SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '073569096f623d89663c36a8998f5841f6191033336e43b3703dcc4f92ac61b7' 
  AND token = 'PzVcTB3WkRoSNaK7QRNSKtY6uE4Yg3EoO5Fy6epHcWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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