SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b6d7c302c57d354c34e02d7f9dfd37be563d6628854c2b0da2c0be92245036d' 
  AND token = 'eVP+IWVFtS5m8JWMevEkRm25OiNMusMND3qQ54oMgEc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

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