SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91ce59ae4eef8b8a7fcdddea4709666e1a6f128f7e1dac37bc302d26ad3df67b' 
  AND token = 'nOmYqSW6TS3OdcpIyNovPzrC0XyjXfrfRT5u8pPg7OE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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