SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52bd10fe891f3127a5b3c166b683e121f72b5bed583cf5e67d2c57f75fae01e6' 
  AND token = 'xxNWZiNz5tclyyTmABBOYB9gJltqH/tqq352MhdROTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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