BUENOS AIRES, May 11 (Reuters) - Argentina's stock, currency and bond market trends on Monday.
* The MerVal stocks index .MERV rose for an eighth straight session, boosted by purchases of banking and service sector shares, traders said.
* The index gained 0.8 percent to end at 1,512.11 points, accumulating a nearly 22 percent gain since April 29.
* Grupo Financiero Galicia (GFG.BA), the financial group that holds Argentina's biggest bank, jumped 8.5 percent to 1.03 pesos a share as investors bet on positive first-quarter earnings.
* On the broad market volume was modest at $13.4 million. Of active issues 41 advanced, 22 declined and 15 were unchanged.
* Prices for government bonds traded over-the-counter in Buenos Aires shed 1.9 percent as investors continued taking profits after recent gains.
* Argentine bond prices are trading at levels not seen since October when the global financial crisis and President Cristina Fernandez's surprise nationalization of private pension funds sent the country's sovereign debt sinking.
* The peso-denominated 2038 Par bond ARPARP=RASL fell 3.1 percent to an ask price of 18.90.
* In formal exchange between banks, where the central bank intervenes nearly every day, the Argentine peso closed 0.07 percent firmer at 3.7175/3.72 per dollar ARS=RASL.
* In informal trade between foreign exchange houses, as measured by Reuters, the peso slipped by the same percentage to 3.7450/3.75 ARSB=. (Reporting by Jorge Otaola and Walter Bianchi; Writing by Hilary Burke)