SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e8b21e80d6825ec706a4e1c2ddd47a01a995ed2b864295650d2b4875f9adb49f' 
  AND token = 'UJN3rWIL/MMCYEmi9sLo9fHpSubVv5ZHRe6q8ouXnZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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