"Paralomis formosus, n. sp. (Pl. V. fig. 2).
Characters.—The carapace is broadly ovate, with the length and breadth subequal, everywhere covered with pearly granulations, which are mostly arranged in groups; the regions are fairly well marked. The rostrum is composed of three subequal spines, the two upper considerably elevated and widely diverging; the lower almost horizontal. The gastric area is convex, and bears towards its centre a conical and acute spine of large size, with, on either side and slightly posterior, a small tubercle, and two short pyramidal processes at the posterior part of the area. The surface of the gastric spine, as in the case of all the other spines found on this species, is granulated. The cardiac area is convex and moderately circumscribed, capped by four tubercular spines arranged as if at the four angles of a square; the groove which separates this region from the gastric area is smooth and devoid of granulations. The branchial area possesses a prominent and acute spine opposite the centre of the cardiac area, and towards the posterior border of the carapace one or two tubercles. The cervical groove is represented on the surface of the carapace by an irregular, sparingly granulated depression, at the anterior end of which there is a smooth oval elevation. The external orbital spine arises internally to but in line with the antero-lateral spine, the lateral border is armed with five or six spines, two of which are situated in front of the cervical groove, while the two immediately behind this are largest in size; the second spine is curved forwards and inwards. The posterior border possesses one or two tubercular spinules on each side and from four to six small subcentral tubercles.
The ocular peduncles are granulated above, and, as in the last species, terminate in a small spine; the corneae are oblique and deeply pigmented. The second joint of the antennular peduncle extends to a point opposite the end of the antennar peduncle; the first joint of the latter possesses a prominent and acute external spine, the second bears one of much larger size with a secondary projection at its base; the squame is quadrispinose, two of the spines being of small size. The merus of the external maxillipedes is slightly granulated externally. The pterygostomial region bears a somewhat blunt spine anteriorly.
The chelipedes and ambulatory limbs are long, and as in the case of the carapace covered with fine granulations, which are more numerously arranged on the upper surface. The chelipedes are subequal in length, the right being stouter; the meral joint is furnished with two prominent spines on its inner and distal border, and several are also present on the carpus, the two posterior of these being of large size and curved; the propodus bears a double row of large tubercles on its outer surface, and a series of tubercular spines on the upper border; the fingers are each provided with three rounded teeth and numerous tufts of hairs. The meral, carpal, and propodal joints of the ambulatory limbs are bordered anteriorly by stout spiniform processes, of which one at the distal end of the merus and carpus respectively is most prominent; the posterior border of the merus and propodus bears a somewhat smaller series; the propodi are moderately curved, tipped with dark corneous spines, and fringed inferiorly by a row of horny spines.
The abdominal plates are distinctly granulated; the second segment bears two blunt spines on a mesial elevation, and two subcentral tubercles on the posterior border; the penultimate segment bears a terminal projection on each side, and the telson is bituberculate.
The above description is taken from a male. In the female, which is of slightly larger size, the spines on the carapace are comparatively more strongly developed.
The following are the chief measurements in both sexes: --
Male
Female
Breadth of carapace
14.5mm
15.8mm
Length of carapace
14.5mm
16mm
Length of rostrum
4mm
4.5mm
Length of right chelipede
22mm
24mm
Length of first ambulatory limb
28mm
31.5mm
Length of last leg
8mm
9mm
Length of abdomen
10mm
11.5mm
Habitat. – Station 320, off Rio Plata; depth, 600 fathoms; bottom, green sand. Two adult specimens (male and female), and two immature."
(Henderson, 1885)
El centollón (Paralomis formosa) es una especie de crustáceo decápodo que integra el género de cangrejos litódidos Paralomis. Habita el lecho marino de las frías aguas del sudoeste del océano Atlántico y parte septentrional del Antártico.[1]
Paralomis formosa fue descrita originalmente en el año 1888 por el científico John Robert Henderson.[2] El ejemplar holotipo fue colectado en las aguas marinas frente al Río de la Plata, a 600 brazas de profundidad, sobre fondo de arena verdosa. Fueron capturados 2 adultos (macho y hembra) y 2 inmaduros.
Se distribuye en aguas de la plataforma continental del mar Argentino (tanto en el Uruguay como en la Argentina);[3] además en las islas Aurora, Georgias del Sur,[4] y Orcadas del Sur.[5] Habita en aguas oceánicas profundas y frías, generalmente en áreas próximas a la zona de ruptura de la plataforma.
Datos: Q14017279
El centollón (Paralomis formosa) es una especie de crustáceo decápodo que integra el género de cangrejos litódidos Paralomis. Habita el lecho marino de las frías aguas del sudoeste del océano Atlántico y parte septentrional del Antártico.
Paralomis formosa is een tienpotigensoort uit de familie van de Lithodidae.[1] De wetenschappelijke naam van de soort is voor het eerst geldig gepubliceerd in 1888 door Henderson.
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