SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba57a9f749bd84b27962783accc08b72b5d2a3ddeb8bbe0a06411eacb57dd58f' 
  AND token = '49W15mOmXNhzkRHFClh3YBRkFt4VugtAYx/qm6YHJQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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