BUENOS AIRES, April 13 (Reuters) - Argentina's stock, currency and bond market trends on Monday.
* The MerVal stocks index .MERV surged 5.28 percent to 1,224.60 points, buoyed by Wall Street's gains late last week, when the Argentine market was closed for the Easter holidays.
* Tenaris TENA.BA, which makes steel pipes for the energy industry and is weighted as almost half of the MerVal, shot 7.5 percent higher to 44.20 pesos per share.
* Shares in banking group Grupo Financiero Galicia GFG.BA rose 3.7 percent to 0.756 peso, gaining as bond prices improved, traders said.
* On the broad market, stock volume was relatively brisk at $18 million. Of active issues 43 advanced, 14 declined and nine were unchanged.
* Prices for government bonds traded over the counter in Buenos Aires gained an average 2.2 percent, rising some 4.2 percent in the last four sessions.
* Peso-denominated Discount bonds ARDISCP=RASL rose 3.7 percent, according to the ask price.
* Argentina's government said on Monday it sold two issues of Treasury bills worth 1.5 billion pesos ($406 million) to the country's pensions agency, as part of its drive to raise funds without tapping capital markets.
* In formal exchange between banks, the peso weakened for a second straight session, slipping 0.14 percent to 3.68/3.6825 per dollar ARS=RASL. The central bank intervenes nearly every day in this market to avert abrupt movements.
* In informal trade between foreign exchange houses as measured by Reuters, the peso firmed 0.68 percent to 3.69/3.6950 ARSB=. (Reporting by Walter Bianchi; Writing by Hilary Burke; Editing by Leslie Adler)