SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0bfa23d8b0d931add9c902b486be9f4eec6297bdbbeb37791c271c31e460b829' 
  AND token = 'pWU+ITs7V1GK6fQGrqHl9FBBvFTW5PfS/XMdrYJmWew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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