SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2df6006b4d7b2036fc44d8d7c2afacdda6864aac0679a550aa366d5f49037dc8' 
  AND token = 'C6Lo2IyChJ4DjEC3fE0bOj7DYW8njy9JYX9h4wk6UYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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