SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c945a721318ee49145a7f24ec601dba1367f3590c2fec2c43c5d21e1c4ec70fe' 
  AND token = '3rUwreC0cTM+h7/fSunPNg8pkMz83cjsboEoTTR3eek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

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