SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8b48b89493e2330bf43db6ed31b704965ddec4d9091092c5563262168ea02235' 
  AND token = 'tPkQA0ccEhzjMDDuqD+B31YQ9aH/q5LRl3wh0L9/FYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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