SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd1d3c78e4bc9bb6f559116a5d7247d8c3058bb74520b14a6a1e9bc95bbe2f322' 
  AND token = 'M9DFZ8rwgCYtcfupVNOy1bReaza9rZvLDiqcMlvOZAo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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