SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '140976b943a1a19752dc11e75e8aefbc77e99230ec7c32778fa6ee51290cdf4f' 
  AND token = 'NTCFkc54AqJrNpsSDg5TJ/adY2jq9ASuD9coTe2LnhM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

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