SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86c1dd54a7a13510eb3a8ba090cd372790330676638be41b225243f432f27082' 
  AND token = 'rurRE8FfroGnX4XEoAmsNEWKE5km+w8F1iJr1WqdXVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00105

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}