SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c1c7e1780816b8ae722af5ffd41cc568c4eddbd644b8d5391d1687cd7ae932c2' 
  AND token = 'L/UkCkQkiMdRRn4h7KzxgO0Z6rV3VFBHUQq/VdWWZbw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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