SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4bc5c88c3f779436a4aca8793610e5af115e6de623c171fd82ff698c43cb8518' 
  AND token = 'F94fcbnyCihAExcp0y55gKh12nbYAb6fAmYCFW52T5w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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