SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa2c12a3dc34a4d16293b5ff63358c0490b1f5269d3d0ca8ac8b91d107971710' 
  AND token = 'WfJS2z/M4BIpQGJxJ26xnQLw1EN7Y/0LRCxDkjFhOyU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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