SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f4d5e9a3cdc697509409a75f63fa8a0230c896f05250ab1b40c68e587722070' 
  AND token = 'gfooMRuJqZsskRkLWTgGFIyu8WzaWQ/ipt32DUodB4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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