SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87157c10a091bd94e02a4a11b81150e41ffcee809176136ef308999e2fc05979' 
  AND token = 'syzU6AUDvQuI5phAtFrjRo+I5NwvT9I28tj5mpvhjTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

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