SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b995393af83be99e07110d36dd9a9442b233babf8f9100fe89346913f9688ed3' 
  AND token = 'CD47TFezhEdciNE3C7n8O+QiuSMlA3AB67PMy9kQTOI=' 
  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