SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fedf4a542c9b410a8990997418c663b7f92875a7db23c1c34d31b38d934ab927' 
  AND token = 'hQfPFHamTS/iqpvSr5xPqEKCwFuOOaGewPK4le2kCP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

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