SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99e1471642bc6d6285adf2919428e4b6c2f5b63eda29c5512055127f382a7b05' 
  AND token = '7eJZfjAfXLVUB+qlQVDnc7rn+ymj9ZCIyqbIg6w0294=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

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