SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3996056f369d1a493b64334438fd65499197e825cd8245e22afc52888957c52e' 
  AND token = 'o1ECOcR7JsjPKVCYK56LkSPW+XHOTAdj5u2+3m0hQrk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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