Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7858e8c806a3ed4fb56dc9891de461ea694e3b78f193e99feb07ffa446f2833a' 
  AND token = 'Mb5d6BYkQy5J/7Ylg0Fre8mlY0cZhm7n4+9Dn6I1wNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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