SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '846a1e8bf20e86143b58d2ec4cfbe080c63935aa15c7d64ef5be57201238a038' 
  AND token = 'rqbCL/ol1bhJEPeu7HjAJBv4DhvS4UaBVVM/YU41qv0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

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