SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30e89159670910091b6e2c437153f672cda5a3b07bb67922f984fc07a0d46aac' 
  AND token = 'ZrZLb5ByZsmpXI2IX/8VnPpRQvBFaGfB7NmtCxgfLYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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