SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a0935b5be579e604c75580a679caa4b201e2559ebe5390a825c269b211f527a' 
  AND token = 'AiByZdAcS/iw0gG068M9CNvVoD5q0KdEyCVJ/QTRbxc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}