SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b85833236710adeb294c0ef6bf8ead143bcd38db3499036a18067a8c79b55d12' 
  AND token = 'B1umutuA+zjK2OTqxrKmf9BHf1Y9M71eKfA/GZGoNGI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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