SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3bc2bd337fb176f6357df68c7e3c0a342d9626ba5ddd5a0432c3e5c07a421abc' 
  AND token = 'NB/bFcLmClCz5EyTlZfmimcXuQFC+fmRtjz2YdgkwFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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