SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5a25d4119bb68dede69b7a0a9483afa269e35527c11b0fca53c824d88753e4b' 
  AND token = 't2kf5JxXvyjJfuFf5qFLc4iEWJP2JTTi01cqV0TXysg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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