Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '668bf92af8d1e3bc9522ba4ffedcda8aa49ac3f984dc3b9928e1dc84d48094e0' 
  AND token = '0LETGj3ZN9ZnVqMcM4PaA02e+IDce3vlZmju93ZYvlk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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