SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2dd165ebd233e6ced8cbfdd82c54fdc4980e2e7eedbdaebdd8591a05477359d3' 
  AND token = 'cY9mt+Bz8F3n9mnVeOYWWUr2wZyaaT5Px62RkxlmWn0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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