SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66313c7a4451584ea57641881d9df6ded6f6a77fd2bb069b7eef4d3fbba3949a' 
  AND token = 'OgGyU3Ro9ymjVb5zUIm/rhvRnLvg4zVPuxJIzcOot1w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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