SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1097c656ecec0519759c00d6e21aee598c638781bb31e2bf415fff94645d2d1d' 
  AND token = 'iTCOzycvr/neWnmfnWiQJUJT/x7Qh4l5SGifuFVoNXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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