SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff197f63cd8ac865bdda7dd43b1c9bf4476e1f52b5611f70107552102a065a98' 
  AND token = 'vvinaRa7jD3LwwWxGvd57Dd4SVFWAi+YBu8a21AS6a0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}