SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e3b444538d257f595eb178e987138edcb4c02baf63b8fb6b7895247457addf6' 
  AND token = 'oXMBLUscsH4KMaLlL+fnG9MtWjq8cnqCXGIf57KGcLU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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