SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b11c1eea780d727be45b1a4d4a41a43f3ef425378380bb079dc8cdafe2ba5171' 
  AND token = 'ILLUgXM+rGj4jqXmKdAzL3vHZl+nhF2s7p2Qm0bzsKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

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