SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8091c5b8651d02858d3babeca79ba79dbb85aef44c8b1ced5472450c4f0d35cc' 
  AND token = 'RifXJaQQc5v620E4S3QyIIkNC5vuSWtRDI6OBldu/cw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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