SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc7048ce006182951b722fda4a9c1a8a61a0799a0ef0d0753bd15136e4cadbba' 
  AND token = '2JkaiT8rtGueHDoFdQMYTkRdS4m8NvKWKC61eIo0fBA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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