SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9ac1e3dd7b99977d9dbb8790a08997f945471e68e4738f43fd00ca3332fea25' 
  AND token = 'O7+anNnJkEQzqZwoBmGkBvybZheozPuUl8gnroOSNjU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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