SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbe728444b06688ee73822488a0223eafeda39e4b0961d57c547625e4ddbbc88' 
  AND token = 'QnPtfxDTDVv0xa0Jd2IyvcktTOIN98bo+xvRaloYpww=' 
  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