SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '854bcce87143e8ea3e7d321c77d8aa247bc98f52ae552e6261cb6f57596bcfc8' 
  AND token = 'e0CmriiWplAqJTIu0o7wGAnFAASeQVjhkIwqrfp5C8I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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