SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0bd8bdfde12bed4b87b939dab088b304b66c55aecea3eb2f85fac0a9724f93e1' 
  AND token = 'I/j9wijfWIHBuy6K2IuCwVGjc9wNFydw8WqciuTbtO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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