SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d0cdc778610ef481cd259e1ed756edaf93aef5d40bf6b0f0132f79d3bc2419f' 
  AND token = 'nhI3a61yZyvaH4OAjf7UdOmSDQXeT9B/igAIivNrqAs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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