SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c42607b89e4e9bd75b9ed2963cd470ad353c76dea43f0aafe30f9afc1cce7fd' 
  AND token = '8ZNKCsq+3f9ybb2+04K//CJ9vLSjwWau0wMOuNPSeLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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