SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fad69772c8edc19b4867aeabdfaa2c4084591ee116d62096af4546d39dc444fd' 
  AND token = 'dHydw7AKfZJ4jGWsEj5FXoGBBaiE2+KVFnnQX2uI6mI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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