SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f72f04148902d41f9aa3b8232e32fba87bd7cd98f439598f73c3d827ccdc583' 
  AND token = '+EcnqtMUwH46kNDopJ0sX4MtlBrTprFw0VWhTZe31xw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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