Portunus segnis ( Forskål, 1775 )

Lai, Joelle C. Y., Ng, Peter K. L. & Davie, Peter J. F., 2010, A Revision Of The Portunus Pelagicus (Linnaeus, 1758) Species Complex (Crustacea: Brachyura: Portunidae), With The Recognition Of Four Species, Raffles Bulletin of Zoology 58 (2), pp. 199-237 : 215-218

Portunus segnis ( Forskål, 1775)

( Figs. 6B , 7B , 11 , 12 , 13 , 14 , 20B , 21B , 22B , 23B, 23F , 24B )

Cancer segnis Forskål, 1775: 18 , 91.

Cancer pelagicus Forskål, 1775: 89 .

Crabes-nageurs Savigny, 1826: Pl. 3, Fig. 1. 1–4 .

Portunus mauritianus Ward, 1942: 79 , Pl. 5 Fig. 5 .

Portunus trituberculatus – Stephenson & Rees, 1967b: 51–53 (in part, material from the Red Sea) [not P. trituberculatus Miers, 1876 ].

Lupa pelagica – Heller, 1861: 355 (part); Barnard, 1950: 152–154 Fig. 27b; Fourmanoir, 1954: 7, Fig. 7 .

Neptunus (Neptunus) pelagicus – Parisi, 1916: 171 (part); Stephensen, 1946: 124, 125, Fig. 26E; Hashmi, 1963a: 239; Hashmi, 1963b: 115, 117, 118.

Portunus (Portunus) pelagicus – Audouin, 1826: 83; 1827: 261; Tirmizi & Kazmi, 1983: 369; Ng et al., 2008: 152.

Neptunus pelagicus – Hoffmann, 1874: 7, 8; Paul’son 1875: 61; De Man, 1888: 328; Nobili, 1906: 190; Klunzinger, 1913: 336 Pl. 7: Fig. 17 ; Kohli, 1921: 85; Monod, 1930: 138,140, Fig. 6 ; 1938: 116; Gruvel, 1936: 50, 51, 71, 86, 94, 192, 195, 207, 215; Pretzmann, 1971: 471; Chandy, 1973: 402; Khan, 1975: 377 (list), 379–381, 390 (key), Fig. 2 , Pl. 1.

Portunus pelagicus – Crosnier, 1962: 43–45, Figs. 58, 61, 67; Guinot, 1962: 10; Heath, 1973: 2 (key), 13, Fig. 4b ; Pretzmann, 1971: 47; Ramadan & Dowidar, 1972: 132; Khan & Ahmed, 1975: 77; Mustaquim & Rabbani, 1976: 163; Basson et al., 1977: 224, 227, 231, 235, 250, 256; Kensley, 1981: 42 (list); Titgen, 1982: 118–120, 250 (list); Jones, 1986: 161, Pl. 47; Tirmizi & Kazmi, 1996: 18-21; Bahmani, 1997: 2, 6, 8, 9, 12; Hornby, 1997: 75; Carpenter et al., 1997: 38; Apel & Spiridonov, 1998: 279 (key), 300–303, Pls. 10, 11; Neumann & Spiridonov, 1999: 21; Vannini & Innocenti, 2000: 266, Figs. 18 , 23 , 76; Galil et al., 2002: 114; Corsini-Foka et al., 2004: 83.

Portunus (Portunus) segnis – Ng et al., 2008: 152.

Portunus pelagicus or P. segnis – Guinot & Cleva, 2009: 70, Pl. 3, Fig. 1 .

