SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27c8e84b016cd55d31bf37b24e9b85327ffb8a9e03897feeda6aa29e30cdd113' 
  AND token = 'J8eKoGhjElZqkW89LMxwMxIm7EVL01fEMfnqeLsgOlc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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