SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a74f250a0c403c08f15c22ca7a1392c1ae4bcd79b0c67ab9c2b81e83ed274a8' 
  AND token = 'D8PjUjVZqidWlsCtAIsiFdGXpmVvPr7u6TWGgfV2JpY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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