SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '897c410cebd5bf8f30d5daa2643db00f80aa402e0bcc73f0258a30573793e576' 
  AND token = 'Q3+SXn0JEKUacLgptk71brAurXKV/whlV0gr2ZhEgwg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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