SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fa5f955b5216ef91e7a26b20d72ee5cd654ef01132a88f4095fa05661571598' 
  AND token = 'UAWhqoGOJNodXqF0PsFrR8irr+7ALWYW3smZudMzCw4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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