SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4f237c3b2833be3cb1f662715ba2f5810941dd9e18e474a9da00489e787d21a3' 
  AND token = 'cuBnGso//Y+Ozqev1yAG8y4tKQPR50sRvn48IgZ0Evc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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