SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4694981a8f28723448783a412890a410db66795d258f22430e300c9f6d1d3cac' 
  AND token = 'G3IcperVeM+s8agjPjpn3pCE7jID+gz/rNCIFhrmPHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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