Material examined. – Neotype of Cancer segnis Forskål, 1775 (here designated); 1 male ( SMF 3679) (144.4 × 70.1 mm), Red Sea, Egyptian coast, probably southern Gulf of Suez, coll. Dr E. Bannwarth, 1912. Others: BAHRAIN: 1 male (113.1 × 49.8 mm), 1 female (103.1 × 46.0 mm) ( SMF 24424), from fisherman’s nets (BRN-02). ISRAEL: 3 males (largest 147.2 × 66.8 mm), 1 female (143.3 × 62 mm) ( ZRC 2007.225), off Ashjod, trawled by trawler MOTI, 12–14 fathoms, coll. B. Galil, 5 Dec.2003; 4 males (largest 141.3 × 66.9 mm), 9 females (154.8 × 72.5 mm) ( ZRC 2007.226) off Haifa, coll. B. Galil, 2005; 1 male (134.5 × 62.6mm) ( ZRC 2007.226), Mediterranean Coast. KENYA: 1 male ( MZUF C898), Gazi, coll. M. Vannini, Dec.1997. KUWAIT: 1 male (56.8 × 25.2 mm) ( NHM 1978.200), Khiran, Kuwait coast, coll. M. N. Mashmoom. MADAGASCAR: 8 males (largest 140.1 × 62.3 mm), 5 females (largest 153.2 × 69.4 mm), 6 juvs. ( ZRC 2007.220), Belaza Tulear, coll. H. H. Tan, Jan.2004; 1 male (90.9 × 40.8 mm), 1 female (116.2 × 52.3 mm) ( RMNH 47694), market at Morondava, west coast, coll. C. C. J. Jongkino, 11 Jan.1997; 1 juv. male (CL 24.37 mm) ( MNHN 844), Nosy Be, coll. A. Crosnier, 2 May 1961. MEDITERRANEAN SEA: 1 male (109.1 × 50.9 mm), 1 female (99.4 × 43.9 mm) ( MNHN B12284), Gulf of Terente, coll. Perenzan, 1969. MOZAMBIQUE: 4 juv. males (largest 37.2 × 21.7 mm), 3 juv. females (largest 45.4 × 26.7 mm) ( NHM 1951.9.13.416), Inyack Bay, Inhaca, Delagoa Bay (present day Maputo Bay), coll. O. S. Tattersall; 2 males, 1 female (126.6 × 60.00 mm) ( ZRC 2007.230), Maputo Bay, coll. P. Clark, 2004. PAKISTAN: 5 males (largest 156.2 × 74.2 mm), 22 females ( ZRC 2006.70), Karachi, coll. Q. B. Kazmi, Sep.2005; 1 juv. male (37.0 × 21.6 mm) ( SMF 21626), Korung Creek, Indus Delta, Sindh, coll. G. Pillen. PERSIAN GULF: 1 female (77.6 × 35.6 mm) ( NHM 88.25), coll. Kurachee Museum. RED SEA; 4 males ( SMF 10693) (94.9 × 43.1 to 115.5 × 55.1 mm), Jeddah Fish Market, Saudi Arabia, Red Sea, W. John, 20 Aug.1982; 1 male (114.5 × 53.4 mm) ( MNHN B6032), coll. 1929; 1 juv. female (70.2 × 39.3 mm) ( NHM), El Tor Presed, coll. Major Macdonald, 4 Sep.1966; 2 females (larger 72.2 × 40.4 mm) ( NHM), Gulf of Ilat, Aryab, coll. F. Day. SAUDI ARABIA: 5 male, 1 female (48.2 × 21.6 mm) ( NHM), Jedda, coll. A. C. Trott; 1 female (106.9 × 62.1 mm) ( SMF 24427), Jubail Marine Wildlife Sanctuary Al-Jubayl, W. Qurma Island, PTL-01 (27º07.090'N 49º27.300'E) sand/mud bottom, coll. M. Apel, 4 Dec.1991; 2 females (larger 132.7 × 60.6 mm) ( SMF 24430), Eastern, N. Jubail (27°25.410'N 049°16.010'E), sandy bottom, coll. M. Apel, 26 Nov.1991; 2 males (larger 56.4 × 25.7 mm), 2 females (larger 80.5 × 35.0 mm) ( SMF 24417), Eastern, Ras Az-Zawr (27°26.000'N 49°17.000'E) sublittoral sand flats, coll. M. Apel, 17 May 1995; 1 