SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '811ad89b95d8f3a040fc3d2171dcb08588f6661e47a1c019c484009e6ab05693' 
  AND token = 'njZ2vnaIPtY/xqNlJbkhXMlk2PqnDYfoCbfRYYPmORU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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