SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1612bbe853ea9732de696c7bfbfefbb37fae1ac5eb2c946125cabc01505ad2f4' 
  AND token = 'gaYx36qKs30QYaEkejgSnTw/CexmiJKN86d3SPgtw1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00094

JSON explain

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