SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea166c00f89de16dff53d5192f4d7c0cbf2d468ec816c8596522864c0ed30b5e' 
  AND token = 'FvvoYcPK8/KTVHnw1kJe4QEZ5FXHf/bKbamB5BgzZ9k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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