SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e664ca163a341e935ce19f109f9b6ee46d0920141549cd09e8d63d349c2bba29' 
  AND token = 'FF7Btb/jJwdEejPj/crD0cHrvoHRXma1BGUuRIQCEgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

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