SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d1f0f20581b8aa592ecdc38c974cec8bdc5cb96f97595b82852ebd8e664f482' 
  AND token = 'xESQdkupg8zS+Wz9Hs8yb9ZtkG2M6q2DgYahKNpxx+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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