SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '35bf0e18d2e295fc3b370323b4d430ccce8ce2227f832c1454a0db4c3648d967' 
  AND token = 'DmWWAhNr09RqiJu6dU16U8vETuc3PxIvHp1ygOKWvgM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00069

JSON explain

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