SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87fd430cb1c23a52a774dc2b089872172a6766f8873ce295b5fdce12fb96a7af' 
  AND token = 'EMrZWHOTK0XCBz12DkA96qOhDZ2UhbkImJVJoBDKW9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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