SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96966653eda8c939a7892148ce7615767131a2a1f3ec77238c9cdff31b89ea3c' 
  AND token = 'lEatJ7QKcFHlEYbinbHlo0ffM0QZz3hIJN7luJFj9yE=' 
  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"
    }
  }
}