SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '83c1e3d2a71057acfb86f53d5dcd63f158a69b29229e52a4d83886ac6d7585c1' 
  AND token = 'CYUXtHhZbU67sjJTTzfuuU6XmQ8quL/yF7452oSk1VA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00072

JSON explain

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