SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19cd4d0eca660002c4d570371ec94293ac93bb30fefe9aeedfcad102b3d75811' 
  AND token = 'YeM29YCPVj7pFafrUZBKcU5ta3BSJbwQd/5E1LQ6nS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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