SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd2c7ce8e07ad45aaa7c939eb12e06362ddc0f65a8e26079dbd7da34078d1cbb' 
  AND token = 'w/pfyZDpwNH9apwOtwG47B7JaOF7xVc6DW5qHkoHQPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}