SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c5f432df4ab4eb7fe922d8319955abe0b52af1b1d89a01f3e10cf18652f7b30a' 
  AND token = 'vRUG61e6EikyiDee3DollkwQgj1zjXqttX0WXh4OdPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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