SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2836b1dbe0e0e7749e008abc484d37d48d0c474cc34efdfd3de2bbe50965b7c8' 
  AND token = 'kxjfW8XYsUKJoIqbtjVQ59GddI+JrONhB1DDa6wd3ro=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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