SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28bc11124d0821915d8180ff5a1af32bbd9efbe98b9e0996e7842cf0218011aa' 
  AND token = 'SyD2Tk+yN9wvyAnIUIRPhldsHKRXNOF/kPMI7agY3jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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