SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6af39651a71ba74d532d9ce34ed54df6629b7368129a880461fe9efe5140763c' 
  AND token = 'TcevI9Uuu6sSVhtPFlojW3A++v64zs+onA0WZZiMkF4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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