SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0233d93f717e429d95e5c51179c49311ea2a5a72d91ee99c1fd0a3b261fa5141' 
  AND token = 'pfjAJXIk+1Bv1JZ4Tb8CLeh7LrcE4J9dwpSnwHU4F5s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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