SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a0188e9ccc46a0d99b3a249325f0050087c592862c00dac7ab07756af1cc3ca' 
  AND token = 'UuJF0KpuySxVV2I2E/lyDWokmnsnkRXaKpfkzLIhAHA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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