SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8be02b150398f403b717b0004556876892b4b496f3d1c4dea359bd5673b8397a' 
  AND token = 'Z+Wk1RmutiVcDKstBYEYG9jvutX7lIOns1nayeYfpqc=' 
  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