juv. male (31.7 × 15.0 mm), 1 juv. female (32.4 × 15.3 mm) ( SMF 24418), Eastern Ras Az-Zawr (27°26.000'N 49°17.000'E), beachrocks and sand, coll. M. Apel, 17 May 1995; 1 male (130.7 × 59.5 mm) ( SMF 24428), Eastern Jubail Marine Wildlife Sanctuary, N. Al-Jubayl, W. Jinna Island, PTL-04 (27°21.490'N 49°14.200'E) on rock and sand, coll. M. Apel, 28 Nov.1991; 1 male (95.9 × 43.0 mm) ( SMF 24429), Eastern Jubail Marine Wildlife Sanctuary, N. Al-Jubail, SW bank of Dauhat al Musallamiya, PTL-07 (27°23.330'N 49°10.150'E) on rock and mud, coll. M. Apel, 10 Dec.1991. SOMALIA: 1 male (117.2 × 51.9 mm), 1 female ( MZUF C811), Gresira, coll. M Vannini, Nov.-Dec.1976; 1 male (76.9 × 34.4 mm) ( MZUF C2672), 2 males (larger 127.8 × 58.3 mm), 4 females (135.8 × 61.2 mm) ( MZUF C2673), Sar Vaule, coll. M. Vannini, 1976; 1 juv. male (38.9 × 18 mm), 1 male (113.8 × 51.7 mm) ( NHM 1950.8.851), Zeilah, coll. A. Fraser-Bronner; 1 male (114.5 × 53.5 mm) ( MZUF C890), Mida Creek, Kenya, coll. M. Vannini, 1991; 2 females (94.1 × 43.7; 122.4 × 53.9 (ovig.) mm), 2 males (68.1 × 33.1; 84.3 × 38.2 mm) ( MZUF C890), Mtwapa, Mombasa, Kenya, coll. M. Vannini, Nov.–Dec.1993. SOUTH AFRICA: 1 male ( NHM 1917.6.19.37), Durban Bay, Natal, from Durban Bay Natal Government Museum, coll. F. Toppin, Mar.1905; 1 male (168.8 × 75.8mm) ( ZRC), coll. Institute of Aquatic Biodiversity, South Africa, Nov.2006. SUDAN: 1 male (newly moulted) ( SMF 24487), Küsta ca. 8 km Port Sudan, SAN-53, in Avicennia marina mangrove, coll. M. Apel, 23 Mar.1991. GULF OF SUEZ: 2 females (larger 130.5 × 60.1 mm) ( MNHN B6031), from SS Al Sayad, Station II, 1928. SYRIA: 1 male (144.7 × 68.0 mm), 2 females (larger 158.4 × 75.4 mm) ( SMF 8768), fish market, Latakia, coll. R. Kinzelbach, 31 Aug.1978. UNITED ARAB EMIRATES: 2 males (larger 119.9 × 54.4 mm), 3 females (largest 125.7 × 57.9 mm) ( ZRC 2007.224), Abu Dhabi, market facing Oman coast, coll. L. W. H. Tan, 26 Mar.2004, 2 juv. males (larger 48.3 × 21.8 mm) ( NHM 1999.68- 69), Trucial Coast, Abu Dhabi, coll. D. J. J. Kinsman, Imperial College; 1 juv. male (28.4 × 13.3 mm) ( NHM 1966.10.4.23), Khor al Bazam PS/34, Trucial Coast, Abu Dhabi, coll. Imperial College; 1 damaged female (58.0 × 26.5 mm) ( NHM 1966.10.4.22), Khor al Bazam, PG/B/449, Trucial Coast Abu Dhab, coll. Imperial College; 1 male ( SMF 24422), mangroves of Umm al Qaiwai, UAE 95-29 (25°35.000'N 55°34.000'E), 0-1m around small islands, Khor al Beidah, coll. M. Apel, 9 Jul.1995. OMAN: 2 females (larger 38.4 × 86.1 mm), 2 males (larger 37.7 × 83.2 mm) ( UF 7745), south end of Bar al Hikman peninsula, silty pebbly sand spit, coll. U. Bonito et al., 24 Jan.2005. MAURITIUS: 1 male (carapace width 170.0 mm, side of carapace damaged) ( MPL MAU-231) (damaged) (holotype of Portunus mauritianus Ward, 1942 ).

