SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59d93a2dfee4ff559035cbc2c496e11bc65cf7f677f61c1ce9605d0509ffc478' 
  AND token = 'VnAQq49oZT04HmpKAIqiiu/PDcyD4CEAzHsP9MSUXSc=' 
  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"
    }
  }
}