SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '725bffd991bdf2c375ff9530ebdbaf6f0ceeb212c2eb81a6886ea8662f037cd4' 
  AND token = 'mZL0OynrXJiO3B1nfXho/hMi/6abz9Hv7H5GZnLt/48=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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