SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '50778c49cd7c642afef1b6a9f5598a6e7207d4c16d26b5bd094832f891a9c4c8' 
  AND token = 'sTi6Dn0IRPxoRxtCm+kjAEwcaTO+YrnPrxudaQXU4b4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

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