SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8189a1f9bd69b81ffde188102eaa8b3331c63d42a3ae0785d6244b7c8d4b5106' 
  AND token = '1jmEbvAwxBw0y80E70GlLfTjCj17k5YbRzPBNClUI3k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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