SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b2c13e20ff37aa25a02fde39695cb8e03e5690fa339b1a9c94b6e5c90b673e0a' 
  AND token = 'K/cwjRUgdgYEHG41nSyfd+b9o9icueTdmigjJo3sypo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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