SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b40964386162b85e39556759edc6b06ed2317ad1045db57285df933fe072cb86' 
  AND token = 'lUupvVrzaDxipMmamo5V8H/b8WjvclayGy5tXdcgBdU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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