SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '805f027dd4d639302d0e9090b08f964eb19bfb496d8dba6eceb94dad640f4f59' 
  AND token = 'T39FeWf9z9GAZ6O3mf29XVdBJKnsaNQZtyUrsWEJQcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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