SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6a816d37264a835c706214b75dccedb53ec07d9726490e41c99192bee18c5414' 
  AND token = 'cxLR4C5D/bHVrKM0RtChOX6d9x5oyFt68mFX7HR0Hrw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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