SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4d397b3d620538371950cc1a39d462ef1e607264af930dd8c2b6b10fad8f7f2' 
  AND token = 'ppu/NSYNHWk0ntKPqzdHfBKL1QsLA/XKV/B6DOlZsjA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}