SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd66d2df924df815179f937b8e47341e18f2ece8d5716bb7196c26c8f9f352b62' 
  AND token = 'u0sujgHqQGG72nhqud0floN/YhjZalD9/ivtYmiTzK8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

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