SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43f9d23a00a9e101347955775642802ed373c40d16ca4826ca8baeb3fa27776a' 
  AND token = 'XUKYymAKiDPq1UEFDDXqqXH5PdROK7Rf8sLyPmj2Yys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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