SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '938c1e830bdb7f59b439f9cd4ce55513cef8b9de0805772161fa8541fd70387c' 
  AND token = 'X+ehTvwhqnwGiONkn4jPbmnNp3fXkGnhcpZ1GTym/5E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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