Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd20be62aa82de0a21477476102c8b0b188f7f7dd7c2e4b55fd1ebb5f2bda72c5' 
  AND token = 'vxCKyrYeYvEKKtpo4OQ3nt807Qid3ALOKhZSsg4p3gs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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