ZYGOGKRAMMA. 209 



ZYGOGRAMMA. 



Zygogramma, Chevrolat in dOrbigny's Diet. Hist. Nat. iii. 1843, p. 656. 



This genus can only be considered a modified form of Calligrapha, which it 

 resembles exactly in its principal structural characters, as well as in the peculiar 

 arrangement of the elytral markings and the sculpture connected therewith. We meet, 

 however, here with forms which are strangers in the latter genus in regard to the 

 elytral designs, some species of Zygogramma exhibiting alternate stripes of dark and 

 light colour of regular parallel shape, which are not found amongst those of the preceding 

 genus, where a system of spots prevails. Where this latter occurs in the present 

 genus, the claws united at the base to a greater or less degree will at once decide 

 the proper place for the species, those belonging to Calligrapha having in all instances 

 the claws widely and distinctly separated. Zygogramma extends throughout the entire 

 American continent, Central America furnishing twenty-nine species. I cannot agree 

 with Chapuis as to the position he has assigned to his Zygogramma zetterstedti, which 

 has been, I think, rightly placed by Stal in the genus Leptinotarsa. 



l. Zygogramma nicaraguensis. (Tab. XI. fig. 21.) 



Greenish aeneous below ; antennae and legs obscure rufous ; elytra obscure testaceous, the suture split into two 

 branches anteriorly, a stripe at the shoulder connected with the second branch, a spot near the scutellum, 

 three others at the lateral margin, one below the other, seven spots below the middle, and a V-shaped 

 mark near the apex obscure greenish aeneous ; claws united at the base. 



Length 4 J lines. 



Head finely punctured, flat, with a central finely impressed line ; labrum and antennae rufous, the last five 

 joints of the latter widened, nearly as broad as long, opaque, the basal joints shining. Thorax transverse, 

 of nearly equal width, the sides rather deflexed and slightly rounded ; anterior angles acute, but scarcely 

 produced ; surface with a shallow fovea at each side below the anterior margin, finely and remotely punc- 

 tured on the disk, the sides strongly punctate. Elytra elongate, moderately convex, of an obscure testaceous 

 colour, with the darker marks also obscure, brownish or greenish aeneous ; of these, three are placed at the 

 lateral margin, one before, one at, and the third below the middle, all of them of rather elongate shape ; 

 the stripe at the shoulder is of an elongate shape, extending to about one tbird the length of the elytra, 

 and is divided posteriorly into two parts or branches, the inner one joining the sutural band at the side of 

 its second division or branch ; between this latter and the base a round spot is placed (in the figure this 

 spot ought to have been isolated) ; three other spots of unequal shape are attached to the sutural band 

 below the middle, the last of which forms a U-shaped mark near the apex ; the rest of the disk near the 

 sides is further occupied by two or three hook-like marks of irregular shape, for the most part attached to 

 each other at one point or other. 



Hab. Nicaeagua, Chontales (Janson). 



This species, of which I have two specimens before me, has the usual markings of a 

 species of Calligrapha, from which I must separate it on account of the structure of 

 the claws, which are united at their base ; the ground-colour of the elytra is greatly 

 reduced in extent on account of the size and number of dark spots and stripes ; the three 

 narrow elongate spots at the lateral margin will separate it from somewhat similarly 

 coloured species of Calligrapha, although I do not know of any species with, which to 

 compare it, the nearest approach to it being, perhaps, C. intermedia. 



biol. cente-amek., Coleopt., Vol. VI. Pt. 1, October 1882. 2 e 



