SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '005f98a3e1de3b444879227a8c5819b87a60100dcae68b30c8976719f274187b' 
  AND token = 'lgWd8VoFCG4/gZcdLv2j0A7W+hCFvPHPktPnE6GmKhE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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