SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d7cf0c1f14aeee5a88e4d83fcc6006ecdb633d37690ec52bb788e5c32b4bf1e' 
  AND token = 'rQZcoBA4khbwM6SZt1/lpx0liP7c+OR06dOHnfQpPE0=' 
  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