IAM Cycling rider comes off best in a scrappy finish, but elsewhere Alberto Contador's overall ambitions were dealt a knock by a late crash
Alejandro Valverde (Movistar) came over the line in third to collect four bonus seconds as he continues to push for the red leader’s jersey.
The final 600 metres of the parcours was a winding, uphill sprint and a late crash on one of the turns took down a number of riders.
Among those to go down was Alberto Contador (Tinkoff). He was able to ride over the finish line but was clearly scuffed and appeared to indicate an injury to his hand or wrist.
Luis Leon Sanchez (Astana) and Simon Clarke (Cannondale-Drapac), who had been part of a five-man secondary breakaway, looked like they might have held on to contest the stage between the two of them but the front group came past them with under 200 metres to go.
The obligatory early day breakaway contained six riders, who were allowed to carve out an advantage of around 3-20 before the chase began to pay attention.
The riders who went up the road were Victor Campenaerts (LottoNL-Jumbo), Johan Le Bon (FDJ), Sander Armée (Lotto-Soudal), Davide Villella (Cannondale-Drapac), Vegard Stake Laengen (IAM Cycling) and Luis Angel Maté (Cofidis).
After dangling away and working reasonably well together, the break could not hold off the inevitable catch and despite some later efforts, the remainder of the group was passed with 43km to go.
Astana took up the pace making at the front of the peloton, with Movistar following close behind. The whole bunch got strung out following the fast pace set by the Kazakh squad on the lower slopes of the Alto de Padornelo as the team looked to shell any rivals before the long descent and short uphill sprint finish.
With 29km to go to the finish, and around 11km out from the summit of the third category climb, a secondary breakaway went off the front of the peloton.
Clarke and Sanchez, the final two to be caught, were original accompanied by Dario Cataldo (Astana), Gianluca Brambilla (Etixx-Quick Step), and Maté – who’d been in the original break- as they rode away and soon gained an advantage of 30 second, which grew towards a minute.
As the lead group went under the 10km to go banner arguments about who was working kicked off and the peloton bore down behind them. Sanchez and Clarke kept the move going and held a gap of around 10 seconds for several kilometres, even extending it to 18 seconds for a little while.
With three kilometres between the peloton and the finish line, Bora-Argon 18 came to the front and tried to finally close out the gap to the two leaders. Grand Tour record attendee Adam Hansen (Lotto-Soudal) came forward to try and drag the pack over the gap.
Sanchez and Clarke were still away as they went under the flamme rouge but were finally caught with under 200 metres to go as the group came up the sharp closing incline.
Stage eight is the first of three consecutive summit finishes before the first rest day. The 177km from Villalpando to La Camperona goes gradually uphill until the proper climbs kicks up with four kilometres left to race.
Vuelta a España 2016, stage seven Maceda to Puebla de Sanabria (158.5km)
1. Jonas van Genechten (Bel) IAM Cycling 3:55.44
2. Daniele Bennati (Ita) Tinkoff
3. Alejandro Valverde (Spa) Movistar
4. Philippe Gilbert (Bel) BMC
5. Kévin Reza (Fra) FDJ
6. Gedimas Bagdonas (Lit) AG2R
7. Gianni Meersman (Bel) Etixx-QuickStep
8. Kristan Sbaragli (Ita) Dimension Data
9. Romain Hardy (Fra) Confidis
10. Tosh van der Sande (Bel) Lotto-Soudal all st
General classification after stage seven
1. Darwin Atapuma (Col) BMC, 25-41-21
2. Alejandro Valverde (Esp) Movistar, at 8s
3. Chris Froome (GBr) Team Sky, at 42s
4. Nairo Quintana (Col) Movistar, at 48s
5. Esteban Chaves (Col) Orica-BikeExchange, st
6. Leopold Konig (Cze) Team Sky, at 1-09
7. Simon Yates (GBr) Orica – BikeExchange, at 1-32
8. Gianluca Brambilla (Ita) Etixx-Quick Step, at 1-38
9. Daniel Moreno (Spa) Movistar, st
10. David de la Cruz (Spa) Etixx Quick Step, at 2-11