SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ee29c6d4b7e95942fb519df13064baf5312b723910397bb5f6fdbc30defb505' 
  AND token = 'wERUCL18wF7IvnTFDYd9LLgae5jyUeGgD+Q5idzXw74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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