Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '6b3ed9427fc153cdc204b6425506f59c4eaad2ba4e8f17f483a6d17f5a8e2b84' 
  AND token = 'RTaM1h2W5ntqE5vGmqhAiMKsioSI8OuggD8CLowBVhE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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