SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72db9d3c461daf93ccfae75cbc7cbc7acb61d5a8e30bf912139aa9a94fb29f29' 
  AND token = 'WI4MqJtaokRHaBi3+mMcBGQUcT2eMd1es2i0CwGrFdo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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