SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd95caa011f0c8d1f93dde4e1cccc0eeefa9febe387d7be8c2b9663aaf6a94cc2' 
  AND token = 'OFIwmwJzp4AAyRVN8/u+Rf50CV1OUwqBK/gXvVQm6Lw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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