Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8b24f6da08341381d4df3de75a4b8fdce7732bc48104b09d3f313448e42d14d' 
  AND token = 'b2B9xoe6uzgi8PVLGWnx8ShPvsWN9oU+jBwXYZ9nyZ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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