SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '977b4466f0584755d5dab9c4f3ff6ff5e700bab63725d7d0fbbaef03e62594bd' 
  AND token = 'HlkDBdYnV2oFIKUFXcSgCbrbGMui43ct8ZhH1M+yilk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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