Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b18befd643ade00b9db17443d488ee2d1eb6b1c9983c696c254ba3ef79575404' 
  AND token = 'GIIkIwl6ys85wJuhAGlchZknOx9Ymu5fpMKBtXoBuWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}