SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dbf92e84461587cc8070e86922fee0e9da6fc510e73da5a7c6472a8793847faf' 
  AND token = 'ptfheVS4K5zJ6RtyfLsXfRzqYL+F72WtVH06DK9YwQ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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