SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '467e6650a305f20f4656311854c42be7419c93bdac367369f16b07b9d5326c83' 
  AND token = 'sudaJ8oHbx6QexSyRfJNIErnWvkCBT8fabif2PqihYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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