SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3ef3441abdfb075f491d2a36d7a44bfbcd5b6031a78380726435d86c9e32fb3c' 
  AND token = 'Dj4LJCcxmWdRmdfKPqzmhlCV3nSK1Kf0G9BF6eubwoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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