SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '533a10f74500d918a55ed63c8374a4a65902ee7c59443c8633075b18776819fc' 
  AND token = '37JxjAIr5JCGmEP7/23cFAVghY2LMNNzREqgNfX8gQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00093

JSON explain

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