SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f768060e6d175171ee91b2ba12283ee9ea1451d8d7028820181b21643f4fe51' 
  AND token = 'SvegpNmilvQU/DbNNf+yJeHGawEfqtuOkN/EPLHiHKE=' 
  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