Arenaeus cribrarius ( Lamarck, 1818 )

Zupolini, Lucas L., Magalhães, Tatiana, Pileggi, Leonardo G. & Mantelatto, Fernando L., 2017, Taxonomic revision of the speckled crabs, genus Arenaeus Dana, 1851 (Brachyura: Portunidae) based on morphological and molecular data, Zootaxa 4273 (3), pp. 362-380 : 366-368

Arenaeus cribrarius ( Lamarck, 1818)

( Figs. 1 , 2 )

Portunus cribrarius Lamarck, 1818: 259 (type locality: Brazil, type in Muséum national d’Histoire naturelle, Paris, not examined).

Lupa maculata Say, 1818: 445 .

Lupa cribraria H. Milne Edwards, 1834: 452 , pl. 17, figs. 1–4.

Arenaeus cribrarius — Dana 1852: 290, pl. 18, figs. 2A–B.— Rathbun 1901: 50; 1930: 134, pl. 58, figs. 2–3, pls. 59–60.— Hay & Shore 1918: 434, pl. 34, fig. 3.— Williams 1965: 173, fig. 153; 1974: 30, fig. 86; 1984: 362 fig. 292.— Coelho & Ramos 1972: 188.— Taissoun 1973: 52, photo 9, figs. 8A–9A.— Felder 1973: 55, pl. 8, fig.4.— Powers 1977: 74.— Rodríguez 1982: 150, fig. 5 p. 148.— Melo 1996: 311.

Neptunus cribrarius A. Milne-Edwards, 1861: 211 .

? Arenaeus websteri Jones, 1968: 156 , 155 (photograph).

Type locality: Brazil.

Known range: from Massachusetts, USA to Mar del Plata, Argentina. In Brazil, from the state of Ceará to Rio Grande do Sul ( Williams 1984, Melo 1996, Scelzo 2001).

Material examined. MEXICO (Atlantic coast): 1 male (CL 30.41 mm) UNAM 9639 : Punta Estrella , Puerto Morelos, Quintana Roo, 19.ii.1972, (J.C. Nates, A. Cantú, J.L. Villalobos, D. Valle & P. Schmidstorf coll.) ; 1 male (CL 23.50 mm) UNAM 3579 : El Morro de la Mancha , Veracruz, 20.viii.1984, (D. Baños coll.) . COSTA RICA (Atlantic coast): 1 male (CL 47.50 mm) and 1 female (CL 25.64 mm) UCR 2017-02 : Tortuguero Beach , Limon, 9.i.1995, (J. Cortés coll.) ; 1 male (CL 15.45 mm) and 1 female (CL 27.20 mm) UCR 2470-10 : N.O. Pájaros Island, Moín , Limón, 25.vii.2006, (K. Rodrigues & M. Mug coll.) ; 2 females (CL 33.37 mm and 28.70 mm), CCDB 2930 : Playa Negra, close to Estero Negro, Carretera , Cahuita , 22.v.2010, (F.L. Mantelatto et al. coll.). VENEZUELA: 1 female (CL 42.41 mm) CCDB 3635 : La Restinga (El Saco), 25.viii.2011, (J. Bolaños coll.) . BRAZIL: 1 male (CL 11.34 mm), DOUFPE 6880: Meireles, Fortaleza , Ceará, 14.vii.1977 (coll. not given) ; 2 females (CL 24.10 mm and 18.86 mm), CCDB 3391 : Pirangi Beach, Parnamirim , Rio Grande do Norte, 8.vi.2011, (R. Robles coll.) ; 1 male (CL 10.46 mm), DOUFPE 6873: Tambaú , Paraíba, 01.vii.1964, (coll. not given) ; 2 males (CL 35.63 mm and 45.31 mm) DOUFPE 6876: Tambaú , Paraíba, 25.ix.1972, (coll. not given) ; 1 male (CL 10.51 mm), DOUFPE 6893: Candeias , Pernambuco, 30.vii.1988, (coll. not given) ; 1 male (CL 29.42 mm), DOUFPE 6871: Jaraguá Beach, Maceió , Alagoas, 28.vi.1981, (coll. not given) ; 1 male (CL 32.13 mm), CCDB 5936 : Praia de Maragogi, Maragogi , Alagoas, 05.x.2013, (E.A. Souza-Carvalho & F.L. Carvalho coll.) ; 1 male (CL 17.24 mm), DOUFPE 6861: Santa Cruz Cabrália , Bahia, 10.ii.1999, (coll. not given) ; 2 males (CL 48.59 mm and 45.71 mm), CCDB 3255 : Macaé , Rio de Janeiro, 10.vii.2011, (R.C. Costa coll.) ; 1 male (CL 52.39 mm), CCDB 2725 : Ubatuba Bay, Ubatuba , São Paulo, 30.xi.2005, (F.L. Mantelatto coll.) ; 1 male (CL 36.72 mm), CCDB 1536 : Ubatuba , São Paulo, 17.viii.2011, (D. Rosa coll.) ; 2 males (CL 50.75 mm and 47.13 mm), CCDB 754 : Caraguatatuba , São Paulo, vii.2001, (F.L. Mantelatto coll.) ; 1 male (CL 29.88 mm) CCDB 291 : Guaiuba Beach, Guarujá , São Paulo, 22.x.2011, (F. Carvalho et al. coll.) ; 1 male (CL 29.30 mm), CCDB 3700 : Peruíbe , São Paulo, 14.xii.2011, (L. Zupolini & R. Amaral coll.) ; 1 male (CL 24.31 mm), CCDB 3208 : Boqueirão Norte Beach , Ilha Comprida, São Paulo, 17.iv.2011, (F.L. Mantelatto et al. coll.) ; 1 male (CL 14.44 mm), CCDB 3182 : Boqueirão Sul Beach , Ilha Comprida, São Paulo, 17.iv.2011, (R.C. Costa et al. coll.) ; 2 males (CL 15.06 mm and 30.35 mm) and 1 female (CL 34.68 mm), CCDB 3241 : Cananéia , São Paulo, 18.iv.2011, (T.M. Dawanso et al. coll.) ; 1 female (CL 30.58 mm) and 1 male (CL 51.61 mm), CCDB 3516 : close to São Francisco do Sul , Santa Catarina, 10.viii.2010, (S. Moura coll.) ; 3 females (CL 22.19 mm, 35.12 mm and 27.69 mm) and 3 males (18.57 mm, 23.77 mm and 27.44 mm), CCDB 1461 : São Francisco do Sul , Santa Catarina, 28.v.2011, (A.L. Castilho coll.) ; 1 female (CL 35.02 mm), CCDB 1457 : São Francisco do Sul , Santa Catarina, 25.v.2011, (A.L. Castilho coll.) ; 1 female (CL 41.52 mm), CCDB 990 : Santinho Beach, Florianópolis , Santa Catarina, 28.i.2004, (F.L. Mantelatto coll.) .

