SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d4e3dd3b041abbbe9fb8aeb5cf4654ca7007beed8a160bc30d7948eec67597e' 
  AND token = 'ngnPRaLPDC7XZFP8qlrbr1QysbX6MHQmTfqkQzL2Yq0=' 
  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"
    }
  }
}