SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b69dcf2d0f3c9bb7cab7a033fba232d14657f1af3007c89d4c98de56071fc4e' 
  AND token = 'eJa0p9YM3u4wBq1B96AhHgNMQheausa4OHlLuSfoulQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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