SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '631ab1294330b2747077309cdd715b8cf414ab96cc46d71dfe9f372279f8cdb7' 
  AND token = 'myMeV5xq4YRUkUj5hV9nGY2Y3VRLz5D2RBFVYj/t+Q8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

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