SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '967bf71d84f397dc94a476b036412f589929a6ec3b243b0ac8cc6da25b9e1332' 
  AND token = 'iIwrMwlAm8BntwqmZAy3UdLTJ5MhU99GcXqw9Nuz8GY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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