SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd8e4a4e78c4e420c162e7fd9ce68e6608414d0bdf78ae971e93bd9380630529' 
  AND token = 'C81C8n2PvCv1QA07WHSfBe3LOqP9ZIPeOUW2QHl3uzY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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