SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd415ada9401ed777d70fcf988db2b6633fa22224320a8e669c0869b361133274' 
  AND token = 'p406xNZcOKLNi/WRM/4LKYq94bf2tf7/9hb0q6yrEvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}