SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '806eaa46b95fb2c3670513857db165b6534577f085a3551f58419e024cff0947' 
  AND token = 'WLKdxBlcTVMX5f72n6kwmn2JJK7HgZsJf1m8lt9MFsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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