The present contribution reports a positive allometry of cheliped
for both juvenile and adult individuals in pre-puberty molt, reaching the highest level in the adult phase.
Induction of outgrowth at wounds on the cheliped
of PrCambrus clarkia (Decapoda, Cambaridae).
After close examination, the approximate number of eggs of each group was recorded to see if there was any relationship between size of the male's large cheliped
and the number of eggs produced during reproduction.
Geometric morphometric techniques were used to evaluate morphological variation in shape and size of the carapace and right cheliped
paulensis, the present study aimed to: 1) determine the sizes in which males and females reach their morphological sexual maturity, 2) characterize the relative growth of the species based on allometric changes of carapace length, width, and height of the cheliped
propodus, gonopod length, and abdomen width in relation to the carapace width, and 3) verify the occurrence of heterochely in both sexes.
In this case, early maturity in brachyurans can be detected by changes in the growth proportions (relative or allometric) of structures associated with secondary sexual characteristics such as the cheliped
in males and the abdomen width in females (Hartnoll, 1974; Hartnoll, 1982; Pinheiro & Fransozo, 1998).
The following morphological characteristics were measured: the carapace width (CW), the height and length of the major cheliped
propodus (LPH and LPL), the width of the female abdomen at the base of the 4th somite (AW) and the length of the male gonopod (GL).
basis with small inner dorsodistal process; carpus about twice as long as wide.
The morphometric measurement of carapace, abdomen, cheliped
and male gonopod were related to carapace width as an independent variable.
1 A); right cheliped
larger than left; merus with 3 crests as follows: upper crest with rows of tubercles, internal lower crest with row of teeth, diminishing in size proximally, and external lower crest with row of low tubercles; carpus with blunt distal spine; palms of both chelipeds
smooth, swollen; fingers of chelae with rows of tubercles, slightly gaping when closed, tips crossing (Fig.
Males become gonadally mature (spermatophores and seminal fluid present in the medial region of the vas deferentia) at a very similar carapace width (CW) to that at which they achieve morphometric maturity, as reflected by a change in the relative size of the largest cheliped
Intruders with a naturally missing, presumably autotomized, major cheliped
were as likely as intact intruders to escalate a contest but were less successful in gaining the female compared with intact males (Yasuda et al.
Hemolymph (1 ml) was collected from the arthrodial membrane between the coxa and the base of the cheliped
using a 1-ml syringe with a 23-gauge needle.
Also the carapace and outer cheliped
surface are largely punctuated.
The severity of black spot disease was classified on a scale from 0 to 4: (0) no discoloration present; (1) one to five distinct spot, generally only on chelipeds
; (2) the spot number varied between 6 and 10; (3) many distinct spots (more than 11), usually covering surfaces of chelipeds
, abdomen, and carapace; (4) much discoloration; much of the surface of cheliped
, abdomen, or carapace are affected, and solid black patches can be seen.