SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dc20166f49dbf4d771615970f47ebf089ce029aec8e818dd1c83f62071f54eb4' 
  AND token = 'sqG8nSXoY6DVwjiI7MehR8IGK/JqVAp4APn2ksWSA5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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