SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e4df9140227e008dd6166426a7d255003515163fbfd346553c0b2d3d25e9f85' 
  AND token = 'LhwXToRJ7k4yccbIutXmgI1KPcaQKeKvB63e5OkYJfs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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