SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a81f02356d3aa32132f77e37157e92007e8a7c6e3feca7fd4d91af9b1b53c1e8' 
  AND token = '/KN+Ozyi6V+DtXwx09uiLVo4EPOWBed740/flRgjMAo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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