SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '18c27ea1ab961fe4d604a5799f2148800eba1b92b56d76d8889f58092ab28d15' 
  AND token = 'GPqaia0HDDry/aCf+Nv0AS4O4B8Kc4n7LKIpknEEBdU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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