SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'bae05bf20afa24ee5f47099820d97eb2190bcdc3a65bddc20560cb1375623974' 
  AND token = '6n1td/AvsxkN35AOh62WGL+L6xZU6U4At1a1CgeFCPM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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