SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36073059224710d87dc6cd4e6b1c6888048c92fed26dda271fa4a4ecb2a39f83' 
  AND token = 'gSFZMyWD+wmIwxWgUkCbQKRQyT+vUAJPQ7lue2W5RYs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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