SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32785618075178be86beab82cefbf41714c3c0a3b263c1dde61229e2df98828e' 
  AND token = 'RhuAGbx5j+vToJ85FV09WCG1uiVGGSrTKYrWBxoKgZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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