SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82d618fcdab871425bc44fff71bb375edc262ff47d7ffc3079d7171bd94a7c90' 
  AND token = 'xGFgRAYpRR6paclcpqXQbGP7tYXU4Y857YP9gVhWhaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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