SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43f124d3f9125787b871fe81f6394c5b9d5ee8b1cf317362fad0c6e0523eb9c1' 
  AND token = 'tdcZQVN4Yqd6V1Ic3gVwXvhXgQ6BhaEWppjcHV0NBvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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