SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '400ff08630eac8f217491609d922eb7b6943c4fe9c1621f659f2c65be07e9f31' 
  AND token = 'lAQYkL5ZxllgIHNgeY6TZRPYQJu0/fbRqUupQVg+wQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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