SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '99cd3668240c042c655c468049950c5f35793a247cfa93a04e7d6f93d8198a89' 
  AND token = 'csN4MJ2MSUt4ZhhbcxvFFcAXk4PFy3yuB50JsnYRirg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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