SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1a909f528f1512c3cb08d3a9911713edac2da0c8803128c3f5f308597a22604d' 
  AND token = '5hqzQQzAeYXry5sKEt58r7dnJ81IWS9WxGme6+VMXBY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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