SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdef758b285c9eb75b423bfb9afd3885896c651e2356c0ea8f495106a8775725' 
  AND token = 'w65Tz5qx2qg5AgD+dQmOeOKZvT6OdJvE4gOVm1jMIjw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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