SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62fcbd45c61c10a0b07b8d8c98e13c93999b77b2a98cf624d25b85241a3d24db' 
  AND token = 'bKQ+ZuRH8natsjaxCsy2tietawPv+KFVBO1jYpqoqVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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