Type material. – The holotype of Forskål (1775) from Djedah (present day: Jeddah) in the Red Sea is lost, and a neotype for Cancer segnis is thus necessary to stabilise the nomenclature of this species .

We have selected a specimen collected from the original locality, a male ( SMF 3679 ) (144.4 × 70.1 mm), as the neotype .

Diagnosis. – Carapace width 2.2–2.3 times wider than long, median frontal teeth minute or obsolete, usually inconspicuous, appearing confluent or with wide gap between lateral median teeth, except sometimes in larger individuals (carapace width> 140 mm). Compared with adult male P. pelagicus , carapace regions relatively poorly defined, branchial regions not as swollen compared with P. pelagicus . Chelipeds narrow, elongated, merus length of adult males maximum 4.5 times longer than wide; most specimens with shorter, stouter chelipeds than P. pelagicus ; anterior margin of merus of cheliped usually with 3 spines. Ambulatory legs relatively more elongated, slender, merus of 4 th pereiopod 3.3–4.4 (median 3.6) longer than wide ( Fig. 21B ). Natatorial paddle elongate oval, obtusely angled distally, similar to P. pelagicus . Sixth male abdominal somite relatively shorter, less tapering ( Fig. 22B ). Base of G1 with slight basal spur ( Fig. 20B ). Largest specimen known is a female from Syria, 158.4 × 75.4 mm) (SMF 8768).

Life colours ( Figs. 6B , 7B , 14 ). – Males with dark olive green blue carapace with many pale white spots on surface particularly posteriorly and anterolaterally; spots do not tend to merge to form reticulating bands, however, such banding if present is typically thinner than in P. pelagicus . Females similar in pattern to male except that tips of chelipeds are red tinged with a brownish red instead of blue tinged with deep rust red.

by Forskål with the Latin name “ segnis ”. The presence of a white tip at the apex of the cheliped (Chelae viridi-caeruleae, apice albae), and the presence of a blue green spine with a red tip near the carpus (ad basin juxta carpum superne spina valida, conica, caerulea apice ferruginea) is peculiar — the P. pelagicus -complex conversely have red tips to the chelipeds and white tipped carpal spines. However, Forskål’s description of a dark green blue carapace with white cloud like markings (color superne obscure-viridis, nebulosus) does not fit any other portunid known from the Arabian Gulf other than P. pelagicus sensu lato (Apel & Spiridonov, 1998). This description matches the illustration of “Crabes-nageurs” presented in Savigny (1826: Pl. 3, Fig. 1. 1–4 ) (reproduced as Fig. 12 , from Guinot & Cleva, 2009: 70, Pl. 1, Fig. 3 ) and may explain some of his observations. The name “ Cancer segnis ” has not been used or discussed since its description. Unfortunately, Forskål’s voyage ended with his premature death and the type specimen which ought to have been sent to Denmark was never located (for an historical account of the Danish expedition to “Arabia Felix” see Nielsen, 1993; Wolff, 1999). Interestingly, Forskål (1775) referred to C. pelagicus on page 89 before describing the new species, C. Remarks. – Forskål (1775) described Cancer segnis from material collected from Jeddah, on the Red Sea coast of Saudi Arabia. His description is as follows: “ Cancer segnis ; brachyurus; thoracae laevi, utroque latere novem-dentato; fronte quatuor-dentata. Descr. Transverse-ovalis: latitudine spithamae, sed longitudine inferior. Color superne obscureviridis, nebulosus; subtus albidus. Antennae setaceae, nigrae, breves. In fronte spinae 4, inter oculos erectae, obtusiusculae: sub quovis oculo una validior. Oculorum pedicelli teretes, virides, oculi hemisphaerici; nitentes, obscuro-rubri, maculis albis: profunde inserti. Chelae viridi-caeruleae, apice albae: in forficis latere interiore una series callorum in singulo digito; in chela superne post basin pollicis spinae duae, contiguae, antrorsum spectantes: ad basin juxta carpum superne spina valida, conica, caerulea apice ferruginea, Praeterea nullae in chelis spinae; fed duae in carpis extrorsum, una introrsum, longior, fortior, Femora depressa, ob-cuneata, Secundum tertium par pedum subteres, versus apicem compressum, police nullo, leave, digito subulato. Quartum par longe crassius, articulis duobus postremis compressissimis, membranaceis, dilatatis, ovatis, margine ciliates. Cauda lata, albida, fusco-rivulata. In Mari rubro. Tarde procedit in aqua.”

