SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '560f8c7354197da78a060b98ba818594d6b58db9ea472cef5e83f39c4bdcddaf' 
  AND token = 'B6l1At308pKBuayJwOcQryi6kMqx7MpEnK10PapgFM0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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