SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a593145d9a380e1bc8acd0e64019f3fa2ccb5fbbd8253b19a8af242996d7669' 
  AND token = 'z0DPq5ele5TL/OL4JojcpD1Ux+tS/Vd1IyEfW3PaIaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00133

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