SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b5ce4237f4ea5f4ff617e1acd68ebc36071417e09002616d4f8a43a635834050' 
  AND token = 'jHC6GA6WmUeL2YQDiPpvBv5r8cjL6lVm0nTKjnZxLlk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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