SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03a114f31aae01b33a8e353f22aa2d37afeb6376706c93c9913621f67ba08d34' 
  AND token = 'TNTgKC6cUiHZeRSydBgwe+8C+TZy64mcHHuCh/tW6SM=' 
  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"
    }
  }
}