SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '89d3539b32d49daa9bdca81bbb74b3fa515518eb833aae5f4ab69f5301289732' 
  AND token = 'RO2W9+xSRJhdmHOgQVIKITx9LVMZhdtc6E1QeqochsQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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