SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47688d4bdb717f4d8a5bf905043f580abef2cc40a277979ee98073578702bc7a' 
  AND token = 'vf1msJXSlcre6oD3m7FbE3CymVhDOS8UYspeA+pdiGQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

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