SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe2f70fb1009843e64229a5a9c4cf0d772bdb4fa3f788a53d49a347019888d84' 
  AND token = 'wbEGAXNS8pdbwmE8QUidsYoTMQTPnwOjIjQ69Nal6+g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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