SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c2c435f2919789a6e9c8d0b1b396b96687808bb09754744684ab0a0342e9187' 
  AND token = 'Qalh3fJ2DcRIUwZaQkMP1Fn+WV6dQzmacYyJYieupxs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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