SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3828a89e43c5e3cacf5fdcbbac0f11e9d476f07dca8e5131fa363668a75639f' 
  AND token = 'mUcL8Iav98bzwT/yCAKm4/AIArJtM/xEqaq2BOchaV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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