SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2dc5136010a49b7fb7302bbd71db43a5593617127bdbf30fc487e22a2a1728c0' 
  AND token = 'X6NwO7kk9NhiAK33tGmQtdsNNeoGPjZckuRO0gIC/zE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}