SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ce44696a22265f40388961c5ff57fb7652dd18dcd5f100e2988d3a4e07adf384' 
  AND token = 'WGvTYq9Dy4kJdiJPT3cCbVKJ/VLcZQa0nmtvKv+B60s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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