SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2aaee0668fd18ddde7af20a00f19e77a1debe217614eb7461082434c8deb789e' 
  AND token = 'Nk6/uF+SRbJtiKfJVsypnTr3sd54cswnd3qAUnpm3f8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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