SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7957a6859d39b782d7b6e8bf50fcd1c1164ff2d2b03e8e133ab28351c79c1d64' 
  AND token = '7g4CtAQhWvA8rfdfsi/G7xvTbhuhPc7ztZJgS3wKOAw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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