SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6379c230d9c3d4e3abcc9c8216e8585f291b4bb4b5bd5b2c4aff02a4b98a08ce' 
  AND token = 'VpCDMTZs0ecPQDsKx1cIeXsRwOBnIQyVfrK3YVAiwAM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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