SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '115b182bee868d5a8429fc9a81a8df7f798ba41d4369fd97013e2b52fab7a546' 
  AND token = '8ksTx6LzYmTRG5/YJzbNBnPIRLz9FFLCJCF2UsOoqho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

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