SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fddba5081d7d75917de3649d0d4941dcab7b3249b00579e30091e22e4b4b3ae0' 
  AND token = 'GV2WlhnrVkRsL6K7ykG+9fOCelkznknb63Lixv/xAV4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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