SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89cba75d1c78eaf3c37f32d103ded62f700c04adbec11300f49a1aacf1ea38cf' 
  AND token = 'ptpvgc2J4TdaT/aA0DARnenjYM3XmBiBwkUMjLIpGXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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