyli of ambulatory legs curved, stout; flexor margins with spines ......................................................... 24

23. Carapace branchial margins without spines. Cheliped carpus unarmed on extensor margin ................... ......................................................................................................................................... R. indicus Henderson, 1893

– Carapace branchial margins with spines. Cheliped carpus armed with spines on extensor margin ......... ....................................................................................................... R. dhritiae Mitra, Chowdhury and Bose, 2024

24. Frontal margin of carapace strongly deflexed ventrally, appearing straight or weakly sinuous in dorsal view. Dactyli of ambulatory legs each terminating in bifurcate claw (Genus Polyonyx Stimpson, 1858 )

...................................................................................................................................................................................... 25 – Frontal margin of carapace horizontal or down-tilted, appearing multilobed, broadly angular, or rounded in dorsal view. Dactyli of ambulatory legs each terminating in single claw ................................................ 29

25. Dactyli of ambulatory legs each with dorsal terminal claw smaller than ventral terminal claw .................

......................................................................................................................................... Po. loimicola Sankolli, 1965 View in CoL – Dactyli of ambulatory legs each with dorsal terminal claw longer or slenderer than ventral terminal claw .............................................................................................................................................................................. 26

26. Dorsal terminal claw of dactylus of each ambulatory leg subequal in length to ventral terminal claw .... ...................................................................................................................................................................................... 27

– Dorsal terminal claw of dactylus of each ambulatory leg distinctly longer than ventral terminal claw ... ...................................................................................................................................................................................... 28

27. Median frontal lobe of carapace triangular. Dactyli of ambulatory legs each with 2 spines on flexor margin ................................................................................................................... Po. biunguiculatus ( Dana, 1852)

– Median frontal lobe of carapace rounded. Dactyli of ambulatory legs each with only 1 spine on flexor margin ................................................................................................................................. Po. obesulus Miers, 1884

28. Chelae with dense plumose setae ......................................................................... Po. splendidus Sankolli, 1966 – Chelae at most with short setae ........................................................................ Po. hendersoni Southwell, 1909

29. Frontal margin of carapace broadly angular or rounded (Genus Ancylocheles Haig, 1978 ) ................... 30 – Frontal margin of carapace multilobed ............................................................................................................... 31

30. Median lobe of third thoracic sternite with strongly convex anterior margin. Third maxilliped merus with subrectangular lobe on flexor margin .................. A. peterngi Trivedi, Osawa and Vachhrajani, 2017

– Median lobe of third thoracic sternite with transverse anterior margin. Third maxilliped merus with rounded lobe on flexor margin ................................................................................. A. gravelei (Sankolli, 1966)

31. Dorsal surface of carapace areolate, regions well-defined (Genus Enosteoides Johnson, 1970 ). Article 1 of antennular peduncle with sharp spines on anterior margin. Cheliped carpus with minute denticles on proximal part of dorso-flexor margin ................................................................... E. ornatus ( Stimpson, 1858)

– Dorsal surface of carapace surface smooth or bearing fine striations .......................................................... 32

32. Carapace without hepatic spine, branchial margin unarmed behind epibranchial angle.Chelipeds subequal (Genus Porcellana Lamarck, 1801 ). Frontal margin of carapace with shallowly bifid median tooth, lateral frontal teeth narrower than median tooth and separated by broad V-shaped notch; epibranchial angle with 2 or 3 denticles. Cheliped carpus with 2 teeth and few smaller teeth on dorso-flexor margin .......... .................................................................................................................................................... Pi. persica Haig, 1966

– Carapace with hepatic spine, branchial margin with 1 or more spines behind epibranchial angle. Chelipeds unequal ....................................................................................................................................................................... 33

33. Frontal margin of carapace with median notch. Spination of chelipeds similar in both sexes (Genus Lissoporcellana Haig, 1978 ) .................................................................................................................................... 34

– Frontal margin of carapace without median notch. Spination of chelipeds more prominent in female than male (Genus Pisidia Leach, 1821 ) ......................................................................................................................... 35

34. Cheliped carpus with 3 spines on extensor margin ............................................ L. spinuligera ( Dana, 1853) – Cheliped carpus unarmed on extensor margin ............................................... L. quadrilobata ( Miers, 1884)

35. Rostrum with median lobe nearly as broad as lateral lobes. Cheliped carpus unarmed on dorso-flexor margin ............................................................................................................................ Pi. dehaanii ( Krauss, 1843)

– Rostrum with median lobe distinctly broader than lateral lobes. Cheliped carpus armed with spines on dorso-f lexor margin ................................................................................................... Pi. gordoni ( Johnson, 1970)