SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a720db811facee58e90b241499c4e65a5363c5cda749a9e3d674e9b608e5566' 
  AND token = 'htPY0PdZmedPiPge2foGjDUXIKHyUybiJuNNQoYD15s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables