SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e790705765a7e8b50af0ef768c6b0c16bd7f7563abac4a74a5d95895eb18fe7f' 
  AND token = 'TqCWu/yVWO+o8pRabbQGGhT4Zpauo+k8AEWUmUdbTj8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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