SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba5dcd15bbc37350276a07eda6b71ea40f6ef3f3ecccd2cff251c070567e464a' 
  AND token = 'bCFLM4Zc54TgPuV21kw9RzrIoYqCXCwiQY3j4J9K9ig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}