Diagnosis. Rostrum with 4 teeth, the 2 median teeth more widely separated than outer ones; spine at the epistome region present, not much advanced in relation to the front; 2 sharp spines in carpus.

Redescription. Yellowish orange, brownish yellow, greyish or olive brown, abundantly covered over dorsal surface with small, rounded white spots. Front (frontal region) having a spine in the epistome region, between antennules, not much advanced in relation to front. Rostrum armed with 4 small teeth, the 2 median more prominent, more advanced, more widely separated from each other than outer ones. Carpus of chelipeds with 2 short but developed, sharp spines, one on the outer face, second on inner face of carpus; outer spine continued proximally as obsolete carina. Male gonopods (first pair of modified pleopod) generally overreaching the telson tip and crossed over by its final portions; tip moderately attenuated.

Remarks. We attempted several times to reach the holotype from Muséum national d’Histoire naturelle in order to confirm the condition of the type. However, we have not received response whatsoever at the time of writing this manuscript. Based on our set of specimens analyzed, various subtle differences are found in juveniles in contrast to adult and larger specimens. Inter-regional sulci on the dorsal surface of the carapace are more marked in juveniles, resembling the equivalent condition in A. mexicanus . Consequently, the inner branchial lobule appears more prominent in younger individuals. The first four anterolateral teeth, except the outer orbital one, are similar in size and smaller than the consecutive teeth. The lateral horn is apparently sharper and proportionally longer. The spine in the epistome is less prominent. Outer teeth in the rostrum are less developed and prominent, while the inner ones are similar to the adults’; the outer incision in the superior orbit border is nearly unapparent. Finally, the transverse sinus in the cheliped distal portion of the merus is not as deep and marked. Also in juveniles, the caudal extremity of the telson is less attenuated, nearly triangular in shape, similar to the condition in females. Furthermore, some other discrepancies are observed exclusively in smaller specimens rather than in every juvenile. The merus of the swimming legs, for instance, is slightly shorter in proportion compared to larger juveniles. In one specimen, the ischium of the first pair of ambulatory legs presented 2 instead of 1 tubercular prominence at its distal end.

Some characteristics stated in previous descriptions may also be incongruent or inconsistent. The diagnostic “one spine at the distal end of manus” in Rathbun (1930: 135) is not informative in distinguishing both species. Furthermore, the description of the male gonopods in Rodríguez (1982) does not entirely suit the observations made in this study. The ornamentation pattern suggested by the author does not apply to the whole length of the structure as the basal portion is covered with setae practically in its entirety.

Figures

FIGURE 1. Arenaeus cribrarius (CCDB 754) and diagnostic features. A, dorsal view; B, merus-carpus joint view, with inner and outer spines (arrows) at the carpus; C, frontal view and the presence of a spine in the epistome region (arrow), between the antennules.

FIGURE 2. First left gonopod of Arenaeus cribarius (CCDB 754). A, ventral view; B, tip morphology, ventral view; C, tip morphology, dorsal view; D, subterminal armature, lateral view; E, basal armature, dorsolateral view. Distal margin bent during the preparation (B and C).