SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ef2f98f8c4760e976cc6ec9fb4112ee9482547b91dbecb186065037362f98fca' 
  AND token = '2pIfxSYJw5DMxTHZsQhkd8E1/8CpE0hI+gbYdRstnqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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