SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '050488dd947c5a48e3fa5017c3935d98c642b23c45a7bffe9617ce92dc74eb23' 
  AND token = 'cdoCbEsV//EBLXqg3O8/RQruo4C5nNXna4vf4kqZCR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}