Forskål’s description is relatively detailed for its time, and generally fits P. pelagicu s sensu lato. While there are some discrepancies, there does not seem to be any other likely candidate amongst the Red Sea fauna. Interestingly, most live portunids are active and aggressive, not “slow” as implied segnis on page 91. As there is marked sexual dimorphism in the species, perhaps like Herbst, Forskål (1775) had mistaken males and females as different species (see discussion for P. reticulatus ), and inadvertently established C. segnis for one sex. Another consideration is that his account is published posthumously and was most likely based on his field notes. Thus, it may also be possible that errors in description could have been the result of wrong interpretations of his notes or errors in typesetting. In any case, P. segnis is restricted to the West Indian Ocean (Red Sea and African coast) and differs from P. pelagicus of eastern Asia both morphologically and genetically.

Portunus mauritianus Ward, 1942 , was described from Mauritius, southwest Indian Ocean. From Ward’s (1942) description, it is apparent that what he conceived to be the true “ P. pelagicus ” was the Australian species, P. armatus . Consequently, he was correct in recognising the Mauritius material as a separate species. Portunus armatus has more clearly defined carapace granulation, sharper teeth and spines on the frontal and anterior margins, a differently shaped natatorial paddle, as well as four spines on the anterior margin of the merus of the cheliped versus three in P. mauritianus . The holotype of P. mauritianus is housed in the Mauritius Institute, but the specimen is badly damaged and all trace of colour patterning has been lost ( Fig. 11 ). Examination of photographs of the holotype from different angles shows it to be distinct from P. armatus , but its poor condition and broken carapace make it difficult to clearly separate it from P. pelagicus and P. reticulatus . Unlike typical P. segnis , the holotype has two distinct median teeth, but the specimen is large and larger specimens of P. segnis are also known to have prominent median teeth. Attempts were made to collect topotypes of P. mauritianus for further morphological and genetic study. However, the species is apparently uncommon in Mauritius (C. Michel, pers. comm.) and no specimens were collected. Anecdotal evidence also suggests that at least some P. pelagicus sensu lato sold in Mauritius may be imported from Mozambique or Madagascar although this could not be verified with actual collected material in the present study. Nevertheless, from the recent photographs we have of the holotype ( Fig. 11 ) and Ward’s figures of the chelipeds and gross morphology, along with the fact that only P. segnis is otherwise known from the western Indian Ocean, it is likely that P. mauritianus is a subjective junior synonym of P. segnis .

Stephenson & Rees (1967b) recorded one male and three female specimens of P. trituberculatus from the Red Sea, but Stephenson (1976) later clarified that this was a mistake and that the species attributed to P. trituberculatus was in fact P. pelagicus (= P. segnis in present study). The figure by Stephenson & Rees (1967b: Fig.17a, b ) compares “ P. trituberculatus ” from the Red Sea with P. pelagicus from the Philippines. It is possible that they used the absence of median frontal teeth in the Red Sea material to distinguish between the two species. When viewed dorsally, the lack of median frontal teeth coupled with the projection of the epistomial spine along the underside of the frontal margin gives the illusion of three teeth along the frontal margin and this was presumably the reason for their misidentification as P. trituberculatus .

