SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6294148736d5433787c71804db8c89ad6d5f4711ba7321babec45e26a078c841' 
  AND token = 'VIK/BOyWMrQCZu2ZrFvGUHDc+y+mtZMzTSRVX//RB28=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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