SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b0099cca650cdbf9e6f3ed104b9ebbbec4620a78e134d2fce6756b057f7741a' 
  AND token = 'Uwah1nShvw053G0MIOgXXW2vg8oiksIBKpHleAnvVpQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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