SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e510e4631b072226a278533964d2107350d3059a28d210e7d7d2ac2b42aade1d' 
  AND token = 'yipL3qHsgpG9HVvh8YfEbaKPZflKtP3kakwceEuaYcM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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