SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8a565b6d9c68de7c555583bb6d8bd2035bcc1a794d2d98d7ead209e067f26eb' 
  AND token = 'TvUsM2W4604/vrT0EmW+sJDnmL8ava7Qnpcx6VA9AX4=' 
  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"
    }
  }
}