SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c86cdaee0ea8c270d3c2592832dcbf6e15b7a553fa95ba0748694e2340acf13' 
  AND token = 'aLh7mNmWwwbT07yKJ8wmlsbNGthTkbgK3E60lIDluik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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