SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c6129f2a5ac68db7524d534b4459bce2ee03225b9883aa93f2929c8c43793db' 
  AND token = 'zEw2HTLZAVWGxUr9mGIgusNlISzoAfcIFvILvJ7dAV4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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