SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c2deb20a2a75c884320f7e332f489b7d1b64e8e6f6ae4d0b8a602196c31b9e3' 
  AND token = '3zJjpKlE9357xV+zCNef+sgiLpru5w0VFOQ/Hg6PjY8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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