SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cad5d65fa6c16679b6b620b19f331aaa788b1d389522de00e1e4484ce57b721' 
  AND token = 'xYfZEs4HfzABxxpJ5ao7VyWDAkYA7ZlN1ENHxXAotTA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

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