Habitat. – Under rocks and in rock pools, on sandy or muddy substrate, intertidal to 55 m ( Galil et al., 2002). Common in fish landings in Pakistan (Tirmizi & Kazmi, 1996).

Distribution. – Western Indian Ocean, from Pakistan westwards to the Arabian Gulf, and extending to the east coast of South Africa, Mozambique, Madagascar and Mauritius. It has also entered eastern Mediterranean Sea, as a Lessepsian migrant through the Suez Canal ( Ekman, 1967; Ozcan et al., 2005; Yokes et al., 2007) and become established as far north as the northern Tyrrhenian Sea ( Crocetta, 2006).

Figures

Fig. 6. Live colours of males. A, Portunus pelagicus (Linnaeus, 1758) (142.7 × 67.1mm) (ZRC 2007.0235), Pulau Tekong, Singapore; B, Portunus segnis (Forskål, 1775) (140.1 × 62.3mm) (ZRC 2007.0220), Tulear, Madagascar (photograph: H. H. Tan); C, Portunus reticulatus (Herbst, 1799) (132.2 × 59.8mm) (ZRC 2007.0223), Chennai, India (photograph: Z. Jaafar); D, Portunus armatus (A. Milne-Edwards, 1861) (no specimen, photograph only) Brisbane, Queensland (photograph: P. J. F. Davie).

Fig. 7. Live colours of females. A, Portunus pelagicus (Linnaeus, 1758) (142.7 × 67.1mm) (ZRC 2007.0235), Pulau Tekong, Singapore; B, Portunus segnis (Forskål, 1775) (124.3 × 53.4mm) (ZRC 2007.0220), Madagascar, Tulear (photograph: H. H. Tan); C, Portunus reticulatus (Herbst, 1794) (132.2 × 59.8mm) (ZRC 2007.0223), Chennai, India (photograph: Z. Jaafar); D, Portunus armatus (A. Milne-Edwards 1861) (133.2 × 64.2 mm) (ZRC 2007.0232), Nelson Bay, New South Wales, Australia (photograph: S. Ahyong).

Fig. 11. Portunus mauritianus Ward, 1942. A, holotype male (carapace width 170.0 mm) (MPL MAU-231) (after Ward, 1942); B, present condition of specimen showing damaged carapace.

Fig. 12. Portunus segnis (Forskål, 1775) (photograph based on a re-edition of the plates of Savigny by Institut d’Orient (1988), © Institut d’Orient/Naguib-Michel Sidhom, in Guinot & Cleva, 2009), Red Sea.

Fig.13. Portunus segnis (Forskål, 1775), neotype male (144.4 × 70.1 mm) (SMF 3679), Red Sea, Egyptian coast (photograph: M. Türkay, SMF).

Fig. 14. Portunus segnis (Forskål, 1775) (specimen not preserved), Doha fish market, Qatar, (photograph: H. Q. Ng).

Fig. 20. G1 and distal part of G1 structures. A, Portunus pelagicus (110.7 × 48.8 mm) (RMNH D384); B, P. segnis (147.2 × 66.8 mm) (ZRC 2007.225); C, P. reticulatus (138.5 × 60.7 mm) (ZRC 2007.222); D, P. armatus (150.8 × 73.6 mm) (ZRC 2007.232). Scale = 1 mm.

Fig. 21. Fourth and fifth pereiopod merus, carpus, dactylus. A, Portunus pelagicus (152.9 × 68.0 mm) (ZRC 2007.233); B, P. segnis (134.5 × 62.6 mm) (ZRC 2007.226); C, P. reticulatus (138.5 × 60.7 mm) (ZRC 2007.222); D, P. armatus (133.0 × 66.0 mm) (ZRC 2007.229).

