SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a65417e563111365bc857b688b0823f376faa1d51aed2214356ef2525a0331e9' 
  AND token = 'j8WwDCTN66I4GANV7FUug2lDNlcLNcbaZri5o3gaPvM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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