SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49ea02732d2be1dbfae55c00c3c547299457812451f714286fedcc4ded3809b7' 
  AND token = 'wkjmUak+2IUrHZYX7/YFgoIQ9gPqwQh33KJou8+wW8o=' 
  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"
    }
  }
}