SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '811a16ec2bd3776a34adbbb1bcc6f6543ff77570c544ca6e4b28ee4265f89f4f' 
  AND token = 'YaAjLErfqnmPVmjKYKCKmpJ3cksmEXCKcJodbz75oWo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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