Fig. 22. Male abdominal somites. A, Portunus pelagicus (152.9 × 68.0 mm) (ZRC 2007.233); B, P. segnis (134.5 × 62.6 mm) (ZRC 2007.226); C, P. reticulatus (138.5 × 60.7 mm) (ZRC 2007.222); D, P. armatus (133.0 × 66.0 mm) (ZRC 2007.229).

Fig. 23. Frontal margin and merus of left cheliped A, E, Portunus pelagicus (152.9 × 68.0 mm) (ZRC 2007.233); B, F, P. segnis (134.5 × 62.6 mm) (ZRC 2007.226); C, G, P. reticulatus (138.5 × 60.7.0 mm) (ZRC 2007.222); D, H, P. armatus (133.0 × 66.0 mm) (ZRC 2007.229).

Fig.24.Frontal view showing differences in branchial swelling.A, Portunus pelagicus (152.9 × 68.0 mm) (ZRC 2007.233); B, P.segnis (134.5 × 62.6 mm) (ZRC 2007.226); C, P. reticulatus (141.7 × 63.0 mm) (ZRC 2007.222); D, P. armatus (150.8 × 73.6 mm) (ZRC 2007.232).

Fig. 1. Schematic drawings of a generalized Portunus pelagicus illustrating morphological terms and measurements used in the study. A, dorsal surface and appendages; B, cheliped; C, pereiopods; D, abdomen.

Fig. 2. Scatter plot of canonical scores from forward stepwise discriminant function analysis. Group 1, Portunus armatus; 2, P. reticulatus; 3, P. segnis; 4, P. pelagicus.

Fig. 3. Minimum Evolution bootstrap tree incorporating all unique COI haplotypes. Haplotypes of specimens obtained from Portunus pelagicus, P. segnis, P. reticulatus and P. armatus with P. trituberculatus, P. sanguinolentus and Charydis lucifera as outgroups. ‘*’ Indicates the dominant haplotype found in P. pelagicus shared with eight P. reticulatus individuals. ‘**’ Denotes two individuals collected from Japan that may constitute a possible cryptic species.

Fig. 4. Frequency histogram of intra and inter-specific divergence for COI locus for the four species excluding outlier haplotypes for clarity.A, Divergence between Portunus armatus and P.reticulatus; B, divergence between P. pelagicus and P. segnis; C, divergence between P. armatus/P. reticulatus and P. segnis/P. pelagicus.

Fig. 5. Minimum parsimony spanning network constructed with TCS of Portunus pelagicus complex using a 573-basepair fragment from the COI gene. Each line represents one substitution; small unshaded circles indicate additional substitutions separating two haplotypes. The size of the circle is representative for the frequency of the haplotypes. Filled patterns correspond to geographic affinity of haplotypes. Network for: A, P. pelagicus; B, P. segnis; C, P. reticulatus; D, P. armatus. For key to localities, see Table 6.

Fig. 17. Portunus armatus (A. Milne-Edwards, 1861). A, Lectotype male (36.0 × 15.0 mm) (NHM 1858.172.115) (photograph: P. Crabb, NHM photo unit); B, original figure in A. Milne-Edwards (1861).

Fig. 18. Lateral spine length variation in juvenile Portunus armatus (A. Milne-Edwards, 1861). A, B, Botany Bay, New South Wales; C–F, Shark Bay, Western Australia. A, male (27.14 × 12.4 mm) (ZRC 2007.236); B, male (28.5 × 13.9mm) (ZRC 2007.236); C, male (30.7 × 13.9 mm) (WAM C20682); D, male (29.5 × 12.3 mm) (WAM C39181); E, male (34.0 × 14.5 mm) (WAM C39181) F, male (26.8 × 10.9 mm) (WAM C39179).