SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07ebdcdd3d5bfcd366bac19e601e04b308c9934fc6ce292302d5b27a51c884e7' 
  AND token = 'l5eG3jQLM1lC0kmRxMaO5AKzRRdkrd7K5pjaR6y0mC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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