SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60c47887bf027e67f73cab3e90b9dd84fc3bf7da5337d0737ecb81795a555084' 
  AND token = 'PywljENIavdJWsOxdHBinygj/c3hPHkW+Ut4zhsdijk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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