SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2230797d6055035f61b499fde5540191a7cfaa2aea82b81c70c334e4acf2323' 
  AND token = '1/68LjBs2xCnYNY5YlJCIFpx89MzGp2AWoaz4HUOR0Y=' 
  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