SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '047c62a6d9b89722185997afb6ece9d6b8b998ad04d96acfddbfb20f34262095' 
  AND token = 'sggWukvvQxqBCEvp3HCy0fjFcwnqGSTLKCo64rwdGv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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