SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0682fa3f0102421702eb946622caf03841c9bdc2e98c1582ca2500c7af0d8485' 
  AND token = 'o+Kgpb0nZSk/VesXudSNaBYaWkvqTM1knhAeYTWhwzo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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