SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2b48e55b58af4b8c66a13afd43bc1e99e4262950a8d7439560159bcefad0163a' 
  AND token = 'PoOMdfekLFRpJVrBz1wMrapgB+WFtWxBh5Ihd9TNkTs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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