SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f5d490ea35d2ae8df38a7363e9ffeb189fbe32568f1d259841c6eb30369c52c' 
  AND token = 'pDNg+E0IJYcp7NT8xRtLcz94p94sjZttRkhFShtFeP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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