SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7769e79a117c056ecf64bf9a1c54dd113f7d27f917e2603b2548335391557cd' 
  AND token = 'vticM/v1Ck9qT5y0xWWuTiggQlZR6e+jJY9uY+h63/o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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