SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c0fc5bda700d0c2f359ce3dbb6da20a5835334a6b7c1e3bc72898bc1f817f1f' 
  AND token = 'YXUE4D9aLPX8iAgRQD76baJGtJlbm/4ZqYQNsPNxcCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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