SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00d632552472ec550cd590dd1e2ad20e77391eb5788c5fdda39ce7e7751b1beb' 
  AND token = 'A9FwYn1kpKP/TpbCTsn8xP9YytAI2oLUgkQiCKvFAac=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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