SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1611c0768acdc6092f99c390b2bd0d2008e71fc039c5bac885ea8a6064896bf7' 
  AND token = 'CIbbDzfbh77EsAplxAYiFZvoEbMihLMSwDJEyOKOSmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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