SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95af641bd483cb81264d9fbf627f9a52c2ce530915fd7f4d28039d50f758bbd9' 
  AND token = 'mCgwD3ep7z44WgsL3xzW0NUllueqllwsvFrgdXTjqzg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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