SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a1d16ecf2ce19b0bd53bd73c2843d06bc3a6e8ec5df343956240c8b77f820eb' 
  AND token = 'bw6WDWOSXhybufrCmSk+ZI75Q+XODkZ+qrkjiqc6hQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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