SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '048fc26ac59870ff95e53be27de6c661cf4cf867caef9cfc2ed221ffd0428b92' 
  AND token = 'jJdEUAzuMpjyAiGK+uaGe2TPipXGqFmJmhIRDBzmNSA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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