SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba61a503aaf1b8c8ed9861a24f0b941444a413a2f97e8b68780749cbd0f9ba46' 
  AND token = 'NRDVLidyEf+uiEmJw1tG8+snNDSAZSpWER1VSNDQlvM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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