SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3dad6bb759c637b089bd524fda5e61703385f36cb176df896b50b08e361f333' 
  AND token = 'Bs/5OJ/bUYpOun6kZuxrGadLq3fvZjQFaZLImgUGCAE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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