SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c166fa53197a0b33dd1839ea2fc200eb69a9034cf159e4ae6198e995a392a7d9' 
  AND token = 'b/nbc07qtItPcjezvlmZeR2RPBrcPzqisjn/O4MmyzA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

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