SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fad5b05effd3c38061fa598a74512186de2891f7bd8aeb87d2f215c40f467cc9' 
  AND token = '0ZsxPGMUdErIarEbGeWtLnJ7bmyyH0NIXrVpydGD2mc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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