SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '837980eacd69a1a437913c7fab38adfc91d014db00fa1b706ed12a3656a35940' 
  AND token = 'Tiy2mClc3T9PB++j8BVAMRjFD06oaEKkjL3Kubg7Lls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

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